Chapter 43: Pediatric Surgery

Pediatric surgical patients are not merely small adults. The surgical care of children differs markedly from that of adults in many respects, including unique physiologic demands that vary according to age and development. The neonate’s physiologic development is closer to that of a fetus, while adolescents are similar to adults, and infants or children have problems unique to their chronologic and developmental age. Infants and children also suffer from congenital abnormalities and diseases not seen in adults, and their management requires an intimate understanding of the relevant embryology and pathogenesis.

Neonatal Intensive Care

The newborn infant with a surgically correctable lesion often has other disorders that threaten survival. The care of these babies—particularly the premature and small-for-gestational-age babies, has improved with the emergence of the intensive care nursery. Dramatic advances have been made in the technology of infant monitoring and respiratory support. Low-birth-weight infants can now receive ventilatory support from sophisticated infant respirators for prolonged periods in a precisely controlled microenvironment. Surfactant therapy and high-frequency ventilation has allowed a population of extremely premature infants to survive. Temperature is controlled by servoregulation, while pulse and blood pressure are continuously recorded. Ventilation is monitored by transcutaneous O₂ and Co₂ electrodes or by indwelling arterial catheters. The metabolic consequences of prematurity and intrauterine growth retardation are monitored by frequent measurement of glucose, calcium, electrolytes, and bilirubin in microliter quantities of blood. Nutritional requirements for growth and development can be provided by enteral or parenteral routes. This kind of specialized care of critically ill newborns requires trained personnel and specialized equipment. The care of such babies is best accomplished in designated regional centers capable of providing pediatric surgical and neonatal intensive care.

Classification

Newborn infants can be classified according to their level of maturation (weight) and development (gestational age). A normal full-term infant has a gestational age of 37-42 weeks and a body weight greater than 2500 g. The gestational age of the infant is calculated from the date of the last normal menstrual period. However, clinical assessment of gestational age by morphologic and neurologic examination of the small infant can be more accurate than calculation from the menstrual history.

Four signs may be useful in assessing gestational age. Infants less than 37 weeks’ gestational age have (1) fine fuzzy hair with thin, semitransparent skin, (2) ears that lack cartilaginous support, (3) a breast nodule less than 3 mm in diameter, and (4) few transverse creases on the balls of the feet anteriorly. In males, the testicles are incompletely descended and reside in the inguinal canal, and the scrotum is small with few rugae. In females, the labia minora are relatively enlarged and the labia majora are small.

Preterm infants are those born before 37 weeks’ gestation. Several physiologic abnormalities may coexist in preterm infants. Apneic and bradycardic episodes are common and may represent an immature central nervous system (CNS) or, conversely, may represent signs of physiologic instability, most notably with sepsis. The lungs and retinas of preterm infants are very susceptible to high oxygen levels. Retinopathy of prematurity from oxygen toxicity may lead to blindness. Relatively brief exposures to high oxygen concentrations, often coupled with barotrauma from the mechanical ventilator, may damage the lungs, resulting in bronchopulmonary dysplasia. Shunting across a patent ductus arteriosus is common and may lead to pulmonary hemorrhage and congestive heart failure. The preterm infant has a friable choroids plexus and is thus susceptible to intraventricular hemorrhage when stressed in the first week of life. The premature infant may be unable to tolerate oral feeding due to a weak suck reflex. Tube feeds or total parenteral nutrition may be required. Preterm infants have increased requirements for glucose, calcium, and sodium as well as a propensity for hypothermia, impaired bilirubin metabolism, polycythemia, and metabolic acidosis. These problems are accentuated in very low-birth-weight (VLBW) infants or “micropremies” (birth weight < 1000 g).

A small-for-gestational age (SGA) infant is one who is less than the 10th percentile in weight for their gestational age. An SGA infant is the product of a pregnancy complicated by any one of several placental, maternal, or fetal abnormalities. Although body weight is low, their body length and head circumference are age-appropriate. Compared with the premature infant of equivalent weight, the SGA infant is developmentally more mature and faces different physiologic problems. Intrauterine malnutrition results in reduced body fat and decreased glycogen stores. Their relatively large surface area and high metabolic rate predisposes them to hypothermia and hypoglycemia. SGA infants also have an increased risk of meconium aspiration syndrome. Polycythemia (which may lead to complications of hyperviscosity syndrome) is common and necessitates close monitoring of their hematocrit. Due to their relatively mature organ development and function (compared to preterm infants), retinopathy of prematurity, intraventricular hemorrhage, and hyaline membrane disease are uncommon.

Temperature Regulation

Infants and children are susceptible to heat loss because they have a relatively greater body surface area and a thinner subcutaneous fat layer compared with adults. Heat loss occurring by conduction, convection, evaporation, and radiation may be four times that of the adult and is further increased in the preterm infant. Infants are homeotherms and will expend metabolic energy to stay warm at the cost of other functions. Heat is generated not by shivering but by metabolizing brown fat reserves (nonshivering thermogenesis) in response to norepinephrine. This has practical consequences since brown fat may be rendered inactive by some medications (pressors and anesthetic agents) and may be depleted by poor nutrition. Exposure to cold environments increases metabolic work and caloric consumption. Due to limited energy reserves and thin skin, prolonged exposure may rapidly cause hypothermia. Resultant catecholamine secretion increases the metabolic rate (particularly in the myocardium) and produces vasoconstriction with impaired tissue perfusion and increased lactic acid production.

Thus, it is important to maintain the sick newborn in an optimal thermal environment. This is the ambient temperature in which a baby, at a minimal metabolic cost, can maintain a constant and normal body temperature by vasomotor control. To attain such an environment, the gradient between the skin surface and the environmental temperature must be less than 1.5°C. As the skin surface temperature averages 35.5°C, the optimal environmental temperature is 34°C (slightly higher for premature infants). The neonate’s environmental temperature is best controlled by placing the infant in an enclosed incubator. An open radiant warmer is used when the infant is sick and frequent access is necessary. Either the ambient temperature of the incubator can be monitored and maintained at thermoneutrality, or a servo system can be used. The latter regulates the incubator temperature according to the infant’s skin temperature. Heat loss may be further reduced by wrapping the head, extremities, and as much of the trunk as possible in wadding, plastic wrap, plastic sheets, or aluminum foil.

In the operating room, the temperature of the infant must be continuously recorded by placing a thermistor in the rectum or esophagus. Body heat may be conserved by a heating pad, circulated warm air around the child (bear-hugger), infrared lamp, and warm irrigation fluids. The operating room should be prewarmed and the temperature kept at 20-27°C. Wet sponges and drapes exaggerate evaporative heat losses. Plastic drapes contain body heat and keep the skin dry. One of the most effective means of regulating body temperature is to heat and humidify the inhalational anesthetic gases.

Ventilation

Assisted ventilation is often necessary because of underlying disease (eg, persistent fetal circulation and pulmonary hypertension), medications (eg, opioids, PGE₂), or physiologic changes imposed by a surgical procedure (eg, closure of an abdominal wall defect or diaphragmatic hernia). At birth, the baby should be warmed, dried, and stimulated. If the baby shows signs of respiratory distress, the pharynx should be aspirated of mucus, amniotic fluid, or meconium. Inadequate respiration should be assisted with positive pressure via mask and escalated to an endotracheal tube as necessary. There is an evolving role for a laryngeal mask airway (LMA) in newborns over 2.5 kg to establish ventilation, especially in cases of difficult airways due to congenital anomalies where intubation may not be possible. The diameter of an endotracheal tube (uncuffed) should approximate that of the 5th digit or the nares, usually between 2.5 and 4 mm. The full-term newborn usually requires a 3.5-mm tube. An orotracheal tube is preferred to a nasotracheal one to minimize trauma and subsequent infection in the nasal passages. The trachea from the glottis to the carina in the newborn is 7.5-cm long, and placement of the tube into the right or left bronchus must be avoided. For infants, optimal tube placement can be estimated as body weight (kg) + 6 as follows: 7 cm from the lips in a 1-kg infant; 8 cm in a 2-kg infant; and 9 cm in a 3-kg infant. Once placed, the endotracheal tube is firmly fixed in place and connected to an infant ventilator. A small air leak between the endotracheal tube and the airway is necessary to minimize laryngeal and tracheal trauma.

Most infant ventilators are time-cycled flow generators capable of delivering both continuous positive airway pressure (CPAP) and intermittent mandatory ventilation (IMV). IMV is a synthesis of simple mechanical ventilation and CPAP breathing that allows the baby to breathe independently between mandatory breaths provided by the ventilator while a continuous positive pressure is maintained on the airway. CPAP breathing helps keep the terminal airways open and is particularly useful when alveolar collapse develops, such as in hyaline membrane disease or with persistent atelectasis.

The gas mixture flowing into the system should be carefully controlled by an air-oxygen mixing device, and the inspired oxygen concentration should be regulated to avoid excessive oxygen delivery. A reasonable goal for arterial Po₂ is around 60-80 torr. The gas should be humidified by using a heated nebulizer as nonhumidified circuits can lead to insensible loses. When the arterial Po₂ exceeds 80 torr, the inspired oxygen concentration is gradually lowered toward room air; the end-expiratory pressure is incrementally lowered. When Pco₂ is less than approximately 45 torr, the IMV rate can be decreased as well. In this way, the baby is gradually weaned from oxygen and mechanical ventilation. Upon removal of the tube, nasal CPAP can be provided, and the inspired oxygen concentration can be increased if necessary.

In severe respiratory compromise (eg, congenital diaphragmatic hernia [CDH], meconium aspiration syndrome), more complex ventilatory strategies are needed. High-frequency ventilation (jet and oscillatory modes) utilizes low tidal volumes at high rates (up to 600 breaths/min) to minimize the deleterious effects of high airway pressure. Inhaled nitric oxide (iNO) can be administered via the ventilatory circuit and may help relax the small airways and pulmonary vasculature. There is a trend toward allowing higher Pco₂ levels (permissive hypercarbia) and lower Po₂ levels in order to lessen pulmonary trauma from pressure and oxygen. This has been termed “gentle ventilation.” If gentle ventilation, permissive hypercapnia, and the high-frequency modes of ventilation are ineffective, oxygenation and gas exchange can be accomplished using extracorporeal membrane oxygenation (ECMO). This temporary bypass unit oxygenates the blood through an external circuit as the lungs are left to mature or recover from the underlying disease process. The clinical need for ECMO has diminished with the increased widespread use of iNO, surfactant, high-frequency ventilation and the adoption of permissive hypercapnea as a ventilatory strategy.

Fluids & Electrolytes

Effective fluid and electrolyte management involves (1) calculating the fluid and electrolyte requirements for maintaining metabolic functions, (2) replacing losses (evaporative, third space, external), and (3) considering preexisting fluid deficits or excesses. Taking these factors into consideration, a tentative program is devised for fluid and electrolyte administration. The patient’s response is monitored, and the program is adjusted accordingly.

Monitoring fluid status and acid-base balance can be accomplished by both noninvasive and invasive means. Commonly used noninvasive devices include pulse oximetry, urine output, transcutaneous Co₂ monitoring, and sphygmomanometry. For critically ill infants, more invasive means are necessary to assess homeostasis. Blood gas analysis via heelstick (capillary), venous catheter, or arterial catheter is frequently employed. Polyvinyl catheters may be placed via an umbilical artery into the aorta, with the tip positioned at the level of T6-T9 or L3-L4 (confirmed radiographically). Indwelling arterial catheters can also be placed in the radial, femoral, or temporal arteries, either percutaneously or by incision. Central venous access may assist in cases where prolonged venous access is needed or parenteral nutrition is necessary or when blood is frequently sampled. It may be obtained via the umbilical vein; a percutaneously inserted central catheter (PICC) via the saphenous, cephalic, median basilic, or temporal veins; or using a Broviac catheter via the femoral, internal jugular, facial, or subclavian veins.

A. Calculating Maintenance Needs

In the newborn infant, the basic maintenance requirement of water is the volume required for growth and replacement of losses from the skin, lungs, and stool. Requirements during the first day of life are unique because of the greatly expanded extracellular fluid volume in the newborn baby, which decreases after 24 hours. For example, infants born with intestinal obstruction (eg, intestinal atresia) are initially not hypovolemic as a result of fluid adjustments across the placenta. Up to 10% of a newborn infant’s birth weight is lost in the first 3-7 days; the majority is water loss, with minor contributions from meconium and urine. During the first 24 hours of life, basic maintenance fluid should range from 60 to 80 mL/kg/d for term infants, and from 80 to 100 mL/kg/d for preterm infants. This requirement gradually increases to a minimum 80-100 mL/kg/d by 4 days of life in normal infants. For children and adolescents, the most commonly used method of calculating fluid requirements is based on body weight (Table 43–1). However, because of the many factors affecting maintenance requirements, there is no close or constant relationship between body weight and fluid and electrolyte needs.

B. Perioperative Fluid Management

In the surgical patient, fluid, serum electrolyte, and acid-base abnormalities are corrected before operation, when feasible. Intraoperative fluid requirements consist of the estimated maintenance requirement plus replacement of preexisting deficits (if uncorrected) plus replacement of intraoperative losses, including blood.

Postoperatively, losses from intestinal drainage and fistulas are directly measured and replaced with an appropriate electrolyte solution (Table 43–2). In neonates, it is wise to measure the electrolytes in the fluid to more accurately guide replacement, especially for proximal intestinal stomas or fistulas. Protein-rich losses (eg, chest tube drainage of a chylothorax) can be replaced with colloid such as an albumin solution or fresh frozen plasma (FFP). Internal losses into body cavities or tissues (third space losses) cannot be measured; adequate replacement of these losses depends on careful monitoring of the patient’s vital signs and urine output. Following an operation such as a laparotomy or thoracotomy, the fluid requirement may exceed 150 mL/kg/d for several days postoperatively. Isotonic fluids are better in the immediate postoperative period in patients over 6 months of age when significant third space losses are possible.

C. Electrolyte Considerations

Basic electrolyte and energy requirements are provided by sodium, 3-4 mEq/kg/d (up to 5 mEq/kg/d for preterm infants) in 5% or 10% dextrose, with the addition of potassium, 2-3 mEq/kg/d, once urine production has been established. Calcium gluconate (200-400 mg/kg/d) may be added, especially in preterm infants. Additional electrolytes such as bicarbonate and magnesium are added, as needed.

Many stressed newborn infants develop low blood levels of potassium, calcium, magnesium, and glucose. A deficiency of any one of these will produce such signs as vomiting, abdominal distention, poor feeding, apneic spells, cyanosis, lethargy, eye rolling, high-pitched cry, tremors, or convulsions. Convulsions and tetany due to hypocalcemia should be treated with intravenous 10% calcium solution given at a rate of 1 mL/min while the EKG is carefully monitored. Although hypocalcemia can be largely eliminated by adding calcium salts to intravenous solutions, caution is required since subcutaneous infiltration may produce severe vasoconstriction and skin necrosis. If there is no response to correction of a documented calcium deficiency, hypomagnesemia should be suspected and a serum magnesium level obtained.

Rapid determination of the blood glucose level can be done in the neonatal unit with blood glucose reagent strips. This may be correlated at intervals with serum glucose determinations, the frequency depending on the stability of the infant. Generally, intravenous fluids should contain a minimum of 10% dextrose, and if non–dextrose-containing solutions such as blood or plasma are being administered, close monitoring of the blood glucose level is essential. The treatment of hypoglycemia consists of giving 50% glucose, 1-2 mL/kg intravenously, followed by a continuous infusion of 10%-15% glucose solutions at a rate equivalent to that needed for maintenance water requirements.

Nutrition

Newborns require a relatively large caloric intake because of their high basal metabolic rate, caloric requirements for growth and development, energy needs to maintain body heat, and limited energy reserve. An infant requires calories at a rate of 100-130 kcal/kg/d and protein at a rate of 2-4 g/kg/d to achieve a normal weight gain of 10-15 g/kg/d (Table 43–3). Thirty percent to 40% of the total nonprotein calories should be provided as fat. These requirements decline with age but increase with surgery, sepsis, and trauma or burns. Caloric requirements are increased 10%-25% by surgery, more than 50% by infection, and 100% by burns.

A. Enteral Alimentation

The best means of providing calories and protein is through the gastrointestinal (GI) tract. If the GI tract is functional, standard infant formulas, blenderized meals, or prepared elemental diets can be given by mouth, through nasogastric or nasojejunal feeding tubes, or through gastrostomy or jejunostomy tubes placed surgically. Gastric feeding is preferable because it allows for normal digestive processes and hormonal responses, a greater tolerance for larger osmotic loads, and a lower incidence of dumping. The use of nasoduodenal or nasojejunal tubes is reserved for infants who cannot tolerate intragastric feeding (eg, delayed gastric emptying, gastroesophageal reflux [GER], depressed gag reflex).

The availability of nutritionally complete liquid diets of low viscosity allows continuous feeding through small-diameter catheters. Elemental diets made by mixing crystalline amino acids, oligosaccharides, and fats can be completely absorbed in the small intestine with little residue. Their use is limited because they cause diarrhea as a result of the high osmolality of full-strength formulas. This can be avoided by administering dilute solutions by continuous drip. Initially, the volume of dilute solution is gradually increased, and the concentration is then progressively increased in a stepwise fashion—ie, half strength, three-fourths strength, and full strength. Formulas that remain below 500 mOsm are best.

Small Silastic or polyethylene catheters such as those used for intravenous infusion can be passed through the nose or mouth into the stomach or jejunum. In more complex cases, a surgically placed gastrostomy or jejunostomy may be necessary for postoperative feeding. A variety of techniques and methods are employed in their construction. In the case of a gastrostomy, either a balloon catheter is used (ie, Foley) or a low-profile gastrostomy button is placed. Silastic is superior to other plastics because it does not become rigid when exposed to intestinal contents. Parenteral nutrition combined with enteral feeding is often necessary for infants with short bowel syndrome until intestinal adaptation occurs.

B. Parenteral Alimentation

The indications for parenteral alimentation include the following: (1) expected period of prolonged ileus (eg, following repair of gastroschisis or high jejunal atresia); (2) intestinal fistulas; (3) supplementation of oral feedings, as in intractable diarrhea, short bowel syndrome, or various malabsorption syndromes; (4) intrauterine growth retardation; (5) catabolic wasting states such as infections or tumors when gastric feedings are inadequate or not tolerated; (6) inflammatory bowel disease; (7) severe acute alimentary disorders (pancreatitis, necrotizing enterocolitis [NEC]); and (8) chylothorax.

Concentrated solutions (12.5% glucose or more) thrombose peripheral vessels. Placement of a central venous catheter (PICC or Broviac) into the superior or inferior vena cavae allows the large blood flow to dilute the solution immediately, allowing more concentrated sugar solutions (15%-30% glucose) to be administered. The catheter may be placed percutaneously through the subclavian or internal jugular vein or inserted by cut down into the external jugular, anterior facial, internal jugular, cephalic, brachial, or saphenous veins. For long-term use, Broviac (single lumen) or Hickman (double lumen) catheters, with Dacron cuffs positioned near the exit site of the skin, are preferred to minimize infection and to prevent accidental dislodgment.

Intravenous alimentation solutions containing an amino acid source (2%-5% crystalline amino acids or protein hydrolysate), glucose (10%-40%), electrolytes, vitamins, and trace minerals are used. The electrolyte composition of the protein solution should be known so that the desired composition of the final solution can be adjusted by appropriate additives according to the individual patient’s requirements. A standard solution suitable for infants and young children must contain calcium, magnesium, and phosphate to allow for growth. Trace minerals are also added to the basic solution (Table 43–4). These solutions should be infused at a constant rate with an infusion pump to avoid blood backing up the catheter and clotting and to prevent wide fluctuations of blood glucose and amino acid concentrations. If it is necessary to restrict the volume of infusion, more concentrated glucose solutions can be used to increase the caloric intake.

Complications of prolonged intravenous alimentation are numerous. The most frequent problem is catheter sepsis. Although catheter removal will quickly treat the problem, a trial of antibiotics effective against gram-positive and gram-negative pathogens is indicated. Catheter removal is indicated in the presence of worsening sepsis, three positive blood cultures, or documented yeast infection (with antifungal treatment after catheter removal). Clotting in the catheter may be controlled by adding 1 unit of heparin per milliliter of solution. Emphasis on a constant rate of infusion will minimize hyperglycemia or hypoglycemia. Analysis of serum electrolytes (including calcium and phosphate) may be necessary several times a week initially, but the interval is decreased to once a week when the patient is stable. Patients must be observed for hyperammonemia and for vitamin or trace mineral deficiency. Progressive hepatomegaly and jaundice of uncertain origin can occur after prolonged parenteral alimentation. This syndrome may subside when the parenteral solution is discontinued or when it is infused for a period of 12-16 hours and then the infusion is stopped for 8-12 hours (cycling) or when augmented with enteral feeding. Use of an ω-3 fatty acid based emulsion (Omegaven) has shown potential in moderating the effects of TPN cholestasis.

Blood Loss

Total blood, plasma, and red blood cell (RBC) volumes are higher during the first few postnatal hours than at any other time in an individual’s life. Several hours after birth, plasma shifts out of the circulation, and total blood and plasma volume decrease. The high RBC volume persists, decreasing slowly to reach adult levels by the seventh postnatal week. Age-related estimations of blood volume are summarized in Table 43–5.

Although not clinically significant, both the prothrombin time and the partial thromboplastin time may be slightly prolonged at birth due to relative deficiencies of clotting factors. Defects in the coagulating mechanism may occur in newborn infants as a result of vitamin K deficiency, thrombocytopenia, inherited disorders, and temporary hepatic insufficiency due to immaturity, asphyxia, or infection. It is standard to administer 1.0 mg of vitamin K intramuscularly to all newborns.

The blood lost during operation varies greatly according to the complexity of the operative procedure, the underlying disease, and the effectiveness of hemostasis. Mild blood loss, amounting to less than 10% of the blood volume, usually does not require transfusion. It is imperative to develop methods for closely monitoring the amount of blood lost during operations since significant blood loss is often underestimated in the newborn, especially the preterm infant. Dry sponges should be used and weighed shortly after use to minimize error from evaporation. The suction line, connected to a calibrated trap on the operating table, should be short to diminish the dead space of the tubing and to provide immediate data about accumulated blood loss. Visual observation may be used as a rough guide, but it tends to give a falsely low estimate of the loss.

Before operation, newborn infants should receive vitamin K, 1.0 mg intravenously or intramuscularly. If an extensive surgical procedure is anticipated, the patient’s blood should be typed and crossmatched in case transfusion is required. In infants with hematocrits greater than 50%, blood loss may be replaced by infusing lactated Ringer’s solution or FFP to compensate for losses of up to 25% of total blood volume. Greater blood losses should be replaced with packed RBCs. A transfusion of RBCs at a volume of 10 mL/kg should raise the hematocrit 3%-4%. The transfused blood should be prewarmed to body temperature by running it through coiled tubing immersed in water at 37°C. With excessive blood loss, clotting factors and platelets can be depleted rapidly, and FFP and platelets of identical blood type should be available. With massive transfusion a ratio of 1:1 of FFP to RBCs and 1:2 of platelets to RBCs has been shown to improve outcomes.

Perioperative Considerations

A. Gastrointestinal Decompression

The importance of gastric decompression in the surgical newborn cannot be overemphasized. The distended stomach carries the risk of aspiration and pneumonia and may also impair diaphragmatic excursion, resulting in respiratory distress. For example, oxygenation and ventilation in a neonate with CDH may become progressively impaired as the herniated intestine becomes distended with air and fluid. With gastroschisis, omphalocele, and diaphragmatic hernia, the ability to reduce the prolapsed intestine into the abdominal cavity is impaired by intestinal distention. It is critical to avoid bag-mask ventilation in these patients. A double-lumen (sump) tube, such as a 10F Replogle or Anderson tube, is preferred, utilizing low continuous suction. If a single-lumen tube is used, intermittent aspiration by syringe or machine is required. The correct position of the tube in the stomach is confirmed by carefully measuring the tube prior to insertion and by radiographs. Careful taping of the tube is essential to avoid displacement.

B. Preoperative Blood Sampling

Blood analyses should be restricted to those studies essential for diagnosis and management. The volume of blood drawn for laboratory tests should be documented as these small volumes cumulatively represent significant blood loss in a small infant. Generally, the only “routine” preoperative blood analyses for a neonate consist of a complete blood count and a blood specimen for type and crossmatch (in the case of major newborn surgery). Electrolytes in the first 12 hours of life simply reflect the mother’s electrolytes. Coagulation studies (eg, PT, PTT, ACT) are rarely indicated.

C. Preoperative NPO Guidelines

The following are general guidelines, but institutional practices vary considerably. The guiding principles in setting a standard include: risk of hypoglycemia associated with NPO status, tolerance or comfort level of the NPO child, and the desire to have an empty stomach upon induction of general anesthesia to mitigate aspiration risk.

1. Patients younger than 6 months

No solids, breast milk, or formula 4 hours prior to the procedure. Infants may have clear liquids (water, oral electrolyte mixtures, glucose water, or apple juice) until 2 hours prior to the procedure.

2. Patients from 6 months to 18 years

Nothing to eat or drink after midnight except clear liquids (water, apple juice, oral electrolyte mixtures, gelatin dessert, white grape juice), which can be continued until 2 hours prior to the procedure.

3. Patients older than 18 years

Nothing to eat or drink after midnight except clear liquids (water, apple juice, plain gelatin desserts) until 4-6 hours prior to the procedure.

D. Bowel Preparation Instructions

The bowel is mechanically cleansed for elective bowel resection. Opinion varies about whether a bowel preparation is needed for certain procedures as well as about what to use to accomplish it and whether to do it at home or in the hospital. An inpatient regimen begins the day prior to surgery and consists of polyethylene glycol-electrolyte solution (GoLYTELY), 25 mL/kg/h for 4 hours or until the effluent is clear. Metoclopramide (0.1 mg/dose IV) is given 1 hour before the GoLYTELY. Pedialyte can be given ad lib until the time to have nothing by mouth.

Outpatient preparations are reserved for patients over 1 year of age. Clear liquids are given the day before surgery. Bisacodyl (Dulcolax) suppositories and 8-oz lukewarm tap water enemas can be given the morning and in the evening the day before surgery. For children over 5 years of age, magnesium citrate is added (1 oz per year of age up to a maximum of 8 oz) and given orally in the morning and evening the day before surgery, along with 16-oz tap water enemas.

DERMOID CYSTS

Dermoid cysts are congenital inclusions of skin and skin appendages commonly found on the scalp and eyebrows and in the midline of the nose, neck, and upper chest. They present as painless swellings that may be completely mobile or fixed to the skin and deeper structures. Dermoid cysts of the eyebrows and scalp may produce a depression in the underlying bone that appears as a smooth, punched-out defect on radiographs of the outer table of the skull. They do not extend intracranially. In contrast, cysts of the face and scalp that are located in the midline may represent an alternative diagnosis of encephalocele and would be handled much differently so it is imperative to obtain an MRI or CT scan preoperatively. Dermoid cysts of the midline neck may be confused with thyroglossal duct cysts. However, dermoids do not move with swallowing or protrusion of the tongue since they are not deep to the strap muscles, unlike thyroglossal cysts. All dermoids contain a cheesy material that is produced by desquamation of the cells of the epithelial lining. Care should be taken when planning the operative approach to facial dermoids to avoid either incomplete excision or unnecessary surgical scarring in cosmetically sensitive areas. Dermoids should be excised intact, since incomplete removal will result in recurrence. Those lesions arising near the eyebrows should be excised through an incision adjacent to the hairline. The eyebrows should not be shaved nor should the incision go through any eyebrow follicles since a permanent glabrous area will develop. Recently, tunneled endoscopic approaches originating from behind the hairline have been used successfully to avoid facial scarring.

BRANCHIOGENIC ANOMALIES

During the first month of fetal life, the primitive neck develops four external clefts and four pharyngeal pouches that are separated by a membrane. Between the clefts and pouches are branchial arches. The dorsal portion of the first cleft becomes the external auditory canal; the other clefts are obliterated. The pharyngeal pouches persist as adult organs. The first pouch becomes the auditory tube, the middle ear cavity, and the mastoid air cells. The second pouch incompletely regresses and becomes the palatine tonsil and the supratonsillar fossa. The third pouch forms the inferior parathyroid glands and thymus; the fourth forms the superior parathyroid glands. Branchial anomalies are remnants of this fetal branchial apparatus.

A tract of branchial origin may form a complete fistula, or one end may be obliterated to form an external or internal sinus, or both ends may resorb, leaving an aggregate of cells forming a cyst (Figure 43–1). Fistulas that arise above the hyoid bone and communicate with the external auditory canal represent persistence of the first branchial cleft. These tracts are always lined by squamous epithelium. Cysts and sinuses of second or third branchial origin are lined by squamous, cuboidal, or ciliated columnar epithelium. Fistulas that communicate between the anterior border of the sternocleidomastoid muscle and the tonsillar fossa are of second branchial origin, and those that extend into the piriform sinus are derived from the third branchial pouch. Cysts developing from branchial structures usually appear later in childhood as opposed to sinuses and fistulas. Branchiogenic anomalies occur with equal frequency on each side of the neck, and 15% are bilateral. Second branchial cleft abnormalities are most common, occurring six times more frequently than first cleft anomalies.

Clinical Findings

A sinus or fistulous opening along the anterior border of the sternocleidomastoid muscle may be noted at birth and usually discharges a mucoid or purulent material. The patient may complain of a foul-tasting discharge in the mouth upon massaging the tract, but the internal orifice is rarely recognized. Some may present with an acute infection. The cysts are characteristically found anterior and deep to the upper third of the sternocleidomastoid muscle, or they may be located within the parotid gland or pharyngeal wall, over the manubrium, or in the mediastinum. Sinuses and cysts are prone to become repeatedly infected, producing cellulitis and abscess formation. Incomplete branchial sinuses appear as a dimple that contain cartilage and do not drain or communicate with the deep structures of the neck.

Differential Diagnosis

Granulomatous lymphadenitis due to mycobacterial infections may produce cystic lymph nodes and draining sinuses, but these are usually distinguishable by the chronic inflammatory reaction that precedes the purulent discharge. Suppurative lymphadenitis, most commonly due to Staphylococcus aureus, may resemble an infected branchial remnant. However, treatment and complete healing of the lymphadenitis is curative, whereas an identifiable branchial remnant will persist after the infection resolves. Hemangiomas and lymphatic malformations (LM) are soft, spongy tumor masses that might be confused with branchial cysts, but the latter have a firmer consistency. LM may transilluminate, while branchial cysts do not. Carotid body tumors are quite firm, are located at the carotid bifurcation, and occur in older patients. Lymphomas produce firm masses in the area where branchial remnants occur, but multiple matted nodes rather than a solitary cystic tumor distinguish these lesions. Mucoid material may be expressed from the openings of branchial sinuses or fistulas, and a firm cord-like tract may be palpable along its course.

Treatment

Nearly all branchial abnormalities should be excised early in life since repeated infection is common, making resection more difficult. Asymptomatic, small cartilaginous remnants may be watched, but they are usually removed for cosmetic reasons as well as the smaller risk of infection, compared to the true cyst/fistula. Infected sinuses and cysts require initial incision and drainage. Excision of these tracts is staged and usually performed approximately 6 weeks later, when the acute inflammatory reaction has subsided. Every effort should be made to excise the entire cyst wall or fistula tract (including the skin punctum, if present) since recurrence and infection are common with incomplete removal. Excision should be undertaken cautiously, as the tracts may lie adjacent to the facial, hypoglossal, and glossopharyngeal nerves as well as the carotid artery and internal jugular vein.

PREAURICULAR LESIONS

Preauricular sinuses, cysts, and cartilaginous rests arise from anomalous development of the auricle and are unrelated to branchial anomalies. The sinuses are often short and end blindly. They can be cosmetically unappealing and often become infected. Superficial skin tags and cartilaginous rests are easily excised without risk to other structures. Preauricular sinus tracts, however, may be very deceptive in their extent, and one should be prepared to proceed with extensive dissection that risks damage to branches of the facial nerve.

LYMPHATIC MALFORMATION (Cystic Hygroma, Lymphangioma)

LMs are benign multilobular, multinodular cystic masses lined by lymph channel endothelial cells. They result from maldevelopment and obstruction of the lymphatic system. Since they are not proliferative lesions, they should be distinguished from hemangiomas; hence the favored term of lymphatic malformation is currently favored over the more frequently encountered misnomer lymphangioma. Cystic hygroma is another misnomer frequently encountered for cervical lymphatic malformation. Eventually, sequestrations of lymphatic tissue that do not communicate with the normal lymphatic system develop. Fifty percent to 65% appear at birth and 90% by the second year of life. They are located most commonly in the posterior triangle of the neck (75%) (Figure 43–2) and axilla (20%), with the remainder located in the mediastinum, retroperitoneum, pelvis, and groin.

Clinical Findings

Cervical lymphatic malformations may communicate beneath the clavicle with an axillary hygroma, mediastinal hygroma, or, rarely, both. The majority may be asymptomatic; however, the occult LM usually presents following an upper aerodigestive tract infection as a result of increased or infected lymph flow, or following hemorrhage into the LM from a web of adherent microvasculature. Occasionally, very large lesions occur with involvement of the floor of the mouth, these can cause in utero hydrops or asphyxiation at birth when associated with airway compromise. There is a recognized association between cervical LM and Turner syndrome. These lesions grow along fascial planes and around neurovascular structures; they are infiltrative but not invasive. Large lesions may be recognized prenatally using ultrasound or MRI examination.

Treatment

There are two modes of treatment, sclerotherapy or excision, the choice of which is based on imaging studies (CT, MRI). Intralesional injection of a sclerosing agent is most effective for unilocular or macrocystic lesions. Examples of agents that have been used are OK-432 (a lyophilized mixture of Streptococcus pyogenes and penicillin G potassium), bleomycin, and doxycycline. Excision is carried out with bipolar cautery to ensure a hemostatic dissection and decrease the incidence of lymph leak and nerve injury. Nevertheless, postoperative lymph leak is common and is treated by closed suction drainage for days to weeks. Intraoperative cyst rupture increases the difficulty of the dissection since the thin-walled cyst is difficult to identify and the margins are obscured. The persistence rate following surgery can be as high as 50% since incomplete excision is the rule rather than the exception in order to avoid potential injury to adjacent neurovascular bundles. Given their infiltrative nature, persistence or symptomatic recurrence following surgical excision and unavoidable surgical scarring, the trend has been increasingly toward sclerotherapy for superficial accessible macrocystic LMs.

THYROGLOSSAL DUCT REMNANT

During the fourth week of gestation, the thyroid gland develops from an evagination in the floor of the primitive pharynx located between the first pair of pharyngeal pouches. If the anlage of the thyroid does not descend normally, the gland may form at the base of the tongue or remain as a mass anywhere in the midline of the neck along its truncated path of descent. If the thyroglossal duct persists, the epithelial tract forms a cyst that usually communicates with the foramen cecum of the tongue. The thyroglossal duct descends through the second branchial arch anlage, which becomes the hyoid bone, prior to its fusion in the midline. Because of this, the tract of a persistent thyroglossal duct often extends through the hyoid bone (Figure 43–3).

Clinical Findings

The most common physical finding is a rounded cystic mass of varying size in the midline of the neck just below the hyoid bone. The acute inflammatory reaction of an infection may herald the presence of a cyst. The fluid in the cyst is usually under pressure and may give the impression of being a solid tumor. Cysts and aberrant midline thyroid glands move up and down with swallowing and with protrusion of the tongue since they are deep to the cervical strap muscles. In contrast, lingual thyroid tissue is a rare clinical entity and may produce dysphagia, dysphonia, dyspnea, hemorrhage, or pain.

Differential Diagnosis

Lymph nodes, dermoid cysts, and enlarged Delphian nodes containing tumor metastases may be confused with thyroglossal remnants in the midline of the neck. Dermoid cysts do not move with swallowing. Lingual thyroids may be confused with a hypertrophied lingual tonsil or with a ranula, fibroma, angioma, sarcoma, or carcinoma of the tongue. These lesions and thyroglossal cysts may be distinguished from aberrantly located thyroid glands by needle aspiration or by radioiodine scintiscan.

Complications

Thyroglossal cysts are prone to infection, and spontaneous drainage or incision and drainage of an abscess will often result in a chronically draining fistula. Excision of an ectopic thyroid may remove all thyroid tissue, producing hypothyroidism. There is a malignant potential of the dysgenetic thyroid tissue located in a thyroglossal duct cyst; carcinoma develops more frequently in ectopic thyroid tissue than in normal thyroid glands.

Treatment

Complete excision is indicated because of the risk of infection and the possibility of the development of papillary carcinoma later in life. Acute infection in thyroglossal tracts should be treated with antibiotics. Abscesses should be incised and drained. After complete subsidence of the inflammatory reaction (approximately 6 weeks), a thyroglossal cyst and its epithelial tract should be excised. The mid portion of the hyoid bone should be removed en bloc with the thyroglossal tract to the base of the tongue (Sistrunk procedure). Recurrences occur when the hyoid is not removed and when the cyst was previously infected or drained.

TORTICOLLIS

Torticollis presents with a hard, nontender, fibrotic mass within the sternocleidomastoid muscle. It may be present at birth but is usually not noticed until the second to sixth weeks of life. The mass appears with equal frequency in both sexes and on each side of the neck. Rarely, there is more than one mass in the muscle or both sternocleidomastoid muscles are involved. A history of breech delivery is present in 20%-30% of these children.

Clinical Findings

Torticollis is manifested when the sternocleidomastoid muscle is shortened and the mastoid process on the involved side is pulled down toward the clavicle and manubrium. As a result, the head is abducted to the ipsilateral side and rotated to the contralateral side (toward the opposite shoulder). The shoulder on the affected side is raised, and there may be cervical and thoracic scoliosis. Passive rotation of the head to the side of the involved muscle will be resisted and limited to varying degrees, and the muscle will appear as a protuberant band. Because of persistent pressure when the patient is recumbent, the ipsilateral face and contralateral occiput will be flattened. Facial hemihypoplasia and plagiocephaly (flattening of the ipsilateral posterior skull) occurs in untreated cases, usually within 6 months.

Treatment

Surgery is rarely necessary for this disorder. Torticollis is treated with active range of motion exercises. The child’s shoulders are held flat to a table and the head is tilted and rotated in a full range of motion. This procedure should be performed at least four times a day, usually for 2-3 months. The firm “tumor” often disappears well before the torticollis is cured. If the muscle continues to become progressively shortened, with facial and occipital skull deformity, both heads of the sternocleidomastoid muscle should be divided through a small transverse incision just above the clavicle. This procedure does not reverse the bony changes that have already developed but prevents progression of the process. Recently, endoscopic approaches have been described in order to avoid unsightly surgical scarring in the head and neck region.

SUPPURATIVE LYMPHADENITIS

Infections in the upper respiratory passages, scalp, ear, or neck produce varying degrees of secondary lymphadenitis. Most of the causative organisms are streptococcal or staphylococcal species. In infants and young children, the clinical course of the suppurative lymphadenitis may greatly overshadow a seemingly insignificant or inapparent primary infection. Scalp or ear infections produce preauricular or postauricular and suboccipital lymph node involvement; submental, oral, tonsillar, and pharyngeal infections affect the submandibular and deep jugular nodes.

Clinical Findings

With significant lymphadenitis, the regional lymph nodes become greatly enlarged and produce local pain and tenderness. Enlargement of cervical nodes is most common, followed by occipital and submandibular nodes. Fever is high initially and then becomes intermittent and may persist for days or weeks. The regional nodes may remain enlarged and firm for prolonged periods, or they may suppurate and produce surrounding cellulitis and edema. Subsequently, the nodes may involute or a fluctuant abscess may form, resulting in redness and thinning of the overlying skin. Infected, matted nodes may become so hard as to be indistinguishable (on palpation) from a solid mass.

Differential Diagnosis

A smoldering lymphadenitis that neither resolves nor forms an abscess can be confused with granulomatous lymphadenitis, lymphoma, or metastatic tumor. Excisional biopsy is required to differentiate these lesions. After several weeks, there will usually be a reduction in the size and firmness of suppurative adenitis, especially after antibiotic treatment has been started. Recently, methicillin-resistant S. aureus (MRSA) is being encountered at near epidemic levels as a causative agent of suppurative lymphadenitis in the ambulatory setting. A high suspicion of an MRSA infection should be entertained in all children presenting with either a first episode or more certainly in recalcitrant and recurrent cases.

Treatment

In the acute phase, the patient should be treated with oral or intravenous antistaphylococcal antibiotics. In the subacute or chronic phase, the presence of pus in the node may be confirmed by needle aspiration of the mass. When an abscess is present, it should be incised and drained under general anesthesia. In those cases of MRSA infection, a prolonged course of either vancomycin or linezolid may be required for complete eradication even after drainage.

GRANULOMATOUS LYMPHADENITIS

Although typical tuberculous cervical adenitis is very rare in the United States, atypical mycobacteria (eg, Mycobacterium avium-intracellulare) is encountered and may present as a nonsuppurative area (usually cervical, axillary, or inguinal) of matted nodes with tenderness and a draining sinus. Granulomatous lymphadenitis and caseation may occur in the regional nodes draining the inoculation site of BCG. Cat-scratch disease causes a caseating lymphadenitis in regional lymph nodes (eg, epitrochlear and axillary nodes enlarge after an upper extremity cat scratch).

Clinical Findings

Children under age 6 years are most frequently affected. The initial manifestation is a painless, progressive enlargement of the lymph nodes in the deep cervical chain and the parotid, suboccipital, submandibular, and supraclavicular nodes. The duration of lymphadenopathy is usually 1-3 months or longer. The nodes may be large and mobile or, with progressive disease, may become matted, fixed, and finally caseate to form an abscess. Incision or spontaneous overlying skin breakdown will result in a chronically draining sinus. In tuberculosis, both sides of the neck or multiple groups of nodes are infected, and the chest radiograph indicates pulmonary involvement. In atypical mycobacterial lymphadenitis, pulmonary disease is rare and the cervical adenitis is unilateral. The tuberculin skin test is weakly positive in over 80% of patients with atypical mycobacterial infection. Skin test antigens from the various strains of atypical mycobacteria are available. A positive skin test helps differentiate granulomatous adenitis from malignant lymphadenopathy. A fluctuant node can be confused with a branchial cleft remnant or a thyroglossal duct cyst.

Cat-scratch disease is usually acquired by a bite or scratch from a kitten. It is caused by a pleomorphic gram-negative bacillus (Bartonella henselae) that is detected in tissues by a silver stain or via serologic testing. It is an acute illness characterized by fever, malaise, possible musculoskeletal manifestations and occasionally a pustular lesion at the site of the scratch. Tender lymph node enlargement usually develops. Two to 4 weeks later, regional lymphadenitis persists, producing painful, fixed suppurative nodes that may develop into a chronically draining sinus.

Treatment

Atypical tuberculous lymphadenitis may be treated with rifampin (10 mg/kg/d), though definitive treatment usually requires nodal excision. Trimethoprim-sulfamethoxazole may shorten the course of cat-scratch disease and prevent suppuration. When antibiotics are ineffective, the procedure of choice is excision of involved nodes before caseation occurs. Once the nodes become fluctuant or a draining sinus forms, a wedge of involved skin should be excised and the underlying necrotic nodes should be curetted out (rather than excised), taking care not to injure neighboring nerves. The wound edges and skin should be closed primarily. The value of continuing chemotherapy is influenced by sensitivity tests on the cultured material. Excision and primary closure usually result in excellent healing with good cosmetic results.

STERNAL CLEFT

Failure of fusion of the two sternal bars during embryonic development produces congenital sternal cleft, which may involve the upper, lower, or entire sternum. In its severe form, this defect is usually associated with protrusion of the pericardium and heart (ectopia cordis) and congenital heart lesions. Defects may be associated with extracardiac anomalies, including cleft lip, cleft palate, hydrocephalus, and other CNS disorders, or may be one component of the pentalogy of Cantrell. Operative correction is performed in the neonatal period since the chest wall is so pliable; it consists of simple suture approximation of the two sternal halves. More complex defects associated with ectopia cordis are often incompatible with life.

PECTUS EXCAVATUM

This depression deformity is the most common congenital chest wall abnormality, occurring in one in 300 live births, with a 3:1 male predominance. It is associated with other musculoskeletal disorders (Marfan syndrome, Poland syndrome, scoliosis, clubfoot, syndactyly), and 2% have congenital heart disease. There is a familial form. It results from the unbalanced posterior growth of costal cartilages that are often fused, bizarrely deformed, or rotated. The body of the sternum secondarily exhibits a prominent posterior curvature, usually involving its lower half (Figure 43–4). Commonly, the xiphoid is the deepest portion of the depression. The third, fourth, and fifth costal cartilages are usually affected, though the second to eighth costal cartilages may be involved. The severity of the defect varies greatly from a mild, insignificant depression to an extreme where the xiphoid bone is adjacent to the vertebrae. The depression may be symmetrical or asymmetrical with varying degrees of sternal rotation.

Clinical Findings

These patients are typically round shouldered, with stooped posture, relative abdominal prominence, flared costal margins, and an asthenic appearance. They may be withdrawn and refuse to participate in sports activities, particularly if their deformity might be exposed. Few patients complain of easy fatigability or inability to compete in exertional activities. Cardiopulmonary function studies rarely demonstrate impairments; this is predominantly a cosmetic deformity with potentially severe psychosocial sequelae.

Treatment & Prognosis

There is no standard age for repair. Undeniably, it is an easier operation in younger children compared to adolescents. Drawbacks of an early operation include a higher risk of recurrence during the adolescent growth spurt and the inability of a young child to comprehend and assent to a predominantly cosmetic operation. Traditionally, an open repair (Ravitch technique) was performed in which the abnormal cartilages were resected and the sternum was fractured and fixed in a corrected position. Recently, the Ravitch technique has been supplanted by the less invasive Nuss procedure in which a preformed sternal strut is passed, either blindly or with thoracoscopic assistance, under the chest wall muscles, into each hemithorax, and across the mediastinum under the sternum via two small incisions in the midaxillary line. The curved bar is passed upside down and “flipped” into position under the sternum, effectively lifting the sternum and chest wall into a corrected position. The bar is left in place for 2 years, and the patient can resume activity in 3 months. The long-term good to excellent results of the Nuss procedure are better than 95%. The latest evolution in less invasive techniques involves placement of opposing magnetic field implants to draw the chest deformity forward and effect remodeling. In general, there is no cardiopulmonary benefit after chest wall repair except in rare instances when the deformity is excessive. Otherwise, the repair is performed solely to improve appearance. However, the psychosocial benefits of repair of this often embarrassing deformity cannot be minimized.

PECTUS CARINATUM

This is a protrusion deformity, also referred to as pigeon breast or chicken chest. It is approximately ten times less frequent than pectus excavatum. It results from the overgrowth of costal cartilages, with forward buckling and secondary deformation of the sternum (Figure 43–5). Atypical and asymmetric forms with rotation are common. There is a familial form. It is associated with Marfan disease, neurofibromatosis, Poland syndrome, and Morquio disease. Unlike pectus excavatum, the deformity is typically mild or nearly imperceptible in early childhood and becomes increasingly prominent during the rapid growth in early puberty.

Treatment & Prognosis

As with pectus excavatum, there is no cardiorespiratory compromise with this deformity, and repair is performed solely to achieve an improved cosmetic appearance. Mild deformities should be left alone and the patient followed to observe for progression. Moderate to severe defects should be repaired, particularly when the patient indicates a desire for improvement. The deformed cartilages are resected, leaving the costochondral membranes (perichondrium) intact. Sternal fracture is usually not necessary. To ensure that the costal cartilages grow back on a straighter line, “reefing” sutures are placed in the perichondrium to shorten them. The costal cartilages regenerate within 6 weeks. A thorough procedure will provide an excellent cosmetic result in nearly all cases. Recurrences are rare. An alternative approach to operative repair is chest bracing via an orthotic vest that needs to fitted and worn by the affected child for several hours daily over several years. This procedure may eventually replace the operative approach, particularly for those patients who are motivated to wear the brace for a majority of each day (about 16 hours).

Certain aspects of respiration unique to the infant must be appreciated. Except during periods of crying, the newborn baby is an obligate nasal breather. The ability to breathe through the mouth may take weeks or months to acquire. Inspiration is accomplished chiefly by diaphragmatic excursion; the intercostal and accessory muscles contribute little to ventilation. Impaired inspiration results in retraction of the sternum, costal margin, and neck fossae; the resulting paradoxical motion may contribute to respiratory insufficiency. The airway is small and flaccid, so that it is readily occluded by mucus or edema, and it collapses readily under slight pressure. Dyspneic infants swallow large volumes of air, and the distended stomach and bowel may further impair diaphragmatic excursion.

Classification

A. Upper Airway Disorders

1. Micrognathia—Pierre Robin syndrome

2. Macroglossia—Muscular hypertrophy, hypothyroidism, lymphatic malformation, Beckwith-Wiedemann syndrome

3. Anomalous nasopharyngeal passage—Choanal atresia, Treacher-Collins syndrome, Apert syndrome, and Crouzon syndrome

4. Tumors, cysts, or enlarged thyroid remnants in the pharynx or neck

5. Laryngeal or tracheal stenosis, webs, cysts, tumors, or vocal cord paralysis

6. Epiglottitis

7. Tracheomalacia

8. Tracheal stenosis with or without complete tracheal rings

B. Intrathoracic Airway Disorders

1. Atelectasis

2. Pneumothorax and pneumomediastinum

3. Pleural effusion or chylothorax

4. Pulmonary cysts, sequestration, and tumors

5. Congenital lobar emphysema

6. Diaphragmatic hernia or eventration

7. Esophageal atresia with or without tracheoesophageal fistula

8. Anomalies of the great vessels (eg, double aortic arch, aberrant left subclavian artery, anomalous origin of left pulmonary artery)

9. Mediastinal tumors and cysts (foregut duplications, thymomas, substernal goiter, lymphoma)

PIERRE ROBIN SYNDROME

Pierre Robin syndrome is a congenital defect characterized by micrognathia and glossoptosis, often associated with cleft palate. The small lower jaw and strong sucking action of the infant allow the tongue to be sucked back and occlude the laryngeal airway and may be life threatening.

Infants with mild cases should be kept in the prone position during care and feeding. A nasogastric or gastrostomy tube may be necessary for feeding. Nasohypopharyngeal intubation is effective in preventing occlusion of the larynx. If conservative measures fail, prompt attention to maintaining an open airway by tracheostomy is indicated. Surgical treatment involves tongue placation in which the tongue is sutured forward to the lower jaw, but this frequently breaks down. In time, the lower jaw develops normally. These infants eventually learn how to keep the tongue from occluding the airway.

CHOANAL ATRESIA

Complete obstruction at the posterior nares from choanal atresia may be unilateral and relatively asymptomatic. It may be membranous (10%) or bony (90%). When it is bilateral, severe respiratory distress is manifested at birth by marked chest wall retraction on inspiration and a normal cry.

There is arching of the head and neck in an effort to breathe, and the baby is unable to eat. The diagnosis is confirmed by the inability to pass a tube through the nares to the pharynx. With the baby in a supine position, radiopaque material may be instilled into the nares and lateral x-rays of the head taken to outline the obstruction. A CT scan of the nasopharynx will define bony occlusion.

Emergency treatment consists of maintaining an oral airway by placing a nipple, with the tip cut off, in the mouth. The membranous or bony occlusion may then be perforated by direct transpalatal excision, or it may be punctured and enlarged with a Hegar dilator. The newly created opening must be stented with plastic tubing for 5 weeks to prevent stricture.

CONGENITAL TRACHEAL STENOSIS & MALACIA

There are three main types of congenital tracheal stenosis: generalized hypoplasia; funnel-like narrowing, usually tapering to a tight stenosis just above the carina; and segmental stenosis of various lengths that can occur at any level. Tracheomalacia is a functional obstruction in a “soft” trachea that collapses with inspiration. It is often secondary to external compression by vascular anomalies or tumors or from a chronically dilated upper esophageal pouch in those with esophageal atresia.

Diagnosis

The diagnostic approach to an infant with respiratory distress and possible distal tracheal obstruction must be carefully integrated with plans for management of the airway, since the compromised infant airway is easily occluded by edema or secretions. This is especially true in distal tracheal lesions, where an endotracheal or tracheostomy tube may not relieve the distal obstruction. The diagnostic value of every procedure must be weighed against the threat of precipitating airway obstruction. Tracheal lesions can be visualized using esophagography, angiography, or CT/MRI scans. Dynamic lesions such as tracheomalacia and vascular compression syndromes are best defined by videotape fluoroscopy or cineradiography with barium in the esophagus. Angiography may be necessary. Flow-volume curves can define the level of obstruction (intrathoracic vs extrathoracic) and the type of obstruction (stenosis vs malacia).

Although bronchoscopy often provides the best delineation of tracheobronchial lesions, it is an invasive procedure that can precipitate acute obstruction from edema or inflammation. A ventilating infant rigid bronchoscope with Hopkins optics should be kept above the critical area to avoid precipitating obstruction. Flexible transnasal awake bronchoscopy is most useful in demonstrating functional abnormalities (eg, malacia).

Treatment

Noncritical stenotic and malaciac lesions in infants and children should be managed as conservatively as possible, preferably without intubation. “Temporary” stenting of these lesions is seldom temporary, since the presence of the tube itself ensures continued trauma and irritation such that the tube cannot be removed without airway obstruction. If an infant or child cannot be managed without intubation, surgical correction must be considered. Tracheal reconstruction via resection or a variety of tracheoplasty techniques has proved to be the treatment of choice for tracheal lesions. Severe tracheomalacia is treated by addressing the underlying cause. Aortopexy or an endotracheal stent is often necessary. Tracheostomy is a last resort.

CONGENITAL DIAPHRAGMATIC HERNIA

CDH is a highly lethal or morbid disease that affects 1 in 2000 live births (Figure 43–6). Anatomically, CDH results from an embryologic fusion defect, allowing herniation of intra-abdominal contents into the chest. Fusion of the transverse septum and pleuroperitoneal folds normally occurs during the eighth week of embryonic development. If diaphragmatic formation is incomplete, the pleuroperitoneal hiatus (foramen of Bochdalek) persists. Intestinal nonrotation is common as the bowel herniates into the thorax rather than undergoing its normal sequence of rotation and fixation. Severe defects cause pulmonary hypoplasia, pulmonary hypertension, and cardiac dysfunction. The larger the hernia and the earlier it occurs, the more severe the pulmonary hypoplasia.

Clinical Findings

A. Symptoms and Signs

Infants with large diaphragmatic defects are usually symptomatic in the delivery room, with tachypnea, grunting respirations, retractions, and cyanosis, and may require urgent intubation. Smaller defects may not become symptomatic until the infant is several days or months old. Typically, the abdomen is scaphoid since much of the abdominal viscera are in the hemithorax. The chest on the side of the hernia may be dull to percussion, but bowel sounds are not usually appreciated. The left side of the diaphragm is affected four or five times as frequently as the right, with a rate of associated anomalies of 20% (chromosomal abnormalities, neural tube defects, and congenital heart disease). When the hernia is on the left, the heart sounds may be heard best on the right side of the chest.

The development of symptoms with CDH correlates with the degree of pulmonary hypoplasia and pulmonary hypertension. Prenatal diagnosis is occurring more and more frequently and allows the mother and the fetus to be referred to an institution where sophisticated perinatal and pediatric surgical units are available.

B. Imaging Studies

A chest radiograph may demonstrate the following: a paucity of gas within the abdomen, radiopaque hemithorax if the bowel does not contain a significant amount of gas or if the left lobe of the liver occupies the majority of the hemithorax, loss of normal ipsilateral diaphragmatic contour, bowel in the thorax, contralateral mediastinal shift, and a coiled nasogastric tube in the hemithorax. Right-sided hernias can be difficult to distinguish from a diaphragmatic eventration. This can be differentiated by an MRI scan. MRI or CT scan can also distinguish between CDH and a cystic lung lesion (eg, congenital cystic adenomatoid malformation).

Treatment

A nasogastric tube should be placed in the stomach to aspirate swallowed air and to prevent distention of the herniated bowel, which would further compress the lungs. Repair of the diaphragmatic defect is not a surgical emergency, it is rather a physiologic emergency requiring resuscitation, with surgery performed once the infant has stabilized and demonstrated minimal to no pulmonary hypertension. Early (before 48 hours postnatally) hernia repair has been shown to transiently worsen pulmonary function by decreasing pulmonary compliance and increasing airway reactivity. A subcostal abdominal incision should be made and the herniated bowel reduced from the pleural space. Some surgeons prefer a thoracic approach, particularly for right-sided defects. The negative pressure between the bowel and the chest wall may make reduction difficult. Following reduction of the bowel, placement of a chest tube in the pleural space is optional; if used, it is connected to a water seal and not to suction as it may cause physiologically significant mediastinal shift. The diaphragmatic defect should be closed by nonabsorbable sutures. In many instances, a synthetic material is required to close large defects. The abdominal cavity may be too small and underdeveloped to accommodate the intestine and permit closure of the abdominal wall muscle and fascial layers. In such cases, abdominal wall skin flaps should be mobilized and closed over the protruding bowel or a silo created to allow for gradual visceral reduction with concomitant abdominal domain expansion and staged closure of the abdominal wall.

Respiratory support and treatment of hypoxemia, hypercapnia, and acidosis are required before and often after repair. Persistent pulmonary hypertension may result in right-to-left shunt and produce severe hypoxemia in the lower aorta. Nitric oxide added to the ventilation gases can induce pulmonary vasodilation, improve pulmonary perfusion, and reverse the right-to-left shunt. The persistent fetal circulation physiology may be treated successfully in many cases by extracorporeal membrane oxygenation and permissive ventilatory strategies (high-frequency ventilation). Hypoxemic myocardiopathy may require infusion of dopamine to enhance cardiac output. Prenatal treatment for severe CDH (temporary fetal tracheal occlusion to promote lung growth) has been extensively studied and may offer benefit in severe cases of CDH.

Prognosis

The death rate for infants with CDH depends upon the severity of pulmonary hypoplasia, the presence or absence of associated anomalies, and the quality of care provided for these critically ill infants. When diagnosed in utero, prognosis depends on the presence or absence of liver herniation into the left hemithorax, the gestational age at diagnosis, and an ultrasonographic estimation of lung size (the lung-to-head ratio). Long-term, there are a number of measurable physiologic abnormalities that are not necessarily clinically significant such as a reduction in total lung volume, restrictive or obstructive lung disease, and abnormal lung compliance. However, a small subset of patients will survive as “pulmonary cripples” and remain oxygen dependent or ventilator dependent, often requiring tracheostomies. Since there may be deficient periesophageal muscular tissue or an abnormal orientation of the gastroesophageal junction, GER is common. It is most commonly treated nonoperatively, but refractory cases may require a surgical antireflux procedure. Recurrent diaphragmatic hernia occurs in 10%-20% of infants and should be considered in any child with a history of CDH who presents with new GI or pulmonary symptoms. Recurrence is most common when a prosthetic patch is used for the repair.

Surgical units that are immediately adjacent to obstetric services report death rates as high as 80%, because infants with severe pulmonary hypoplasia will be recognized and treated immediately. Infants who survive transfer to surgical centers remote from the delivery area usually have less severe disease, and the death rates reported from these facilities are usually under 40%.

With improvements in prenatal ultrasonographic imaging, many of these defects can be appreciated early enough so that planned delivery at a tertiary facility is possible. Excluding those infants with severe associated anomalies, the overall survival rate using maximal medical therapy has been increasing over the past several years due to advanced ventilation strategies and is well over 70%.

FORAMEN OF MORGAGNI HERNIA

The foramen of Morgagni occurs at the junction of the septum transversum and the anterior thoracic wall. This anterior, central diaphragmatic defect accounts for only 2% of diaphragmatic hernias. It may be parasternal, retrosternal, or bilateral. Unlike Bochdalek hernias, children are typically asymptomatic and the defect is discovered later in life on a chest radiograph taken for reasons unrelated to the hernia. The lateral chest radiograph demonstrating an air-filled mass extending into the anterior mediastinum is pathognomonic. Repair is indicated in the asymptomatic patient due to the risk of bowel obstruction. The viscera are reduced and any associated hernia sac excised. The defect is closed by suturing the posterior rim of diaphragm to the posterior rectus sheath since there is no anterior diaphragm. A prosthetic patch closure is frequently required given the tension that results with native tissue repairs given the absence of anterior diaphragm. Laparoscopic approaches to this type of repair are increasingly being performed. There is no associated pulmonary hypoplasia or hypertension. This defect, when noted in newborns, can be associated with the pentalogy of Cantrell, a disorder with considerable morbidity and mortality that consists of the anterior diaphragmatic defect, distal sternal cleft, epigastric omphalocele, apical pericardial defect, and congenital heart disease (usually a septal defect). Excluding patients with the pentalogy of Cantrell, survival is nearly 100%.

EVENTRATION OF THE DIAPHRAGM

Diaphragmatic eventration is an abnormally elevated or attenuated portion of the diaphragm (or both). It may be congenital (usually idiopathic, but can be associated with congenital myopathies or intrauterine infections) or acquired (as a result of phrenic nerve injury during forceps delivery or surgery). In the congenital form, there is variable thinning or absence of diaphragmatic muscle, at which point its distinction from CDH with a persistent hernia sac is obscure. The elevated hemidiaphragm may produce abnormalities of chest wall mechanics with impaired pulmonary function. Respiratory distress and pneumonia are frequent presenting symptoms, although GI symptoms such as vomiting or gastric volvulus have been reported.

The diagnosis is made by chest radiograph. It is confirmed by fluoroscopy or ultrasound, which demonstrate paradoxical movement of the diaphragm during spontaneous respiration. Incidentally discovered small, localized eventrations do not need repair. Eventrations that are associated with respiratory symptoms should be repaired by plicating the diaphragm using interrupted nonabsorbable sutures.

Congenital lobar emphysema results from hyperinflation of a single lobe; rarely, more than one lobe is affected. The upper and middle lobes are most frequently involved. Pathologically, there are three forms; hypoplastic emphysema, polyalveolar lobe, and bronchial obstruction.

Hypoplastic emphysema is distinguished by a segment, lobe, or whole lung that has a reduced number of bronchial branches with a diminished number and smaller size of blood vessels. The number of alveoli is abnormally decreased, but the air spaces are too large. The hyperlucent region seen on chest radiograph is normal or small in volume, and since it does not affect the surrounding normal lung, surgical treatment is unnecessary.

Polyalveolar lobe is characterized by a normal size and number of bronchial branches, but there is an abnormal number of alveoli from each respiratory unit. These alveoli are prone to expand excessively, producing emphysema, which encroaches on the surrounding normal lung and therefore requires removal.

Bronchial obstruction may occur from deficient bronchial cartilage support, redundant mucosa, bronchial stenosis, mucous plug, or bronchial compression by anomalous vessels or other mediastinal lesions. With inspiration, the bronchus opens to allow air into the lung, but on expiration the bronchus collapses, trapping the air, and with each respiratory cycle there is progressive expansion of the lobe.

Clinical Findings

In one-third of patients, respiratory distress is noted at birth; in only 5% of cases do symptoms develop after 6 months. Males are affected twice as frequently as females. The signs include progressive and severe dyspnea, wheezing, grunting, coughing, cyanosis, and difficulty feeding. An increased anteroposterior dimension of the chest and retractions may be seen. The chest is hyperresonant, and decreased breath sounds may be noted over the affected lobe. A chest radiograph may demonstrate radiolucency of the emphysematous lobe, with bronchovascular markings extending to the lung periphery. Compression atelectasis of the adjacent lung, shift of the mediastinum, depression of the diaphragm, and anterior bowing of the sternum can be seen. The emphysematous lobe may continue to expand, compressing adjacent lung and airways, producing progressively severe respiratory distress.

Treatment & Prognosis

Occasionally, the emphysema may be due to a foreign body or mucous plug in the bronchus that may be aspirated by bronchoscopy. Compression of the bronchus by mediastinal masses may be relieved by removal of the tumor or repair of anomalous vessels.

Treatment of asymptomatic and mildly symptomatic cases may not be necessary. Many patients with lobar emphysema, however, are severely symptomatic, and pulmonary lobectomy is necessary. For those who are breathing spontaneously prior to operation, anesthesia should not be started until all personnel are ready for a rapid thoracotomy since positive-pressure ventilation may acutely enlarge the emphysematous lobe, thereby compressing the normal lung tissue and heart. The prognosis following surgical relief of the lobar emphysema is excellent. Rarely patients may show residual disease in the remaining lung. At long-term follow-up, lung volumes are normal, but the airflow rates are diminished.

Tracheobronchial and esophageal compression by the great vessels may occur as a result of anomalies of the aortic arch or of abnormally located or enlarged pulmonary and subclavian arteries. While the most common abnormality is an aberrant right subclavian artery, the most important is the double aortic arch, as it often causes serious respiratory distress in young infants (Figure 43–7). Affected infants have a characteristic inspiratory and expiratory wheeze, stridor, or croup-like cough. Echocardiography, CT, and MRI can demonstrate the anomalous anatomy. Esophagoscopy and bronchoscopy may be helpful in assessing the degree and level of compression. The surgical approach is through the left hemithorax. Following removal of the thymus, the aortic arch and its branches are skeletonized and the anatomy is identified. For the double aortic arch, the smallest arterial component is divided; an anomalous right subclavian artery is divided at its origin. The accompanying fibrous bands and sheaths constricting the trachea and esophagus must also be divided. The ductus arteriosus (or its fibrous remnant) is also divided.

Mediastinal masses are relatively common in infants and children and can be classified according to the compartment of the mediastinum from which they arise. The mediastinum is classically divided into anterior, middle, and posterior compartments. Anatomically, the anterior mediastinum consists of the area between the sternum and the anterior aspect of the trachea and pericardium. The middle compartment contains the trachea, major bronchi, and paratracheal spaces. The posterior segment extends from the posterior aspect of the trachea to the spine.

Anterior masses make up one-third and are most commonly teratomas and lymphomas. Teratomas may be cystic or solid and may also be found within the pericardium (middle compartment). Approximately 20% are malignant. Other masses include thymic cysts, thymomas, substernal goiters, and lymphangiomas. Middle mediastinal masses are rare but when present are most likely to be bronchogenic cysts. Sixty percent of mediastinal masses are located within the posterior compartment. Neurogenic tumors are most common and include neuroblastoma, ganglioneuroblastoma, ganglioneuroma, neurofibroma, and neurofibrosarcoma. Common symptoms include respiratory distress (via tracheal or lung compression), Horner syndrome, and pain. Enterogenous cysts or duplications are also commonly seen in the posterior compartment. They are termed neurenteric when there is an associated cervical or thoracic vertebral anomaly.

Congenital lung lesions, which arise from anomalous development of the foregut, are classified as follows: (1) bronchogenic cyst, (2) congenital pulmonary airway malformation (CPAM), (3) pulmonary sequestration, and (4) bronchopulmonary foregut malformation. Embryonic tissues that are destined to form bronchi and lung become anomalous isolated structures within or outside of the lung. These lesions produce symptoms from their size and position, resulting in compression of bronchi or lung parenchyma, or from infection and abscess formation within the cyst and surrounding normal lung. There is a growing number of congenital lung lesions being diagnosed due to improvements in prenatal imaging. Most lesions warrant a postnatal CT angiogram to determine the anatomic location of the lesion and the presence of systemic feeding vessels.

BRONCHOGENIC CYST

Bronchogenic cysts are lined by cuboidal or ciliated columnar epithelium and are filled with mucoid material. Repeated infection in the cyst may produce squamous epithelial metaplasia. About half arise in the mediastinum and do not communicate with the bronchi. They appear as radiopaque masses on chest radiographs. When located within the lung parenchyma, the cysts usually communicate with the airways and consequently are prone to abscess formation. Bronchogenic cysts arise in the right lung three times more often than in the left. They are more common in the lower lobes but may be found in any lobe. Partial compression of bronchi produces hyperinflation of the involved lung, while complete obstruction produces atelectasis. Rupture of a cyst that communicates with bronchi may present as a tension pneumothorax. Treatment of a noninfected cyst is by excision. Infected cysts first require drainage (usually percutaneous) and intravenous antibiotic therapy followed by resection after the inflammation subsides (no sooner than 6 weeks after drainage).

CONGENITAL PULMONARY AIRWAY MALFORMATION

This lesion is a multicystic lung mass resulting from proliferation of terminal bronchiolar structures. It is typically lined by a polypoid proliferation of bronchial epithelium surrounded by striated muscle and elastic tissue, but there is an absence of mucous glands and cartilage. They are most often lobar and are classified radiologically based on cyst size: type I are large (> 2 cm) cysts, type II are smaller cysts (< 2 cm), and type III have cysts that are so small as to import a solid appearance. These malformations occur with equal frequency in both lungs, with a slight predominance in the upper lobes. Associated renal and nervous system anomalies may be present.

Clinical Findings

A large lesion can compress the fetal lung, resulting in pulmonary hypoplasia at birth, or may distort or obstruct the esophagus, producing polyhydramnios. In addition, compression of venous return to the heart with exudation of protein into the lung fluid may cause fetal congestive heart failure, hydrops fetalis, and death in utero. Large lesions that do not cause fetal hydrops can remain stable or involute during fetal life, producing little or no symptoms of respiratory distress at birth.

Treatment

If prenatal ultrasound can recognize the presence of this disorder in association with hydrops, resection in utero is an option for select cases. Steroids have recently shown promise in the prenatal treatment of CPAM with hydrops. Children in whom hydrops did not occur before birth may be born asymptomatic (small lesions) or may have variable degrees of respiratory distress due to compression of the ipsilateral normal lung. Asymptomatic children may be observed, but resection (pulmonary lobectomy) is recommended since these lesions often become infected and there are case reports of malignant transformation occurring in untreated, long-standing cysts. Often the plain chest radiograph does not demonstrate the small, asymptomatic lesion.

PULMONARY SEQUESTRATION & BRONCHOPULMONARY FOREGUT MALFORMATION

A sequestration consists of normally developed bronchioles and alveoli supplied by systemic rather than pulmonary arteries. Sequestrations occur in the lower chest, most commonly on the left, adjacent to the mediastinum. Rarely, sequestrations may occur in the upper or middle lobes or even below the diaphragm. They usually have a systemic arterial blood supply from the aorta, either above or below the diaphragm. On rare occasions, a sequestration will communicate with the esophagus or stomach, a condition termed bronchopulmonary foregut malformation. Sequestrations may be intralobar or extralobar. Intralobar lesions drain through the pulmonary veins, are in communication with the tracheobronchial tree, and are prone to infection and lung abscess formation. Extralobar lesions drain into the azygous venous system, do not communicate with the lung, and are commonly asymptomatic. They are often found in association with CDH. Histologic evidence suggests that these lesions have embryologic origin similar to that of bronchogenic cysts and congenital cystic adenomatoid malformations. However, unlike the latter, sequestrations rarely grow large enough to produce hydrops and demise in utero. Treatment is by excision of the extralobar sequestration or lobectomy in cases of intralobar sequestration.

ESOPHAGEAL ANOMALIES

The trachea and esophagus are derived from the primitive foregut. Initially, they appear as a common ventral diverticulum at about the nineteenth day of gestation. Beginning several days later, elongation and separation of the diverticulum into the airway and esophagus occurs in a caudal to cephalad direction. Errors in this process result in esophageal atresia, tracheoesophageal fistula, and their variants (Figure 43–8).

Classification

A. With Esophageal Atresia

1. There is a blind proximal pouch and a fistula between the distal end of the esophagus and the distal one-third of the trachea (type C, 85% of cases).

2. There is a blind proximal esophageal pouch, no tracheoesophageal fistula, and a blind, short distal esophagus (type A, 10% of cases). This is referred to as “pure or long gap” atresia.

3. There are fistulas between both proximal and distal esophageal segments and the trachea (type D, 2% of cases).

4. There is a fistula between the proximal esophagus and the trachea and a blind distal esophagus without fistula (type B, 1% of cases).

B. Without Esophageal Atresia

1. There is an “H”-type tracheoesophageal fistula that is usually present in the low cervical region (type E, 4%-5% of cases).

2. There is esophageal stenosis consisting of a membranous occlusion (often containing cartilage) between the mid and distal third of the esophagus (rare).

3. There is a laryngotracheoesophageal cleft of varying length, consisting of a linear communication between these structures (very rare).

Clinical Findings

Shortly after birth, the infant with esophageal atresia is noted to have excessive salivation and repeated episodes of coughing, choking, and cyanosis. Attempts at feeding result in choking, gagging, and regurgitation. Infants with tracheoesophageal fistula in addition to esophageal atresia will have reflux of gastric secretions into the tracheobronchial tree, with resulting pneumonia. Pulmonary infiltrates are usually noted first in the right upper lobe. Diagnosis may be delayed (several months) in cases of H-type tracheoesophageal fistula who are able to feed but may present with recurrent upper respiratory infections due to aspiration.

A size 10F catheter should be passed into the esophagus by way of the nose or mouth; if esophageal atresia is present, the tube will not go down the expected distance to the stomach and will coil in the upper esophageal pouch. If a tracheoesophageal fistula connects to the lower esophageal segment, air will be present in the stomach and bowel on plain radiographs. Absence of air below the diaphragm usually means that a distal tracheoesophageal fistula is not present.

Abdominal distention is a prominent finding because the Valsalva effect of coughing and crying forces air through a fistula into the stomach and bowel. The presence and position of the fistula can be determined by bronchoscopy.

Laryngotracheoesophageal cleft produces symptoms similar to those of tracheoesophageal fistula but of much greater severity. Laryngoscopy may show the cleft between the arytenoids extending down the larynx. Bronchoscopy is the best means of outlining the cleft.

There is a 50% incidence of associated anomalies: cardiac (patent ductus arteriosus, septal defects), GI (imperforate anus, duodenal atresia), genitourinary, and skeletal. The VACTERL association (vertebral, anorectal, cardiac, tracheoesophageal, renal, and limb anomalies) is present in 25% of cases. Isolated esophageal atresia has been associated with various genetic abnormalities, including trisomy 18 and trisomy 21. Echocardiogram, renal ultrasound, anorectal exam and genetic testing should be considered in the workup of all patients with TEF.

Treatment

A sump suction catheter should be placed in the upper esophageal pouch and the head of the bed elevated. An echocardiogram is required to determine the position of the aortic arch since a right-sided arch makes the standard right thoracotomy (or thoracoscopic) repair difficult and is present in 5% of infants. If possible, aspiration pneumonia is treated before repair.

The goal of operative therapy is to divide and ligate the fistula and repair the atresia in one stage, if possible. This is usually performed using a right posterolateral thoracotomy with an extrapleural dissection, although a transpleural thoracoscopic approach is gaining popularity for those stable, full-term infants. Also, thoracoscopic approaches are gaining acceptance as minimal invasive techniques continue to evolve. In those with an H-type tracheoesophageal fistula, the fistula is located above the thoracic inlet in two-thirds of cases. These fistulas may be divided through a left transverse cervical incision. A feeding gastrostomy tube is no longer routinely inserted except when the esophageal repair is under extreme tension, when there is long gap atresia not amenable to single-stage repair, and when there are severe associated anomalies (eg, congenital heart disease). A transanastomotic feeding tube is placed for postoperative feeding pending demonstration of a leak-free anastomosis by esophagogram obtained 7 days after surgery.

Staged operations are reserved for extremely premature babies, those who have severe aspiration pneumonitis, and those with severe anomalies or long gaps between the esophageal pouches. There are several strategies for repairing these defects. These include cervical esophagostomy, division of the fistula, and insertion of a gastrostomy tube. Several months later a staged reconstruction by esophageal replacement with colon or stomach interposition can be undertaken. Another alternative is a gastrostomy tube alone with intermittent bougienage and stretching of the upper esophageal pouch, followed by primary esophageal anastomosis and immediate interposition grafting.

Esophageal narrowing or webs in the distal esophageal segment readily respond to esophageal dilation. This is usually accomplished with Hurst or Maloney bougies. Dilations are repeated until healing occurs without recurrence of the web. Esophagoscopy and excision of portions of a tough or thick web, using biopsy forceps or the endoscopic laser, may be required in addition to dilation. A lower esophageal stricture containing cartilage requires excision and anastomosis.

Prognosis

The survival rate for a full-term infant without associated anomalies is excellent. However, deaths occur as a result of pulmonary complications, severe associated anomalies, prematurity, and sepsis due to anastomotic disruption. Anastomotic leaks occur because of tension or poor blood supply. In performing the anastomosis, the extrapleural approach prevents the development of empyema and confines a leak and possible infection to a small localized area.

Swallowing is a reflex response that must be reinforced early in infancy. If establishment of esophageal continuity is delayed for more than 4-6 weeks, it may take many months to overcome oral aversion and learn to swallow. Babies with cervical esophagostomies should be encouraged to suck, eat, and swallow during gastrostomy feedings.

Dysphagia may occur for months or years following successful repair of esophageal atresia and is multifactorial. An anastomotic stricture is not uncommon and may require one or more dilations under anesthesia. Swallowed foreign bodies will lodge at the site of anastomosis and require removal with esophagoscopy. Another cause of dysphagia is poor peristalsis of the distal esophageal segment. This frequent problem improves with age.

Most of these infants have an alarming, barking cough and rattling sound on respiration from tracheomalacia. This results from in utero compression of the trachea by the dilated proximal esophageal pouch. This frequently improves with age and is rare after 5 years of age. GER is common after successful repair and may result in recurrent aspiration pneumonitia, dysphagia, failure to thrive, and recurrent anastomotic stricture. Medical therapy with an H2-blocker or proton pump inhibitor should be instituted in all patients after repair and a surgical antireflux procedure may be necessary if medical therapy fails.

INTESTINAL OBSTRUCTION IN THE NEWBORN

Since fetuses continually swallow amniotic fluid into their GI tracts and excrete it in their urine, intestinal obstruction may be noted on prenatal ultrasound by the presence of polyhydramnios (increased amniotic fluid level). The presence of polyhydramnios correlates with the level of the obstruction; it is most common with proximal GI tract obstruction (eg, esophageal and duodenal atresia), is rarely noted with ileal atresia, and is never noted in association with anorectal obstruction.

After birth, vomiting is the principal symptom, and it is bile stained if the obstruction is distal to the ampulla of Vater. It is important to note that bilious vomiting in the newborn is pathologic until proved otherwise. On physical examination, the presence and degree of abdominal distention depends on the level of the obstruction and should be noted. For example, there is no significant distention with duodenal obstruction versus massive distention with colonic obstruction (eg, Hirschsprung disease). A careful perineal examination should be performed to determine whether the anus is present, patent, and in the normal location. Meconium, the first newborn stool, passes in the first 24 hours of life in 94% of normal full-term infants and by 48 hours in 98%. Failure to pass meconium may be indicative of lower GI tract obstruction. However, 30%-50% of newborn infants with intestinal obstruction will pass meconium.

Depending on the pathology, the plain abdominal radiograph may demonstrate dilated bowel loops, air-fluid levels, calcifications (if in utero perforation occurred), or a gasless abdomen. Unlike in adult patients, one cannot differentiate small from large bowel by their usual markings on a plain radiograph of the newborn’s abdomen. If a lower GI tract obstruction is suspected, a contrast (usually water-soluble contrast) enema is the most useful study since it can be both diagnostic and therapeutic in the majority of cases (see below). An upper GI series is rarely indicated unless malrotation is to be ruled out. The CT, MRI, or ultrasound scans are virtually never indicated in the workup of newborn intestinal obstruction.

HYPERTROPHIC PYLORIC STENOSIS

Pyloric stenosis is the most common surgical disorder producing emesis in infancy. It results from hypertrophy of the circular and longitudinal muscularis of the pylorus and the distal antrum of the stomach with progressive narrowing of the pyloric canal (Figure 43–9). The cause is not known. The male:female incidence is 4:1. The disorder is more common in firstborn infants and occurs four times more often in the offspring of mothers who had the disease as infants than in those whose fathers had the disease. If one monozygotic twin is affected, the other will also have the disorder in two-thirds of cases. A seasonal variation is noted in the occurrence of symptoms, with peaks in spring and fall.

Clinical Findings

A. Symptoms and Signs

Typically, the affected infant is full term when born and feeds and grows well until 2-4 weeks after birth, at which time occasional regurgitation of some of the feedings occurs. Several days later, however, the vomiting becomes more frequent and forceful. The vomitus contains the previous feeding and no bile. Blood may be seen in the vomitus in 5% of cases, and coffee grounds or occult blood is frequently present. Shortly after vomiting, the infant acts starved and will feed again. The stools become infrequent and firm in consistency as dehydration occurs. With dehydration, infants often have sunken fontanelles, dry mucous membranes, and poor skin turgor. Weight loss follows progressive feeding intolerance. Jaundice with indirect hyperbilirubinemia occurs in fewer than 10% of cases. Gastric peristaltic waves can usually be seen moving from the left costal margin to the area of the pylorus. In over 90% of cases, the pyloric “tumor,” or “olive,” can be palpated when the infant is relaxed. Abdominal relaxation may be accomplished by sedating the infant or by feeding clear fluids and simultaneously aspirating the stomach contents with a gastric tube.

B. Imaging Studies

An imaging study is indicated when the pyloric tumor cannot be palpated. Abdominal ultrasound, the most sensitive and specific test, will identify hypertrophic pyloric stenosis when the muscle thickness is greater than 4 mm and the length of the pylorus is greater than 16 mm. A dynamic ultrasound may also show no passage of ingested fluid. A contrast upper GI series is indicated if an experienced ultrasonographer is unavailable or if there is a reasonable chance that the patient’s symptoms are not due to pyloric stenosis (eg, a premature, 1-week-old baby) since this examination can demonstrate other entities in the differential. A positive upper GI series can include the following diagnostic signs: (1) outlining of the narrow pyloric channel by a single “string sign” or “double track” owing to folds of mucosa; (2) a pyloric “beak” where the pyloric entrance from the antrum occurs; (3) the “shoulder” sign, in which the pyloric mass bulges into the antrum; and (4) complete obstruction of the pylorus.

Differential Diagnosis

Repeated nonbilious vomiting in early infancy may be due to overfeeding, intracranial lesions, pylorospasm, antral web, GER, pyloric duplication, duodenal stenosis, malrotation of the bowel, or adrenal insufficiency.

Complications

Repeated vomiting with inadequate intake of formula results in hypokalemic hypochloremic alkalosis, dehydration, and starvation. Gastritis and reflux esophagitis occur frequently. Aspiration of vomitus may produce pneumonia.

Treatment & Prognosis

The operative treatment is the Fredet-Ramstedt pyloromyotomy, in which the pylorus is incised along its entire length, spread widely exposing but not breaching the underlying mucosa. Surgery should be undertaken only after dehydration and the hypokalemic hypochloremic alkalosis have been corrected, heralded by a normal serum chloride (which is a proxy for a normal serum bicarbonate) as well as a urine output greater than 1 cc/kg/h. There are three approaches to the pyloromyotomy: a right upper quadrant transverse skin incision, a circumumbilical or intraumbilical skin incision, or a laparoscopic approach with the telescope in the umbilicus and the two working instruments placed directly through the abdominal wall. The laparoscopic approach offers advantages in postoperative recovery with equivalent outcomes in experienced hands. Successful myotomy is evident when the submucosa is seen to herniate out of the myotomy site. If, during the pyloromyotomy, the mucosa is inadvertently entered (usually on the duodenal side), it is closed with fine nonabsorbable sutures and an omental patch is placed. Large perforations are managed by closing the pyloromyotomy, rotating the pylorus 90 degrees, and repeating the myotomy.

Multiple postoperative feeding schedules have been described, ranging from immediate full feeds to delayed feeds with incremental advances in volume. This has stemmed from the observation that nearly all patients with pyloric stenosis vomit after surgery, presumably due to gastric ileus, gastritis, GER, or all of the above. An incomplete pyloromyotomy (usually on the antral side) is suspected when vomiting persists beyond 1-2 weeks postoperatively and stems from a short myotomy or incomplete division of the muscle. Incomplete myotomy should be evaluated by upper GI series as ultrasound will likely show ongoing hypertrophy.

Pyloric stenosis never recurs, and there is a uniformly excellent outcome.

CONGENITAL DUODENAL OBSTRUCTION

The various causes of duodenal obstruction are atresia, stenosis, mucosal web (complete or variably perforate), annular pancreas, preduodenal portal vein, and peritoneal bands (Ladd bands) from malrotation. Duodenal atresia is distinguished from more distal GI atresias since it is due to failure of recanalization of the duodenum early in gestation rather than due to mesenteric vascular abnormality late in gestation. Atresia of the duodenum is twice as common as in the jejunum or ileum. In about half of cases, multiple congenital anomalies are present, including Down syndrome in 30% and congenital heart disease in 20%. Birth weight is less than 2500 g in half of these infants. Mucosal webs or stenoses occur as often as pure atresia. Annular pancreas is almost always associated with hypoplasia of the duodenum at the level of the ampulla. The cause is a developmental defect characterized by circumferential persistence of the gland around the duodenum at the site of the embryonic ventral anlage, leading to duodenal obstruction and an accessory pancreatic duct.

Clinical Findings

In 75% of cases, duodenal obstruction occurs distal to the ampulla of Vater, causing bile to be diverted to the proximal duodenum and stomach. Bilious emesis occurs shortly after birth and during attempted feedings. The upper abdomen is rarely distended. Meconium is passed in over 50% of cases.

The plain abdominal radiograph demonstrates an air-distended stomach and duodenum (“double bubble” sign). Gas in the small and large intestine indicates incomplete obstruction. Contrast upper GI series is used to identify the presence or absence of malrotation in those cases with incomplete obstruction since obstruction from intestinal malrotation is a surgical emergency.

Treatment

Surgery is performed using a right upper transverse abdominal incision or via laparoscopy. A Kocher maneuver should be performed, with complete mobilization of the third and fourth portions of the duodenum. Obstruction from Ladd bands requires simple division of the bands and correction of the malrotation (see below). Duodenoduodenostomy is performed for duodenal atresia and annular pancreas. A mucosal web can be excised if technically feasible, taking care to avoid injury to the adjacent ampulla. Commonly, the duodenum is hugely dilated above the obstruction, which results in impaired aboral progression of ingested feedings. This problem is resolved by excision or plication of a portion of the antimesenteric wall of the bowel to normalize the lumen diameter (tapered duodenoplasty). Gastrojejunostomy should not be done because the blind duodenal pouch may cause repeated vomiting. The distal bowel should be irrigated and assessed for associated intrinsic obstruction if possible. However, the rate of associated distal atresia is low (0.5%-3% incidence) and most commonly seen in conjunction with an “apple peel” deformity). Mortality is related to prematurity and associated anomalies.

ATRESIA & STENOSIS OF THE JEJUNUM, ILEUM, & COLON

Atresia and stenosis of the jejunum, ileum, and colon are caused by a mesenteric vascular accident in utero, which may result from hernia, volvulus, or intussusception, producing aseptic necrosis and resorption of the necrotic bowel. Although atresia may occur in any portion of the intestine, most cases occur in the distal ileum or proximal jejunum. Colonic atresia is very rare, accounting for no more than 1% of all intestinal atresias. A short area of necrosis may produce only stenosis or a membranous web occluding the lumen (type I) (Figure 43–10). A more extensive infarct may leave a fibrous cord between the two bowel loops (type II), or the proximal and distal bowel may be completely separated with a V-shaped defect in the mesentery (type IIIa). Multiple atresias occur in 10% of cases (type IV). A type III variant (type IIIb) is commonly called apple-peel or Christmas tree atresia, in which there is a blind-ending proximal jejunum, absence of a long length of mid small bowel, and a terminal ileum coiled around its tenuous blood supply from an ileocolic vessel.

Clinical Findings

Vomiting of bile, abdominal distention, and failure to pass meconium indicate intestinal obstruction. The plain abdominal radiograph will give an estimate of how far along the intestine the obstruction exists. A contrast enema may be indicated to detect the level of obstruction. In obstructions that occur in the distal bowel and appear relatively early in gestation, the colon is empty of meconium and appears abnormally narrow (microcolon). When the obstruction is proximal or when it occurs late in pregnancy, meconium is passed into the colon. The contrast enema will then outline a more generous-sized colon with its contents (meconium). In older children with evidence of partial intestinal obstruction, a small bowel series may be indicated to identify intestinal stenosis.

Treatment

There are three main goals of operation: (1) to restore the continuity of the bowel; (2) to preserve as much intestinal length as possible; and (3) to retain the ileocecal valve if possible (the minimum length of bowel needed to sustain full enteral nutrition doubles in the absence of the ileocecal valve). A transverse upper abdominal incision is preferred. Infants with jejunal or ileal atresia usually have a segment of the proximal bowel adjacent to the atresia that is dilated out of proportion to the rest of the proximal bowel. This is referred to as the “club” and it lacks normal peristaltic activity. If left in or not tapered, it may become a source of persistent functional obstruction. It is tapered when it is a very proximal bowel segment, near the ligament of Treitz; otherwise it should be resected. A great discrepancy between the diameter of the segments of intestine proximal and distal to the atresia is the rule. Atresia of the proximal colon should be treated by resection of the dilated bowel and ileocolostomy. Atresia of the distal colon may be treated by proximal end colostomy or by a side-to-side colostomy. Later, the continuity of the distal colon may be established by end-to-end anastomosis.

Infants born with extensive small bowel loss may benefit from a Bianchi procedure, where the entire greatly dilated bowel is divided longitudinally into two lengths of bowel. An alternative bowel lengthening procedure termed the STEP (serial transverse enteroplasty procedure) is quickly gaining acceptance as the procedure of choice for gaining length from dilated and shortened intestine. The end of the jejunum in continuity with the duodenum is anastomosed to the proximal end of the divided bowel.

In contrast to duodenal atresia, associated anomalies are unusual in small bowel and colon atresia. Following repair, return of GI function can be prolonged and feeds should be introduced accordingly.

DISORDERS OF INTESTINAL ROTATION

The fetal intestine begins as a somewhat straight tube that grows faster than the abdominal cavity and thus herniates out into the body stalk (future umbilicus) at about 4-6 weeks’ gestation. At 10-12 weeks, the bowel returns to the abdominal cavity, rotates, and becomes fixed to the retroperitoneum along a long diagonal axis extending from the level of the left of the T12 vertebra to the level of the right of the L5 vertebra. The duodenojejunal portion of gut rotates posterior (counterclockwise) to the superior mesenteric vessels for 270 degrees and becomes fixed at the ligament of Treitz and located to the left of and cephalad to the superior mesenteric artery. The cecocolic portion of the midgut also rotates 270 degrees, but clockwise (anterior) to the superior mesenteric artery. The cecum becomes fixed in the right lower abdomen (L5 level).

Classification

Anomalies of rotation and fixation are twice as common in males as in females. They may be classified as (1) nonrotation, (2) incomplete rotation, (3) reversed rotation, and (4) anomalous fixation of the mesentery.

A. Nonrotation

With nonrotation, the midgut is suspended from the superior mesenteric vessels; the small bowel is located predominantly on the right side of the abdomen and the large bowel in the left abdomen. No fixation occurs, and adhesive bands are not present. This is the fetal anatomy prior to 10 weeks’ gestation. Because its base is so short, the mesentery is narrow, which predisposes to volvulus, with clockwise twisting of the bowel about the superior mesenteric vessels. This anomaly is usually found in patients with omphalocele, gastroschisis, and CDH.

B. Incomplete Rotation

Incomplete rotation (commonly called malrotation) may affect the duodenojejunal segment, the cecocolic segment, or both. Adhesive bands (Ladd bands) are usually present. In the most common form, the cecum stops rotating and fixes near the origin of the superior mesenteric vessels, and dense peritoneal bands extend from the right flank to the cecum and obstruct the second or third portion of the duodenum or other segments of the small bowel. The duodenojejunal segment also only partially rotates, usually stopping at or to the right of the vertebral bodies. The intestinal mesentery is fixed posteriorly, but is very narrow, only extending the distance between the cecum and the duodenojejunal segment. This predisposes to volvulus (Figure 43–11).

C. Reversed Rotation

In reversed rotation, the bowel rotates varying degrees in a clockwise direction about the superior mesenteric axis. The duodenojejunal loop is anterior to the superior mesenteric artery. The cecocolic loop may be prearterial or may be rotated clockwise or counterclockwise in a retroarterial position. In either case, the cecum may be right sided or left sided. The most frequent anomaly is retroarterial clockwise rotation, which causes obstruction of the right colon.

D. Anomalous Fixation of Mesentery

Anomalies of mesenteric fixation account for internal mesenteric and paraduodenal hernias, a mobile cecum, or obstructing adhesive bands in the absence of anomalous bowel rotation. Excessive rotation of the duodenojejunal junction may result in superior mesenteric artery compression of the third portion of the duodenum.

Clinical Findings

A. Symptoms and Signs

Anomalies of intestinal rotation may cause symptoms related to intestinal obstruction, peptic ulceration, or malabsorption. The majority of patients who develop intestinal obstruction are infants. Older patients may develop intermittent obstruction. The obstruction is in the duodenum or upper jejunum as a result of adhesive bands or midgut volvulus, respectively. Vomiting of bile occurs initially. Older patients may be thin and underweight because of chronic postprandial discomfort or malabsorption. Malabsorption with steatorrhea may result from partial venous and lymphatic obstruction, which is associated with coarse rugal folds in the small bowel. With duodenal obstruction from bands, abdominal distention is not prominent. Midgut volvulus, however, produces marked abdominal distention. Bloody stools and signs of peritonitis are manifestations of intestinal infarction. Peptic ulcer occurs in 20% of patients, presumably as a result of antral and duodenal stasis.

B. Imaging Studies

With obstructing Ladd bands, plain abdominal radiographs may show a “double bubble” sign that mimics duodenal stenosis. Distribution of gas throughout the intestines may be normal, although there may be a paucity of it. When volvulus occurs, the proximal bowel will be distended with gas early, but over time, a “gasless” abdomen may appear as the gas is resorbed in the ischemic bowel. The intestinal walls are thickened.

The identification of inverted superior mesenteric artery and superior mesenteric vein position on ultrasound is highly suggestive of malrotation and warrants further investigation; however, ultrasound can miss 10%-15% of cases. Upper GI series is the gold standard for diagnosis and demonstrates distention of the duodenum, abnormal positioning of the duodenojejunal segment (usually to the right of the midline), and narrowing at the point of obstruction. The small bowel is commonly visualized on the right side of the abdomen and the colon on the left. Contrast enema demonstrates abnormal position of the cecum, although the cecum can complete its rotation and fixation after birth, so the contrast enema is not a valuable diagnostic test for malrotation.

Treatment & Prognosis

Through a transverse upper abdominal incision, the entire bowel should be delivered from the abdominal cavity to assess the anomalous arrangement of the intestinal loops. Volvulus should be untwisted in a counterclockwise direction. The Ladd procedure is used for incomplete rotation with obstruction of the duodenum by congenital bands. It consists of division of the bands between the proximal colon and the lateral abdominal wall that cover and compress (obstruct) the duodenum. The mesentery is often folded upon itself due to intermesenteric adhesions, and these are incised. The appendix is removed. The cecum is then placed in the left lower quadrant, and the duodenum dissected and straightened as much as possible with a final position to the right of the midline. In essence, one is creating nonrotated intestinal anatomy much like the anatomic situation in early fetal life (prior to 10 weeks’ gestation). The Ladd procedure has increasingly been performed using laparoscopic techniques for those cases without suspected volvulus.

Approximately 30% of infants treated for volvulus die of complications of midgut ischemia and gangrene. If the anomaly is corrected before irreversible bowel damage occurs, the long-term results are good. Some patients tend to form adhesions that cause recurrent intestinal obstruction. Recurrent volvulus is rare after the Ladd procedure.

MECONIUM ILEUS

In 10%-20% of infants born with cystic fibrosis, the thick mucous secretions of the small bowel produce obstruction by inspissated meconium. This usually occurs in the terminal ileum. Although there is no clear correlation between pancreatic insufficiency and the development of inspissated meconium, meconium ileus also occurs in patients with pancreatic duct obstruction and pancreatic aplasia. Meconium obstruction with no apparent cause has also been described in newborn infants.

Clinical Findings

A. Symptoms and Signs

The infant typically has a normal birth weight and very distended abdomen. No meconium is passed, and bilious emesis occurs early. Loops of thick, distended bowel may be seen and palpated.

B. Imaging Studies

Plain abdominal radiographs show loops of bowel that vary greatly in diameter; the thick meconium gives a ground-glass appearance. Air mixed with the meconium produces the “soap bubble” sign, which is usually located in the right lower quadrant. Radiographs taken shortly after the infant has been placed in an upright position may fail to show air-fluid levels because the thick, viscid meconium fails to layer out rapidly. Contrast enema will show microcolon with rare meconium flecks. Reflux of contrast medium through the ileocecal valve demonstrates a small terminal ileum containing “pellets” of inspissated mucus; more proximally, the bowel is progressively distended with packed meconium. Antenatal perforation may be detected by the presence of abdominal calcifications since the meconium becomes saponified.

Complications

Meconium ileus may be complicated by a segmental (not midgut) volvulus due to the heavy, distended loops of distal ileum. If this occurs early in fetal life, the volvulus may progress to gangrene of the affected bowel segment. This can heal completely, with abdominal calcifications as the only manifestation that it occurred. Conversely, it may heal in such a way that an intestinal atresia is formed. Perforation late in gestation may lead to meconium peritonitis or a large meconium pseudocyst at birth.

Other common complications of meconium ileus are related to the almost universal presence of cystic fibrosis. These infants are susceptible to repeated pulmonary infection with chronic bronchopneumonia, bronchiectasis, atelectasis, and lung abscess. Malabsorption due to pancreatic insufficiency requires pancreatic enzyme replacement. Rectal prolapse and intussusception may be produced by strained passage of inspissated stools. Nasal polyps and chronic sinusitis are frequent. Biliary cirrhosis and bleeding varices from portal hypertension are late manifestations of bile duct obstruction by mucus.

Treatment & Prognosis

Nonoperative treatment is successful in 60%-70% of cases. A nasogastric tube should be inserted and connected to suction. A contrast enema can be both diagnostic and therapeutic. It should be performed with a slightly hypertonic water-soluble contrast agent (never barium). The addition of N-acetylcysteine, which is mucolytic, may be necessary to disperse the meconium in uncomplicated cases. The infant must be well hydrated, and intravenous fluids must be continued during and after the procedure in order to prevent hypovolemia from the effects of the hypertonic contrast solution. If this fails to relieve the obstruction, laparotomy is indicated. The ileum is opened and, if possible, flushed clear. The bowel can be reanastomosed or brought out as a double-barrel stoma. Alternatively, a T-tube may be placed in the bowel and brought out of the anterior abdominal wall for postoperative irrigations. Compromised intestine is resected, and appendectomy is performed because of the high rate of appendicitis in patients with cystic fibrosis.

All patients should be evaluated for cystic fibrosis. Pancreatic enzyme replacement may be required. A formula low in long-chain fatty acids and high in medium-chain triglycerides may give better absorption and growth than standard formulas. The patient must be placed in an environment with high humidity to keep tracheobronchial secretions fluid. Postural drainage with cupping of the chest should be taught to the parents so that they will continue to maintain tracheobronchial toilet indefinitely. Older children and adolescents may develop a meconium ileus-like syndrome termed distal ileal obstruction syndrome. This is ileal obstruction due to inspissated stool. It can occur when patients are not compliant with their medications or become dehydrated. Most often, it is successfully treated with hypertonic contrast enemas.

HIRSCHSPRUNG DISEASE

Hirschsprung disease is due to failure in the cephalocaudal migration of the parasympathetic myenteric nerve cells into the distal bowel. Therefore, the absence of ganglion cells always begins at the anus and extends a varying distance proximally. The aganglionic bowel produces functional obstruction because the bowel fails to relax in response to distention. Short-segment aganglionosis involving only the terminal rectum occurs in about 10% of cases; the disease extends to the sigmoid colon in 75%; more proximal colon in 10%; and the entire colon with small bowel involvement in 5%. Extensive involvement of the small bowel is rare.

Males are affected four times more frequently than females when the disease is limited to the rectosigmoid. Females tend to have longer aganglionic segments. A familial association occurs in 5%-10% of cases—more frequently when females are affected. The length of involvement tends to be consistent in familial cases. Down syndrome occurs in 10%-15% of patients.

Clinical Findings

A. Symptoms and Signs

The absence of ganglion cells results in a functional obstruction since the affected area fails to relax due to unopposed sympathetic tone. The symptoms vary widely in severity but almost always occur shortly after birth. The infant passes little or no meconium within 24 hours. Thereafter, chronic or intermittent constipation usually occurs. Progressive abdominal distention, bilious emesis, reluctance to feed, diarrhea, listlessness, irritability, and poor growth and development follow. A rectal examination in the infant may be followed by expulsion of stool and flatus, with remarkable decompression of abdominal distention. In older children, chronic constipation and abdominal distention are characteristic. Passage of flatus and stool requires great effort, and the stools are small in caliber. Children with constipation from Hirschsprung disease do not exhibit soiling of their diapers or undergarments, distinguishing this form of constipation from idiopathic constipation (encopresis). These children are sluggish, with wasted extremities and flared costal margins. Rectal examination in older children usually reveals a normal or contracted anus and a rectum without feces. Impacted stools in the greatly dilated and distended sigmoid colon can be palpated across the lower abdomen.

B. Imaging Studies

Plain abdominal radiographs in infants show dilated loops of bowel, but it is difficult to distinguish small and large bowel in infancy. A contrast enema should be performed. There should be no rectal examination or attempt to clean out the stool before the fluoroscopic examination, for this can dilate the rectum and obscure the change in caliber between aganglionic and ganglionic bowel. The contrast enema often demonstrates a contracted (aganglionic) segment that appears relatively narrow compared with the dilated proximal bowel. The proximal aganglionic intestine can be dilated by impacted stool or enema, giving a false impression of the level of the normal colon. Irregular, bizarre contractions (saw-toothed pattern) that do not encircle the aganglionic portion of the bowel may also be recognized. The dilated proximal bowel may have circumferential, smooth, parallel contractions (similar in appearance to those of the jejunum) that are exaggerated contraction waves. The contrast enema may not show a transition zone in the first 6 weeks after birth, since the liquid stool can pass into the aganglionic bowel and the proximal intestine may not be dilated. Lateral projection radiographs should be taken to demonstrate the rectum, the transition zone, and the irregular contractions that may otherwise be obscured by a redundant sigmoid colon on anteroposterior views. Normally, the neonatal rectum is wider than the rest of the colon (including the cecum), and when the rectum is seen to be narrower than the proximal colon, then Hirschsprung disease is suspected. Radiographs of the abdomen and lateral pelvis should be repeated after 24-48 hours. The contrast agent will be retained for prolonged periods, and saline enemas may be required to evacuate it. The delayed film may show the transition zone and the bizarre irregular contractions more clearly than the initial study.

C. Laboratory Findings

Definitive diagnosis is made by rectal biopsy. Mucosal and submucosal biopsies may be taken from the posterior rectal wall with a suction biopsy capsule at the bedside. Serial sections may demonstrate the characteristic lack of ganglion cells and proliferation of nerve trunks in Meissner plexus. If the findings are equivocal, it is necessary to remove a 1-cm or 2-cm full-thickness strip of mucosa and muscularis from the posterior rectum proximal to the dentate line under anesthesia. A sample of this size is sufficient for the pathologist to determine the presence or absence of ganglion cells in Meissner plexus or in Auerbach plexus. Manometric studies will show a failure of relaxation of the internal sphincter following rectal distention by a balloon, although this test is rarely performed except in older children.

Differential Diagnosis

Low intestinal obstruction in the newborn infant may be due to rectal or colonic atresia, meconium plug syndrome (see below), or meconium ileus as well as a variety of functional causes such as hypermagnesemia, hypocalcemia, hypokalemia, and hypothyroidism. Hirschsprung disease in patients who develop enterocolitis and diarrhea may mimic other causes of diarrhea. Chronic constipation due to functional causes may suggest Hirschsprung disease. Although functional constipation may occur early in infancy, the stools are normal in caliber, soiling is frequent, and enterocolitis is rare. In functional constipation, stool is palpable in the lower rectum, and a contrast enema shows uniformly dilated bowel to the level of the anus. However, short segment Hirschsprung disease may be difficult to differentiate, and rectal biopsy may be necessary. Segmental dilation of the colon is a rare entity that causes constipation similar to that found in Hirschsprung disease.

Treatment

Traditionally, the surgical treatment was staged and consisted of a leveling colostomy followed several months later by resection of the aganglionic bowel and performance of a pull-through procedure. The trend recently has been toward performing a single-stage procedure (no colostomy) in the newborn period. This paradigm is as follows: bowel obstruction and enterocolitis (if present) may be relieved by placement of a large (30F) rectal tube and repeated warmed saline irrigations in 10 mL/kg aliquots preoperatively. Infants with moderate to severe enterocolitis should be treated with a diverting colostomy. At the time of surgery, frozen section analysis of the colonic muscle is required in order to establish the correct (ganglionic) level for the stoma. Infants who are not ill may undergo any one of three effective operative procedures: Swenson operation, Duhamel operation, or Soave operation. The main operative principles for these procedures are removal of most or all of the aganglionic bowel—while preserving the surrounding nerves to the pelvic organs—and anastomosing ganglionic bowel (confirmed by frozen section analysis) to the rectum just above the dentate line. In contrast to the Swenson and Soave procedures, the Duhamel operation leaves a cuff of aganglionic rectum along which the ganglionic bowel is stapled, creating a mini-reservoir. Historically, these operations have been performed via a low transverse abdominal incision. However, the laparoscopic approach has become the method of choice. A solely transanal mucosectomy has been used for those babies with short-segment disease. In total aganglionic colon, ileostomy is necessary. Nonoperative treatment with enemas is ineffective because it fails to prevent further obstruction and enterocolitis.

Prognosis

The mortality for untreated aganglionic megacolon in infancy may be as high as 80%. Nonbacterial, nonviral enterocolitis is the principal cause of death. This tends to occur more frequently in infants but may appear at any age. The cause is not known but seems to be related to the high-grade partial obstruction, poor motility in the “normal” bowel, a frequently competent ileocecal valve, and hypertonic rectal sphincters. There is no correlation between the length of aganglionosis and the occurrence of enterocolitis. Perforation of the colon and appendix may result from distal bowel obstruction. Atresia of the distal small bowel or colon secondary to bowel obstruction due to Hirschsprung disease in utero has been reported.

Anastomotic leak with perirectal and pelvic abscess is the most serious complication following the pull-through procedure. This complication should be treated immediately by proximal colostomy until the anastomosis has healed. Necrosis of the pulled-through colon may occur if the bowel has not been mobilized sufficiently to prevent tension on the mesenteric blood supply.

Long-term patients who are properly treated for Hirschsprung disease do well. Incontinence and soiling may occur in a few cases despite a prompt diagnosis and a perfect operation. Episodic constipation and abdominal distention are more common, since the aganglionic internal anal sphincter is intact. Patients with these symptoms can respond to anal dilation. Occasionally, an internal sphincterotomy may be necessary. Smaller children may still develop enterocolitis after definitive treatment, and they should be treated with a large rectal tube and enemas. It is rare after age 5 years. Postoperative enterocolitis is more common in children with Down syndrome.

NEONATAL SMALL LEFT COLON SYNDROME (MECONIUM PLUG SYNDROME)

This problem of newborn infants consists of low intestinal obstruction associated with a left colon of narrow caliber and a dilated transverse and right colon. The infants are in most cases otherwise normal, though approximately 30%-50% are born to diabetic mothers and are large for gestational age. Most are over 36 weeks’ gestational age and have normal birth weights. Two-thirds are male. Hypermagnesemia has been occasionally associated when the mother has been treated for eclampsia by intravenous magnesium sulfate.

Clinical Findings

Rectal examination may be normal or may reveal a tight anal canal. Little or no meconium is passed, and progressive abdominal distention is followed by vomiting. After thermometer or finger stimulation of the rectum, some meconium and gas may be evacuated. Contrast enema shows a very small left colon, usually to the level of the splenic flexure. Proximal to this point, the colon and commonly the small bowel are greatly distended. In about 30% of cases, a meconium plug is present at the junction of the narrow and dilated portion of the bowel, and the enema (using water-soluble contrast) will dislodge it.

Differential Diagnosis

The small left colon syndrome may be confused with Hirschsprung disease or meconium ileus. These lesions rarely cause obstruction at the level of the splenic flexure, and when the colon readily decompresses without further obstruction, Hirschsprung disease is unlikely.

Treatment

A nasogastric tube should be inserted and intravenous fluids started. A contrast enema is required to differentiate the various causes of low intestinal obstruction. When the left colon is narrow and contrast material refluxes into the dilated proximal colon, the diagnosis is most likely the small left colon syndrome. The contrast enema is usually followed by evacuation of copious meconium and decompression of the bowel. Incomplete evacuation of the meconium or persistent symptoms after the enema mandates a suction rectal biopsy to rule out Hirschsprung disease.

INTUSSUSCEPTION

Telescoping of a segment of bowel (intussusceptum) into the adjacent segment (intussuscipiens) is the most common cause of intestinal obstruction in children between 6 months and 2 years of age (Figure 43–12). The process of intussusception may result in gangrene of the intussusceptum. The most common form is intussusception of the terminal ileum into the right colon (ileocolic intussusception). In 95% of infants and children, it is idiopathic. The disease is most common in midsummer and midwinter, and there is a correlation with adenovirus infections. In most cases, hypertrophied Peyer patches are noted on the leading edge of bowel. Mechanical factors such as Meckel diverticulum, polyps, hemangioma, enteric duplication, intramural hematoma (Henoch-Schönlein purpura), and intestinal lymphoma are present with increasing frequency in patients over 2 years old. Postoperative intussusception can occur at any age, is usually ileoileal or jejunojejunal, and is due to differential return of bowel motility, often after retroperitoneal surgery. The ratio of males to females is 3:2. The peak age is in infants 5-9 months of age; 80% of patients are under the age of 2 years.

Clinical Findings

The typical patient is a healthy child who suddenly begins crying and doubles up because of abdominal pain. The pain occurs in episodes that last for about 1 minute, alternating with intervals of apparent well being. Reflex vomiting is an early sign, but vomiting due to bowel obstruction occurs late. Blood from venous infarction and mucus produce a “currant jelly” stool. In small infants and in postoperative patients, the colicky pain may not be apparent; these babies become withdrawn, and the most prominent symptom is vomiting. Pallor and sweating are common signs during colic. Repeated vomiting and bowel obstruction will produce progressive dehydration. A mass is usually palpable along the distribution of the colon, most commonly in the right upper quadrant of the abdomen. Occasionally, intussusception is palpable on rectal examination. Prolonged intussusception produces edema and hemorrhagic or ischemic infarction of the intussusceptum.

Treatment & Prognosis

The contrast enema is diagnostic as well as therapeutic in 60%-80% of cases (Figure 43–13). Contrast enema (using either barium or air) should not be attempted until the patient has been resuscitated enough to allow an operative procedure to be performed safely. It is contraindicated if peritonitis is present. If barium is used, the column of contrast should not stand more than 100 cm above the patient in order to minimize the risk of perforation. Air is pumped into the colon at a pressure of 60-80 mm Hg (never > 120 mm Hg). A successful study reduces the intussusceptum and demonstrates reflux of barium or air into the terminal ileum. Several attempts should be made before taking the child to surgery. A contrast enema will not reduce gangrenous bowel.

Operation is required for unsuccessful enema reduction or signs of bowel perforation and peritonitis. The procedure may be performed either by laparotomy or laparoscopically. In the absence of gangrene, reduction is accomplished by gentle retrograde compression of the intussuscipiens, not by traction on the proximal bowel. Resection of the intussusception is indicated if the bowel cannot be reduced or if the intestine is gangrenous.

Intussusception recurs after 5% of enema reductions and 1% of operative reductions. Deaths are rare but occur if treatment of gangrenous bowel is delayed.

ANORECTAL ANOMALIES (IMPERFORATE ANUS)

The normal continence mechanism for bowel control consists of an internal sphincter composed of smooth muscle and the striated muscle complex from the levator ani and external sphincter. The striated muscles assume a funnel shape, originating from the pubis, pelvic rim, and sacrum. These muscles converge at the perineum while interdigitating with the internal and external sphincters. Most of the striated muscle complex consists of horizontal muscles that contract against the wall of the rectum and anus while longitudinal muscle fibers run in a cephalocaudal direction and elevate the anus.

Anomalies of the anus result from abnormal growth and fusion of the embryonic anal hillocks. The rectum is normally developed, and the sphincter mechanism is usually intact. With proper surgical treatment, the sphincter will function normally. Anomalies of the rectum develop as a result of faulty division of the cloaca into the urogenital sinus and rectum by the urorectal septum. In these anomalies, the internal sphincter and striated muscle complex are hypoplastic. Therefore, surgical repair results in varying degrees of continence.

Classification

Physical examination of the perineum and imaging studies determine the extent of malformation of the anus or rectum. When an orifice is evident at the perineum or distal introitus, the anomaly is referred to as a low imperforate anus; the absence of an obvious orifice at the perineal level suggests a high imperforate anus (Figures 43–14, 43–15, 43–16, and 43–17) In most instances, with high imperforate anus, there is a communication (fistula) of the rectum with the urethra or bladder in the male or with the upper vagina in the female. Distinguishing between a high and low anomaly may be possible radiologically by determining the position of the rectum in relation to the levator ani or pubococcygeal line.

A. Low Anomalies

In low anomalies, the anus may be ectopically placed anterior to its normal position or it may be in the normal position with a narrow outlet due to stenosis or an anal membrane. There may be no opening in the perineum, but the skin at the anal area is heaped up and may extend as a band in the perineal raphe completely covering the anal opening. A small fistula usually extends from the anus anteriorly to open in the raphe of the perineum, scrotum, or penis in the male or the vulva in the female. These babies often have well-developed perineal and gluteal musculature and rarely have sacral vertebral anomalies.

B. High Anomalies

In high anomalies, the rectum may end blindly (10%), but more commonly there is a fistula to the urethra or bladder in the male or the upper vagina in the female. In the female, a very high fistula may extend between the two halves of a bicornuate uterus directly to the bladder. Patients with high imperforate anus often have deficient pelvic and gluteal innervation and musculature, a high incidence of sacral anomalies (caudal regression), and a poor prognosis for continence after surgical repair. The most severe of the high deformities is a cloacal anomaly in which there is a common channel between the poorly developed pelvic structures (urogenital sinus and rectum) with a single perineal opening.

Clinical Findings

A. Signs

The best means of establishing the type of anorectal anomaly is by physical examination. In low anomalies, an ectopic opening from the rectum can be detected in the perineal raphe in males or in the lower vagina, vestibule, or fourchette in females. A high anomaly exists when no orifice or fistula can be seen upon examination of the perineum or when meconium is found at the urethral meatus, in the urine, or in the upper vagina. Absence of external sphincter contraction with cutaneous stimulation of the anus may also help differentiate between high and low lesions.

B. Imaging Studies

No single test is ideal in the evaluation of imperforate anus, so several studies are used to define the neonatal anatomy. Radiographs are sometimes useful when the clinical impression is unclear. A lateral film of the pelvis with the baby inverted (Wangensteen invertogram), once commonly used, is an inaccurate method of establishing the lower extent of the rectum because swallowed air may not have completely displaced the meconium from the rectum; or the striated muscle complex may be contracted, which obliterates the lumen and makes it look as if the gas in the rectum ends high in the pelvis. With crying or straining, the puborectalis muscle and rectum may actually descend below the ischium, giving a falsely low estimate of rectal height. Gas in the bladder clearly indicates a rectourinary fistula. Lower abdominal and perineal ultrasound, CT, and MRI have been used to define the pelvic anatomy and location in relation to the rectal musculature. Anomalies of the vertebrae and the urinary tract occur in two-thirds of all patients with high anomalies and in one-third of male patients with low anomalies. Vertebral abnormalities in females invariably indicate a high imperforate anus. Anomalies of the sacrum warrant MRI of the lumbosacral area to identify spinal cord anomalies such as a tethered filum terminale.

Complications

Associated anomalies occur in up to 70% in those with a high anomaly. Imperforate anus is associated with the VACTERL syndrome (see Esophageal Anomalies). The possible constellation of anomalies includes esophageal atresia, anomalies of the GI tract, hemivertebrae or agenesis of one or more sacral vertebrae (agenesis of S1, S2, or S3 is associated with corresponding neurologic deficits, resulting in neuropathic bladder and greatly impaired continence), genitourinary anomalies (up to 50% incidence with high imperforate anus), and anomalies of the heart and upper limbs/digits.

Delay in diagnosis of imperforate anus may result in excessively large bowel distention and perforation. The presence of a rectourinary fistula allows reflux of urine into the rectum and colon, and absorption of ammonium chloride may cause acidosis. Colon contents will reflux into the urethra, bladder, and upper tracts, producing recurrent pyelonephritis.

Treatment

The three main goals of treatment are (1) to allow passage of stool (ie, relieve obstruction), (2) to place the rectal pouch on the perineum in good position, and (3) to close the fistula.

A. Low Anomalies

Low anomalies are usually repaired from the perineal approach in the newborn period using a muscle stimulator to precisely determine the location of the sphincter complex. The anteriorly placed anal opening is completely mobilized and transferred to the normal position. After healing, the anal opening must be dilated daily for 3-5 months to prevent stricture formation and to allow for growth.

B. High Anomalies

Traditionally, a high deformity was treated by a three-stage repair consisting of colostomy and mucous fistula formation, a posterior sagittal anorectoplasty 4-6 weeks later, and closure of the colostomy several months after that. Recently, the staged approach has been challenged and a one-stage repair has been performed by both posterior sagittal and laparoscopic approaches. Because the anal sphincters are poorly developed—especially the internal sphincter—continence is most dependent upon a functioning striated muscle complex, which requires conscious voluntary contraction. Care must be taken to preserve the afferent and efferent nerves of the defecation reflex arc as well as the existing sphincter muscles. In all cases, the surgically created anus must be dilated for several months to prevent circumferential cicatrix formation.

Prognosis

Surgical complications include damage to the nervi erigentes, resulting in poor bladder and bowel control and failure of erection. Division of a rectourethral fistula some distance from the urethra produces a blind pouch prone to recurrent infection and stone formation, while cutting the fistula too short may result in urethral stricture. Erroneously attempting to repair a high anomaly from the perineal approach may leave a persistent rectourinary fistula. An abdominoperineal pull-through procedure performed for a low anomaly invariably produces an incontinent patient who might otherwise have had an excellent prognosis. Injury to the vas deferens and ureter is possible during repair of high anomalies.

Patients with imperforate anus tend to have varying degrees of constipation as an inherent part of the defect, believed to be due to poor inherent motility of the rectosigmoid. Patients with low anomalies usually have good sphincter function. Children with high anomalies do not have an internal sphincter that provides continuous, unconscious, and unfatiguing control against soiling. However, in the absence of a lower spine anomaly, perception of rectal fullness, ability to distinguish between flatus and stool, and conscious voluntary control of rectal discharge by contraction of the striated muscle complex can be achieved. When the stools become liquid, sphincter control is usually impaired in patients with high anomalies.

GASTROESOPHAGEAL REFLUX

Studies of esophageal motility, including manometric measurements of the cardioesophageal junction, show absence of the high-pressure zone (lower esophageal sphincter) in the terminal esophagus in most normal newborns. Evolution to the normal adult pattern of peristalsis and cardioesophageal sphincter function occurs after several months. Until this happens, many infants experience varying degrees of regurgitation after feeding. Rarely, repeated gastric reflux may produce peptic esophagitis and interfere with the development of a competent sphincter. Unlike adults, children rarely have a hiatal hernia as a cause of GER.

Clinical Findings

A. Symptoms and Signs

Symptoms consist of repeated effortless regurgitation of feedings, particularly when the baby is placed in a recumbent position. The baby will be hungry and will readily feed after regurgitating. Persistent regurgitation may result in poor weight gain (failure to thrive), peptic esophagitis with appearance of blood in the vomitus, or occult bleeding, producing anemia. One cause for apnea and acute life-threatening events (ALTE) is GER and aspiration. Lesser degrees of aspiration, particularly during sleep, may produce recurrent pneumonia. Stricture formation of the lower esophagus and metaplasia of the esophageal mucosa, producing Barrett esophagus, are possible late effects. Almost half of infants and children with GER have neurologic disorders related to perinatal asphyxia or congenital nervous system anomalies; seizure disorders are very common in this population. Abnormal motility of the esophagus and gastric dysmotility and impaired gastric emptying are frequently present. Gastroesophageal reflux is associated with esophageal atresia, CDH, and abdominal wall defects.

B. Imaging Studies

The standard diagnostic test is lower esophageal 24-hour pH monitoring. An upper GI series is less sensitive but is useful to rule out other disorders (eg, intestinal malrotation) and to assess for esophageal stricture. Gastric emptying may be assessed by technetium pertechnetate scan. There is virtually no role for esophageal manometric studies in young children except for those in whom one suspects the relatively rare achalasia or diffuse esophageal spasm.

Treatment

Nonoperative treatment is successful in most cases. Feedings should be thickened with rice cereal, and GER is lessened if the baby is maintained upright in an infant seat or in a prone position after feeding. Persistent symptoms mandate drug therapy with an antacid (eg, H₂-blocker or proton pump inhibitor) with or without a prokinetic agent (eg, metoclopramide). If a prolonged trial of nonoperative therapy fails or if complications of reflux can be documented (ie, esophagitis, stricture, asthma, recurrent aspiration pneumonia, failure to thrive), an antireflux procedure is indicated. The Nissen fundoplication has become the standard surgical treatment, although many variations on fundoplication exist. The open operation has been virtually replaced by the more cosmetic laparoscopic procedure that also provides for better visualization.

ACUTE APPENDICITIS

Acute appendicitis is one of the most common causes of an acute abdomen in childhood. This diagnosis must be considered in all age groups, but it is most common between the ages of 4 and 15 years.

Clinical Findings

The diagnosis is most often made by obtaining a careful clinical history and performing a thorough physical examination. In some patients, observation and periodic reexamination by the same physician may be necessary to confirm or exclude the diagnosis. In young children, the diagnosis of appendicitis can be difficult to arrive at, as the clinical history may be difficult to elicit. The classic presentation includes the onset of epigastric or periumbilical pain followed by anorexia, nausea, and vomiting. Anorexia is a significant finding, as the child will often refuse favorite foods. A fever will usually develop, and the pain then localizes to the right lower quadrant. Rovsing sign (right lower quadrant pain during palpation of the left lower quadrant), localized right lower quadrant tenderness, and involuntary spasm of the right hemirectus muscle indicate the presence of peritonitis.

A white blood count with differential and urinalysis should be obtained. The white blood cell count is greater than 10,000/μL (often with a left shift) in more than 80% of patients with appendicitis. Radiologic evaluation should include a chest film to exclude right lower lobe pneumonia. Findings on flat and erect abdominal radiographs are often nonspecific, though they may infrequently demonstrate the presence of a fecalith. Ultrasound (particularly in females) and CT scans are being used with increasing frequency, especially for those without the classic history and physical examination results.

Differential Diagnosis

Gastroenteritis is often confused with appendicitis. Vomiting follows periumbilical pain in appendicitis but often precedes abdominal pain in gastroenteritis. In addition, the patient with gastroenteritis commonly has diffuse abdominal pain and frequent copious watery diarrhea. Intussusception, intestinal obstruction and volvulus, mesenteric adenitis, Meckel diverticulitis, Henoch-Schönlein purpura, ruptured ovarian cyst, and Crohn disease must also be considered in the differential diagnosis for children. In adolescent girls, information regarding the menstrual cycle, previous episodes of pelvic inflammatory disease, and an accurate sexual history is important to exclude gynecologic causes of an acute abdomen.

Treatment

Once the diagnosis is made, fluid resuscitation is performed and antibiotics are administered. Appendectomy is accomplished through a right lower quadrant incision or laparoscopically. In cases of perforation, the peritoneal cavity is irrigated and aspirated dry but drainage is not performed, unless there is a mature abscess cavity. The wound is closed in all cases. Antibiotics are continued for 3-7 days or until the white blood cell count and fever normalize. Overall, the morbidity and mortality of appendicitis in children have gradually decreased with the increased use of powerful broad-spectrum antibiotics. However, perforated appendicitis with abscess formation remains the variant with increased morbidity when compared to nonperforated cases. Interval appendectomy after management of perforated appendicitis with antibiotics and abscess drainage when necessary is a viable option. The criteria for which patients to initially manage nonoperatively are still under debate.

DUPLICATIONS OF THE GASTROINTESTINAL TRACT

Duplications may occur at any point along the GI tract from the mouth to the anus. Duplications occur (in order of decreasing frequency) in the ileum (50% of cases), mediastinum, colon, rectum, stomach, duodenum, and neck. Intrathoracic and small bowel duplications are usually spherical; colonic duplications are commonly long and tubular (Figure 43–18). Characteristically, the intra-abdominal spherical duplications are on the mesenteric side of the intestine and do not share a common wall with the intestine.

Based on embryology, duplications have been categorized as foregut, midgut, and hindgut. Foregut duplications include the pharynx, respiratory tract, esophagus, stomach, and the first portion and proximal half of the second portion of the duodenum. Midgut duplications include the distal half of the second part of the duodenum, the jejunum, ileum, cecum, appendix, the ascending colon, and the proximal two-thirds of the transverse colon. The hindgut is composed of duplications of the distal third of the transverse colon, the descending and sigmoid colon, the rectum, anus, and components of the urologic system. Combined thoracoabdominal duplications also occur in which the thoracic saccular component extends through the esophageal hiatus or a separate diaphragmatic opening to empty into the duodenum or jejunum. A thoracic duplication, associated with a cervical or thoracic vertebral anomaly, in which the duplication communicates with the subarachnoid space, is called a neurenteric cyst. Associated cardiovascular, neurologic, skeletal, urologic, and GI anomalies occur in more than a third of cases. Carcinoma may arise within intestinal duplications later in life.

Clinical Findings

A. Symptoms and Signs

Two-thirds of patients with duplications are symptomatic in the first year of life. Duplications of the neck and mediastinum produce respiratory distress by compression of the airway. Thoracic duplications may ulcerate into the lung and lead to pneumonia or hemoptysis. Intestinal duplications usually produce abdominal pain owing to spastic contraction of the bowel, excessive distention of the duplication, or peptic ulceration and bleeding resulting from ectopic gastric mucosa in the duplication. Intestinal obstruction due to intussusception, volvulus, or encroachment on the lumen by an intramural cyst also occurs. An isolated asymptomatic mass may be the only finding. Sixty percent of duplications are diagnosed by 6 months of life and 85% by 2 years.

B. Imaging Studies

Studies include radiographs of the chest and thoracolumbar spine, CT scan of the chest and abdomen, contrast enema, esophagography, and upper GI series. If an intraspinal extension of a duplication is suspected, MRI is indicated. Ultrasonography may show a cystic or tubular mass within the mediastinum or abdomen. A Meckel scan (technetium pertechnetate) can also be used to visualize those duplications with ectopic gastric mucosa.

Treatment

Duplications not intimately adherent to adjacent organs should be excised. Isolated spherical duplications can be excised with the adjacent segment of bowel and an end-to-end anastomosis of the bowel performed. Long tubular duplications can be decompressed by establishing an anastomosis between the proximal and distal ends of adjacent bowel. Noncommunicating duplications, which would require radical resection of surrounding structures, should be drained by a Roux-en-Y technique. Duplications that cannot be removed completely and which contain gastric mucosa should be opened (without jeopardizing the blood supply of the normal bowel) and the mucosal lining excised. Extension of a mediastinal duplication into the spine or abdomen should be resected. An intra-abdominal extension is closed at the level of the diaphragm, and complete excision by laparotomy is accomplished.

OMPHALOMESENTERIC DUCT ANOMALIES

The omphalomesenteric (vitelline) duct is a remnant of the embryonic yolk sac. When the entire duct remains intact postnatally, it is recognized as an omphalomesenteric fistula. When the duct is obliterated at the intestinal end but communicates with the umbilicus at the distal end, it is called an umbilical sinus. When the epithelial tract persists but both ends are occluded, an umbilical cyst or intra-abdominal enterocystoma may develop. The entire tract may be obliterated, but a fibrous band may persist between the ileum and the umbilicus (Figure 43–19).

The most common remnant of the omphalomesenteric duct is Meckel diverticulum, which is present in 1%-3% of the population. Meckel diverticulum may be lined wholly or in part by small intestinal, colonic, or gastric mucosa, and it may contain aberrant pancreatic tissue. Heterotopic tissue is found in 5% of asymptomatic and 60% of symptomatic cases. In contrast to duplications and pseudodiverticula, Meckel diverticulum is located on the antimesenteric border of the ileum, 10-90 cm from the ileocecal valve. Meckel diverticulum occurs with equal frequency in both sexes. It is usually asymptomatic and is seen as an incidental finding during operation for other disease. Of those with Meckel diverticulum, the lifelong risk of complications is 4%, and 40% of these cases occur in children under 10 years of age.

Clinical Findings

Symptomatic omphalomesenteric remnants (male:female incidence 3:1) produce painless rectal bleeding in 40%, intussusception in 20%, diverticulitis or peptic perforation in 15%, umbilical fistula in 15%, intestinal obstruction in 7%, and abscess in 3% of cases. Rectal bleeding associated with Meckel diverticulum is due to peptic ulceration of the adjacent ileum caused by ectopic gastric mucosa. Over 50% of these patients are under 2 years of age. The blood is mixed with stool and is most often dark red or bright red; tarry stools are unusual. A history of a previous episode of bleeding may be elicited in 40% of cases. Occult bleeding from Meckel diverticulum is very rare. Younger patients tend to bleed quite briskly and may exsanguinate rapidly. Diverticulitis or free perforation will present with abdominal pain and peritonitis similar to acute appendicitis. The pain and tenderness occur in the lower abdomen, most commonly near the umbilicus. Periumbilical cellulitis may be present.

Intestinal obstruction may develop as a result of volvulus of the bowel about a persistent band between the umbilicus and the ileum or as a result of herniation of bowel between the mesentery and a persistent vitelline or mesodiverticular vessel. Obstruction is the most common presentation in adults. An infected umbilical sinus or omphalomesenteric fistula may present with mucoid, purulent, or enteric discharge, recurrent cellulitis, or a deep abdominal wall abscess about the umbilicus. This can be diagnosed by cannulation and contrast injection via the umbilical tract.

Upper and lower contrast studies rarely outline the primary defect. Technetium Tc 99m pertechnetate may localize in gastric mucosa lining Meckel diverticulum and may identify the source of hematochezia or melena. Retention of dye in the mucous and parietal cells is enhanced by giving cimetidine, 30 mg/kg intravenously, 30 minutes before administration of the radiotracer nuclide.

Treatment

Resection is accomplished by laparotomy or laparoscopy. An omphalomesenteric remnant with a narrow base may be treated by amputation and closure of the bowel defect (usually with a surgical stapler). In cases where the anomaly has a wide mouth with ectopic tissue or where an inflammatory or ischemic process involves the adjacent ileum, intestinal resection with the diverticulum and anastomosis may be necessary.

NECROTIZING ENTEROCOLITIS

Necrotizing enterocolitis (NEC) is the most serious and frequent GI disorder of predominantly premature infants, with a median onset of 10 days after birth. The incidence is increasing given the therapeutic advances in neonatal intensive care that have allowed ever more premature infants to survive. It is characterized by necrosis, ulceration, and sloughing of intestinal mucosa, which frequently progresses to full-thickness necrosis and perforation. This process progresses from the submucosa through the muscular layer to the subserosa. Gas-producing bacteria in the intestinal wall may lead to pneumatosis, a finding that may be noted on gross examination as well as on plain abdominal radiographs. The terminal ileum and right colon are usually affected first, followed in descending order of frequency by the transverse and descending colon, appendix, jejunum, stomach, duodenum, and esophagus. The most extreme case, pan-necrosis, is defined as necrosis of 75% or more of the bowel. Eighty percent of cases occur in premature infants weighing less than 2500 g at birth, and 50% are under 1500 g. However, the disorder may also occur in full-term infants. Contrary to earlier impressions, there is no established relationship between NEC and stressful perinatal events such as premature rupture of membranes with amnionitis, breech delivery, intrauterine bradycardia, umbilical vessel catheterization with or without exchange transfusion, respiratory distress syndrome, sepsis, omphalitis, and congenital heart disease. An associated patent ductus arteriosus is common. In older infants and children, NEC is usually preceded by malnutrition and gastroenteritis. The clustering of cases in nurseries suggests that an infectious agent may be responsible.

Clinical Findings

Clinical findings include increased gastric residual, bilious vomiting, abdominal distention, bloody stools, lethargy, and poor skin perfusion. When intestinal perforation occurs, guarding is evident on abdominal examination, but in weak premature infants this may not be obvious. There are a variety of nonspecific clinical findings that suggest physiologic instability such as apnea, bradycardia, hypoglycemia, and temperature instability. On examination, abdominal distention and fixed loops of intestine may be appreciated. The presence of abdominal wall erythema, edema, and crepitus may be a sign of bowel necrosis. Laboratory evaluation is nonspecific since the white blood cell count may be low or high, but thrombocytopenia and acidosis develop with perforation and sepsis.

Supine and cross-table lateral abdominal radiographs show small bowel distention early, followed by pneumatosis intestinalis. Gas within the portal venous system can be seen but it is fleeting. Serial examinations may show a loop or loops of bowel that are fixed in position and dilated. Perforation with peritoneal air develops in 20% of cases. Infants who develop ascites without pneumoperitoneum should have paracentesis and examination of the fluid for bacteria, which would signify perforation. Contrast studies are hazardous and contraindicated, as they may easily lead to perforation.

Treatment

Treatment includes cessation of feedings, orogastric suction, systemic antibiotics, and correction of hypoxemia, hypovolemia, acidosis, and electrolyte abnormalities. The only absolute indication for intervention is pneumoperitoneum. Relative indications are portal vein air, clinical deterioration, a fixed intestinal loop on serial radiographs, erythema of the abdominal wall, an abdominal mass, and a paracentesis demonstrating bacteria. At laparotomy, necrotic bowel is resected and the proximal bowel is made into a stoma. Rarely is primary anastomosis safe. Severe disease may not be amenable to operation or require extensive bowel resection, resulting in short bowel syndrome. An alternative treatment option in very low-birth-weight (VLBW) infants (< 1500 g) that is gaining acceptance for documented perforation is bedside drainage of the peritoneal cavity in the right lower quadrant using local anesthesia. A recent prospective randomized trial comparing laparotomy to drain placement for VLBW infants demonstrated equivalent outcomes in mortality and short-term morbidity for these two modalities.

In one-third of cases, the disorder resolves without further treatment, and the overall survival rate is more than 50%. Intestinal stricture may occur as a late complication following healing. For this reason, a contrast enema is used to evaluate the defunctionalized distal bowel before closing the stoma.

GASTROINTESTINAL BLEEDING

Significant GI bleeding in children is rare. When it occurs, it can be alarming and anxiety provoking for caregivers and parents. The diagnostic approach used in the evaluation of these children is similar to that used in adults, but the causes vary depending on the age of the child. Rarely is the GI bleeding massive, and the majority of causes are benign. A diagnosis can be established in over 85% of cases. Usual presenting symptoms include hematemesis, hematochezia, and melena. Depending on the amount of bleeding, the child may have sunken fontanelles, dry mucous membranes, and cool skin. Tachycardia, oliguria, and hypotension may be present. Intravenous access should be obtained, fluid and blood administered as needed, and an evaluation begun. Laboratory tests include serial hematocrit measurements and coagulation studies. Following stabilization and physical examination, evaluation should then proceed to the appropriate diagnostic tests.

Upper Gastrointestinal Bleeding

Upper GI bleeding originates above the ligament of Treitz. The presence of melena and the presence of blood on passage of an orogastric tube can help differentiate between upper and lower GI bleeding. Upper GI bleeding in infants and young children is most often associated with stress ulcers or erosions, but in older children it may also be caused by duodenal ulcer, esophagitis, and esophageal varices particularly in children with underlying liver disease. The majority of these diseases are benign. Evaluation following stabilization of the child begins with flexible esophagoduodenoscopy. Once the diagnosis is made, treatment is usually amenable to antacids (H₂-blockers, proton pump inhibitors). Variceal hemorrhage may require more aggressive intervention, including the use of octreotide, endoscopic varix sclerosis or band ligation, and, in extreme cases, transjugular intrahepatic portocaval shunt (TIPS), mesocaval shunt, or liver transplantation.

Lower Gastrointestinal Bleeding

Although diverticulitis, cancer, and angiodysplasia are the most common causes of lower GI bleeding in adults, those diseases are rare in children. The causes of lower GI bleeding in infants and children can be categorized in diagnostic age groups where the age of the patient, the amount of bleeding, and the color of the blood passed provide some guidance to the probable source of bleeding.

Bleeding in the neonate may be caused by swallowing maternal blood at delivery, an anorectal fissure, upper GI bleeding secondary to gastritis or ulceration, necrotizing enterocolitis, volvulus, and an incarcerated hernia. The Apt test for maternal blood, physical examination of the rectum and inguinal canal, and evaluation of the upper GI tract can quickly rule out most of these causes. Bleeding from necrotizing enterocolitis is rarely life threatening, and the diagnosis is commonly made based on the premature delivery of the infant and radiologic evaluation. If bleeding from malrotation with midgut volvulus is suspected, prompt laparotomy is indicated.

In infants, anal fissures continue to be the most common cause of rectal bleeding. Other causes include intestinal volvulus, intussusception, intestinal duplication, Meckel diverticulum, milk or formula protein allergy and infectious diarrhea. Contrast studies and appropriate stool cultures guide treatment. Children have a differential diagnosis similar to that of infants with the addition of rectal prolapse and a variety of polyps of the colon (juvenile, Peutz-Jeghers, polypoid lymphoid hyperplasia, and, rarely, adenomatosis). These entities are diagnosed by physical examination and proctosigmoidoscopy. If no source of bleeding is identified, colonoscopy is indicated, while capsule endoscopy is gaining acceptance as a diagnostic modality for occult causes of GI bleeding in appropriately sized patients. Juvenile polyps are the single most common cause of lower GI bleeding in children (20%-30%). Most juvenile polyps are single (80%) and often pass spontaneously without treatment. However, when bleeding continues to occur, the polyp can be snared and excised endoscopically. Adolescents may manifest signs and symptoms of inflammatory bowel disease (ulcerative colitis, Crohn disease), familial adenomatous polyposis, and small vascular lesions such as telangiectasias. Diagnosis is made by colonoscopy, and treatment is disease specific.

GASTROINTESTINAL FOREIGN BODIES

Children aged 9 months to 2 years are at particular risk for the ingestion or aspiration of foreign bodies given their newly acquired mobility, curiosity, and the tendency to place objects in their mouths. The type of foreign body and the location in the airway or GI tract dictate management.

Esophagal Foreign Bodies

Typical foreign bodies found in the esophagus include coins, food, and small toys. The three most common sites of obstruction are at the level of the cricopharyngeus muscle, at the level of the aortic arch, and at the gastroesophageal junction. Previous areas of repair/anastomosis as in esophageal atresia or injury predispose to obstruction due to scar and narrowing. Common symptoms include drooling, feeding intolerance, dysphagia, and pain. Perforation is rare but is dictated by the ingested object’s shape, composition, and time in the esophagus. The diagnosis is easily obtained by anteroposterior chest or lateral neck radiography if the ingested object is radiopaque. Otherwise, esophagoscopy or an upper GI series is needed.

Because of the risk of erosion, aspiration, perforation, and late stricture, impacted objects should be removed. Extraction can be performed using balloon catheter retrieval under fluoroscopic control or under direct visualization using esophagoscopy with general anesthesia. The latter technique is generally preferred if the nature of the object is unknown, or is sharp, or the ingestion was 24-48 hours previously. A Hopkins rod lens endoscopy system allows visualization of the object and retrieval with specially designed forceps for grasping small objects.

Ninety-five percent of foreign bodies that pass beyond the gastroesophageal junction proceed uneventfully through the GI tract. Operative retrieval is reserved for batteries, which must be removed, and for cases where ingested objects cause obstruction (bezoars), intestinal injury or have been in place for more than 1 week.

Tracheal Foreign Bodies

Children, particularly those 1-2 years of age, can occlude the airway by aspiration of a foreign body. The most common objects are peanuts and popcorn. Obstruction tends to occur at the level of the laryngeal inlet, the subglottis, or the right main stem bronchus. Because this can be a life-threatening problem, witnessed events should be treated with back blows, abdominal thrusts, or the Heimlich maneuver, which may dislodge the object.

Symptoms include coughing, choking, wheezing, dyspnea, and fever. Unilateral wheezing and rhonchi may be present. Air trapping may result when the foreign-body forms a ball-valve obstruction leading to hyperinflation of the affected lung and mediastinal shift away from the affected side. On the other hand, complete obstruction may lead to loss of air volume with atelectasis and mediastinal shift to the ipsilateral side. Inspiratory and expiratory radiographs or bilateral decubitus films in infants may demonstrate air trapping; the foreign body is rarely noted on radiographs.

With a worrisome history, a foreign body suggested on a radiograph, or any symptoms, the child should undergo bronchoscopic evaluation under general anesthesia. Working in tandem with the anesthesiologist to allow ventilation during rigid endoscopy, the foreign body can be readily identified. Lighted grasping forceps made specifically for foreign-body extraction are placed through the sheath of the bronchoscope; the foreign body is grasped; and the forceps, foreign body, and sheath are removed as one unit. Rarely, an unrecognized aspirated foreign body presents as chronic lung infection and can require removal of the affected lung.

Jaundice in the first 2 weeks of infancy is usually due to indirect (unconjugated) hyperbilirubinemia. The causes include (1) “physiologic jaundice” due to immaturity of hepatic function (eg, that associated with breast-feeding); (2) Rh, ABO, and rare blood group incompatibilities, which produce hemolysis; and (3) infections. Jaundice that persists beyond the first 2 weeks in which the indirect and conjugated bilirubin levels are elevated should prompt a more thorough workup aimed at diagnosing potential surgical disorders. The most frequent cause (60%) of prolonged jaundice in infancy is biliary atresia; various forms of hepatitis occur in 35%; and choledochal cyst is found in 5% of cases of obstructive jaundice. Intestinal obstruction can intensify jaundice by increasing the enterohepatic circulation of bilirubin. Finally, jaundice is an early and important sign of sepsis in the newborn.

BILIARY ATRESIA

Biliary atresia is the absence of patent bile ducts draining the liver. Familial cases and frequent association with the polysplenia syndrome indicate a congenital onset. However, biliary atresia probably develops after birth because jaundice is not usually remarkable in the newborn period but becomes evident more than 2 weeks later. Furthermore, conjugated bilirubin is not cleared by the placenta as unconjugated bilirubin is, and jaundice due to conjugated hyperbilirubinemia with biliary obstruction has not been recognized in newborn infants. The atretic ducts consist of solid fibrous cords that may contain occasional islands of biliary epithelium.

The extent of duct involvement varies greatly. There are three anatomic patterns of obstruction: (1) the proximal extrahepatic bile ducts are patent and the ducts distal to the cystic duct are obliterated; (2) the gallbladder, cystic duct, and common bile duct are patent and the proximal hepatic ducts are occluded; and (3) the entire extrahepatic ductal system is obstructed. Liver biopsy demonstrates proliferation of the bile canaliculi containing inspissated bile. Over time, the failure to excrete bile out of the liver results in progressive periportal fibrosis and obstruction of the intrahepatic portal veins, resulting in biliary cirrhosis.

Clinical Findings

A. Symptoms and Signs

The infant with biliary atresia often has an uneventful neonatal course until jaundice is noted at 2-3 weeks of age. Stools may be normal or clay colored, and the urine may be dark. The stools contain an increased quantity of fat but are of normal consistency and not frothy. The liver may be of normal size early, but it becomes enlarged with time. A hard liver may develop as a consequence of progressive cirrhosis. Splenomegaly usually develops. Ascites and portal hypertension do not become manifest for several months.

B. Laboratory Findings

The workup of biliary atresia consists of analysis of liver function tests, complete blood count, and metabolic and serologic screening. The bilirubin levels may vary considerably from day to day, but direct bilirubin levels over 3 mg/dL are common. Alkaline phosphatase levels are often elevated to 500-1000 U/L, and γ-glutamyltranspeptidase levels are greater than 300 U/L.

C. Imaging Studies

Ultrasonography may demonstrate absence or inability to visualize a contracted gallbladder. Radionuclide scanning using technetium Tc 99m-labeled iminodiacetate compounds (IDA, HIDA, PIPIDA, DISIDA) to observe the intensity of uptake within the liver and evidence of secretion into the bowel is valuable, usually preceded by a 2- to 3-day course of phenobarbital to promote tracer uptake. Core needle biopsy of the liver may be safely performed at any age if the clotting tests are normal. A diagnosis based on needle biopsy is accurate in 60%, equivocal in 16%, and erroneous in 24% of cases. Unless the workup has conclusively diagnosed another entity, all children suspected of having biliary atresia should undergo operative cholangiography with the intention of proceeding to exploration of the porta hepatis and portoenterostomy as necessary.

Other Causes

Other causes of obstructive jaundice are choledochal cyst, inspissated bile syndrome, and any one of several neonatal hepatitides. A choledochal cyst is identified by the presence of a palpable mass in the right upper quadrant and ultrasonographic confirmation. Inspissated bile syndrome follows a hemolytic process in which a large bilirubin load is excreted into the bile ducts, where it becomes coalesced and impacted, or may occur after a prolonged period of bowel rest with total parenteral nutrition. The syndrome is recognized by abdominal ultrasound. Hepatitis is most commonly of unknown cause. It may be due to a variety of infections, often of maternal origin, such as toxoplasmosis, cytomegalovirus, rubella syndrome, herpes simplex, coxsackievirus, and varicella. Serum should be tested for elevated antibody titers to these agents. Neonatal physiologic jaundice is self-limited and also responds to phototherapy.

Genetic metabolic diseases producing jaundice include α₁-antitrypsin deficiency, galactosemia, and cystic fibrosis. Other rare causes include sepsis, parenteral alimentation cholestasis, Gilbert disease, and Alagille syndrome.

Treatment

Surgical exploration for neonatal jaundice is indicated as early in infancy as possible, when biliary atresia is the likely cause. Delayed treatment will result in progressive cirrhosis. Fluoroscopy should be available in the operating room. The gallbladder is cannulated through a transverse abdominal incision or via laparoscopy. Water-soluble contrast should be gently instilled into the biliary tree. If the image shows a patent common bile duct but no reflux into the liver, a rubber-shod bulldog clamp may be placed on the distal common duct and the cholangiogram repeated. A liver biopsy should be performed in all cases.

Confirmed biliary atresia requires hepatic portoenterostomy (Kasai procedure). The scarred bile ducts and gallbladder are removed, and a Roux-en-Y limb of jejunum is sutured to an area of the hilum bounded laterally by the hepatic artery branches. Some surgeons utilize empiric postoperative antibiotic coverage to prevent cholangitis that can lead to scarring and ongoing occlusion of the bile canaliculi that may remain patent. Steroids have also been used both preoperatively and postoperatively in an effort to prevent ongoing biliary and hepatic fibrosis though outcomes via scientific studies on this topic are equivocal.

Prognosis

A good long-term outcome is related to a meticulously performed procedure, age at operation less than 2 months, absence of cirrhosis at the time of operation, and establishment of adequate bile flow. In general, one-third of the infants will have excellent bile flow and do not develop liver failure; one-third never have bile flow and require early liver transplantation; and one-third have initially good bile flow but months to years later develop progressive biliary cirrhosis requiring liver transplantation. The average life span for infants with uncorrectable biliary atresia without transplantation is 19 months. Death is due to progressive liver failure, bleeding from esophageal varices, or sepsis. For those with established bile flow postoperatively, the most common complication is cholangitis, and this may recur. Most often, the cause is unknown and not readily correctable by surgical means.

CHOLEDOCHAL CYST

A choledochal cyst is a dilation or diverticulum of all or a portion of the common bile duct. Estimates of incidence range from 1:2,000,000 to 1:13,000. There is a female predominance (3:1), and the lesions are more common in Asians, with a large majority of the reported cases from Japan. Numerous theories exist as to the cause of this abnormality, including infectious agents, reflux of pancreatic enzymes into the bile duct via a long common channel, genetic factors, and biliary autonomic dysfunction.

Choledochal cysts are classified into one of five subtypes. Type I is a fusiform dilation of the extrahepatic bile duct. Type II is a saccular outpouching of the common bile duct. Type III is referred to as a choledochocele and is a wide-mouth dilation of the common bile duct at its confluence with the duodenum. Type IV is cystic dilation of both the intrahepatic and extrahepatic bile ducts. Type V consists of lakes of multiple intrahepatic cysts with no extrahepatic component and, when associated with hepatic fibrosis, is termed Caroli disease. Type I and type IV are the most common lesions, with type I cysts accounting for 85% of these abnormalities. Caroli disease appears to be a congenital syndrome and often follows an autosomal recessive pattern of inheritance in association with various other anomalies such as polycystic kidney disease and renal tubular ectasia.

If left untreated, a choledochal cyst may cause cholangitis and cholangiocarcinoma. The risk of cholangiocarcinoma in the first decade of life is only 0.7%; however, this increases to 14% at 20 years and is postulated to increase even further throughout life.

Clinical Findings

The clinical manifestations of a choledochal cyst are recurrent abdominal pain, episodic jaundice, and a right upper quadrant mass, though in most cases one of these features is missing. As children grow older, the cyst may become painful or infected. On rare occasions, children have been described with bile peritonitis secondary to perforation of a cyst. In adults, an abdominal mass is rarely appreciated, and patients present more commonly with symptoms of cholangitis or pancreatitis. Gallstones and cholangitis may develop due to biliary stasis.

The diagnosis is most often established by the clinical presentation and abnormal ultrasonography. Technetium Tc 99m-labeled IDA scan, CT and MRI scans, endoscopic retrograde cholangiopancreatography, and operative cholangiography may be necessary. Ultrasonography is increasingly responsible for detecting choledochal cysts in the fetus.

Treatment

In the past, the cysts were not removed but drained into a limb of intestine. However, many of these patients developed carcinoma in the cyst years later. Presently, the treatment is complete excision with Roux-en-Y hepaticojejunostomy. The duodenal end of the bile duct should be oversewn without injury to the anomalous entry of the pancreatic duct, limiting the amount of residual biliary tissue at risk for malignancy. Side-to-side choledochoduodenostomy is controversial due to a high incidence of reflux bile gastritis. However, it has been used successfully in high volume centers in Asia and is growing in popularity in the United States. Cholecystectomy is always performed. Biliary cirrhosis and portal hypertension, occurring from prolonged ductal obstruction, may be assessed with liver biopsy. The results of choledochal cyst excision with hepaticojejunostomy reconstruction are consistently excellent, but these children do require lifelong follow-up because of the risk of anastomotic stricture and intrahepatic stone formation. There is currently a trend toward laparoscopic approaches to the treatment of choledochal cyst disease.

INGUINAL HERNIA & HYDROCELE

Inguinal hernia is a common condition in infancy and childhood, occurring in 1%-3% of all children. Unlike hernias in adulthood, these nearly always result from a patent processus vaginalis (indirect hernia) and not from a weakness in the floor of the inguinal canal (direct hernia). The processus vaginalis follows the descent of the testis into the inguinal canal. Failure of obliteration of the processus may lead to a variety of anomalies, including hernia, communicating hydrocele, noncommunicating hydrocele, hydrocele of the spermatic cord, and hydrocele of the tunica vaginalis (Figure 43–20).

The processus vaginalis remains patent in over 80% of newborn infants. With increasing age, the incidence of patent processus vaginalis diminishes. At 2 years, 40%-50% are open, and in adults 25% are persistently patent. Actual herniation of bowel into a widely patent processus vaginalis develops in 1%-4% of children; 25% occur within the first year of life. Indirect inguinal hernia occurs four to six times more frequently in males. Direct and femoral hernias occur in children but are very rare.

Hernias are found on the right side in 60% of cases, on the left side in 30%, and bilaterally in 10%. Conditions associated with an increased risk of inguinal hernia include prematurity, family history, history of an abdominal wall defect (eg, gastroschisis), cryptorchidism, intersex anomalies, connective tissue disorders, and ascites. The processus vaginalis may be obliterated at any location proximal to the testis or labium.

Clinical Findings

The incidence of a clinically detectable inguinal hernia varies with gestational age: 9%-11% in preterm infants and 3-5% for full-term infants. The diagnosis of hernia in infants and children can be made only by the demonstration of an inguinal bulge originating from the internal ring. The bulge can be elicited during times of Valsalva (crying, coughing, straining). Having an assistant hold the infant’s arms over his or her head and legs straight will often elicit crying and straining that will aid in the physical examination. Indirect signs, such as a wide external ring and the “silk glove” sign (palpable thickening of the spermatic cord) are not dependable. One must always locate the position of the testis during examination for a hernia since an inguinal bulge due to an undescended or retractile testis may be mistaken for a hernia.

Incarcerated inguinal hernia accounts for approximately 10% of childhood hernias, and the incidence is highest in infants. In the majority of girls with incarcerated hernia, the sac contains the ovary and portion of the tube. These structures are usually a sliding component of the sac. In boys, small bowel, colon, or appendix can be within the sac.

A hydrocele is fluid within the remnant processus vaginalis. It is characteristically an oblong, nontender soft mass. It may be around the testicle only (testicular hydrocele), extend up from the testicle into the inguinal region (inguinoscrotal hydrocele), or be contained within a segment of the processus adjacent to the spermatic cord (hydrocele of the cord) or communicated with the peritoneal cavity (communicating hydrocele). With a noncommunicating hydrocele (the first three hydroceles described above), the processus vaginalis has closed proximally. The normal spermatic cord can usually be palpated above the level of the hydrocele. Transillumination is not reliable in the newborn since intestine and fluid transilluminate equally well. A communicating hydrocele is suspected by a history of size variation (smallest in the morning after sleep, largest during the day after the upright posture or repeated straining).

Differential Diagnosis

A hydrocele under tension may be confused with an incarcerated inguinal hernia. The sudden appearance of fluid confined to the testicular area may represent a noncommunicating hydrocele secondary to torsion of the testis or testicular appendage, epididymo-orchitis, pan-serositis from a recent viral syndrome, or idiopathic scrotal edema. Rectal examination and palpation of the peritoneal side of the inguinal ring may distinguish an incarcerated hernia from a hydrocele or other inguinoscrotal mass, but this is only reliable in the first 2-3 months of age as the internal ring is difficult to reach thereafter.

Complications

The principal risk of not treating an inguinal hernia is incarceration (viscus stuck in sac) and subsequent strangulation (ischemia of said viscus, usually the bowel, not the ovary). Compression of the spermatic vessels by an incarcerated hernia may produce hemorrhagic infarction of the ipsilateral testicle.

Treatment

In general, hydroceles that do not communicate with the peritoneal cavity are physiologic and the vast majority resolve by 18 months of age. Those that persist after 1 year or those that demonstrate changes in size (communicating hydroceles) should be repaired.

Inguinal hernia in infancy and childhood should be repaired; they never resolve spontaneously. In premature infants under constant surveillance in the hospital, hernia repair may be deferred until the baby is ready to be discharged. High ligation of the hernia sac by obliteration of the internal ring (leaving enough space for the spermatic cord) is all that is required. Historically, it was recommended that all boys under 2 years of age and all girls under 5 years undergo operative exploration of the contralateral inguinal canal in search of a clinically silent patent processus vaginalis. This approach has been replaced, in large part, by laparoscopic exploration. This is performed either through the ipsilateral hernia sac, through the umbilicus, or in-line with the internal ring (at the lateral border of the rectus muscle) using a needle scope. If a patent processus vaginalis is demonstrated, a second inguinal incision is made and the procedure is repeated as described above. Recently, a completely laparoscopic repair has been advocated, which has the advantage of simultaneous exploration of the contralateral side and virtually no manipulation of the spermatic cord. The incidence of complications from uncomplicated inguinal hernia repair (recurrence, wound infection, and damage to the spermatic cord) should be 2% or less.

An incarcerated hernia in an infant can usually be reduced initially before operation. This is accomplished by sedation and by elevation of the foot of the bed to keep intra-abdominal pressure from being exerted against the inguinal area. When the infant is well sedated, the hernia may be reduced by gentle constant pressure over the internal ring in a manner that milks the bowel into the abdominal cavity. This is a two-handed maneuver in which one hand “squeezes” the incarcerated mass while the other directs it posteriorly into the internal ring. If the bowel is not reduced within an hour, operation is required. If the hernia is reduced, operative repair should be delayed for 48 hours to allow edema in the tissues to subside. An incarcerated ovary may not be able to be reduced but is usually asymptomatic, and repair at the next available operating room time is sufficient since torsion is rare and the blood supply, unlike that of the intestine, is not compromised by being trapped in the canal. Bloody stools and edema and red discoloration of the skin around the groin suggest a strangulated hernia, and reduction of the bowel should not be attempted. Emergency repair of incarcerated inguinal hernia is technically difficult because the edematous tissues are friable and tear readily. When gangrenous intestine is encountered, the bowel should be resected and an end-to-end intestinal anastomosis performed.

UNDESCENDED TESTIS (CRYPTORCHIDISM)

In the seventh month of gestation, the testicles normally descend into the scrotum. A fibromuscular band—the gubernaculum—extends from the lower pole of the testis to the scrotum, and this band probably acts by guiding the path for descent during differential growth of the fetus rather than by pulling the testes down. Undescended testis (cryptorchidism) is a form of dystopia of the testis that occurs when there is arrested descent and fixation of the position of the testis retroperitoneally, in the inguinal canal, or just beyond the external ring. Continued descent of the testes may progress after birth, but descent comes to a halt before 2 years of age.

Another form of dystopia is ectopic testis, in which the gubernaculum may have guided the testis near the pubis, penis, perineum, or medial thigh or to a subcutaneous position superficial to the inguinal canal. In these instances, the testis has descended beyond the external ring of the inguinal canal, and the vascular supply is sufficiently developed so as to pose little difficulty in operative repair.

Normal spermatogenesis requires the cooler temperature range provided in the scrotum. When the testis remains undescended and subjected to normal body temperature, degenerative changes in the seminiferous tubules occur in which the lining cells become progressively atrophic and hyalinized, with peritubular fibrosis. The degenerative changes begin to occur at 2 years of age. Unless the disorder is corrected, all bilaterally cryptorchid adult males become sterile.

The incidence of undescended or partially descended testis is 1%-2% in full-term infants and up to 30% in premature babies. The right testis is affected in 45% of cases, the left testis in 30%, and both testes in 25%. A patent processus vaginalis is present in 95% of patients with cryptorchidism, and approximately 25% develop a clinical hernia.

Anomalies associated with cryptorchidism occur in about 15% of cases and include a wide variety of syndromes such as Klinefelter syndrome, hypogonadotropic hypogonadism, the prune belly syndrome, horseshoe kidneys, renal agenesis or hypoplasia, exstrophy of the bladder, ureteral reflux, gastroschisis, and cloacal exstrophy.

Clinical Findings

Physical examination demonstrates an “empty hemiscrotum” with absent rugae. Cryptorchidism must be differentiated from a retractile testis. Because of the very active cremaster of children under 3 years of age and the small size of the testis, the gonad can retract into the external inguinal ring or within the inguinal canal—this is called a retractile testis—and it is a variant of normal. The retractile testis can be manually manipulated into the mid to lower scrotum and no therapy is required.

Treatment

Operation is indicated after 12-18 months since degenerative changes begin to take place in these testes that may impair spermatogenesis and lead to malignant transformation. Additionally, cryptorchid testes are more susceptible to trauma and torsion, often have an associated inguinal hernia, and may cause adverse psychosocial effects. The incidence of testicular cancer in a cryptorchid testis is 30 times higher than in the normal population and is not lessened by repair. The role of repair is to allow reliable examination for a testicular mass later in life.

Orchidopexy is the surgical method for mobilizing the testis—based on the testicular vessels and the vas deferens—from its ectopic location into the scrotum. When the dystopic testis is not palpable preoperatively, 17% are absent, 33% are intra-abdominal, and 50% are in the inguinal canal or just beyond the inguinal ring. If the testis is not palpable when the child is anesthetized, laparoscopy should be performed before making an inguinal incision. Increasingly, the complete operation (diagnosis and intra-abdominal mobilization) is performed laparoscopically. This will allow for identification of an abdominal testis or the diagnosis of an absent testis (usually due to in utero torsion). Very high testes with a short blood supply can be brought into the scrotum by a two-stage repair (dividing the spermatic artery and vein with clips or laser followed by positioning in the scrotum 6-8 weeks later) based on collateral blood supply via the vas deferens and the gubernaculum. Testes confined in the inguinal canal (25% of cases) can usually be brought into the scrotum in one stage. Ectopic testicles located outside the inguinal canal, such as in the subcutaneous inguinal pouch, occur in over 50% of cases, and the testicular vessels are so well developed that scrotal placement is rarely a problem. The prognosis for fertility following orchidopexy in unilateral maldescent is 80%, whereas fertility after bilateral orchidopexy is about 50%. Due to variable degrees of tension and tenuous blood supply, the testis after an orchidopexy is often smaller than the contralateral one.

TESTICULAR TORSION

Testicular torsion is most frequent in late childhood and early adolescence, though the range can include the fetus and the adult. Anatomically, there are two forms of testicular torsion depending on where the spermatic cord is twisted with respect to the tunica vaginalis: intravaginal torsion (bell-clapper deformity), the most common form, and extravaginal torsion that occurs principally in neonates and in children with an undescended testis. Rarely, the testis may twist on a long epididymal mesentery. In children and adolescents, testicular torsion is either idiopathic or occurs after activity or trauma.

Clinical Findings

Acute scrotal or testicular pain that may radiate to the lower abdomen is usually present. Progressive swelling, edema, and erythema of the hemiscrotum occur. The testis is exquisitely tender to palpation. The testicle may be foreshortened, the epididymis may lie anteriorly, and the cremasteric reflex may be absent—though these signs are difficult to elicit. Fetal or neonatal torsion is probably responsible for the “absent” testis noted during laparoscopy.

The diagnosis of testicular torsion is based mainly on clinical examination. Although one may utilize Doppler ultrasonography and radionuclide scanning to aid in the diagnosis, these tests are time consuming and, in the case of ultrasound, operator specific.

Differential Diagnosis

Torsion of the testicular appendices (vestigial müllerian duct structures) and epididymitis may mimic testicular torsion. With epididymitis, there is often pyuria, voiding symptoms, and fever. Torsion of the testicular appendices often has a gradual onset, and careful palpation may reveal point tenderness rather than diffuse tenderness. There may be a visible necrotic lesion on scrotal transillumination (blue dot sign).

Treatment

If the diagnosis is strongly suspected, the best “test” is operative scrotal exploration. The testicular salvage rate if detorsion is performed within 6 hours after onset of symptoms is up to 97%, versus less than 10% if delayed more than 24 hours. At operation, the torsion is corrected and the gonad, if viable, is fixed to the hemiscrotum in three places. Because the paired testicle is at risk for torsion since the testicular anatomy tends to mirror itself, contralateral orchiopexy (suture fixation) should be performed in all cases. Torsion of the testicular appendices tends to be self-limiting since necrosis and autoamputation usually occur. Treatment is with warm baths, limited activity, and an anti-inflammatory agent. If significant pain persists after 2-3 days and the appendix has not autoamputated, excision is indicated. Testicular salvage after neonatal testicular torsion is very rare.

UMBILICAL HERNIA

A fascial defect at the umbilicus is frequently present in the newborn, particularly in premature infants. The incidence is highest in African-American children. In most children, the umbilical ring progressively diminishes in size and eventually closes. Fascial defects less than 1 cm in diameter close spontaneously by 5 years of age in 95% of cases. When the fascial defect is greater than 1.5 cm in diameter, it seldom closes spontaneously. Unlike inguinal hernias, protrusion of bowel through the umbilical defect rarely results in incarceration in childhood. Surgical repair is indicated if the intestine becomes incarcerated, when the fascial defect is greater than 1.5 cm, and in all children over 4 years of age. Both open and laparoscopic approaches are associated with uniformly excellent results.

OMPHALOCELE

This is a midline abdominal wall defect noted in 1:5000 live births. The abdominal viscera (commonly liver and bowel) are contained within a sac composed of peritoneum and amnion from which the umbilical cord arises at the apex and center (Figure 43–21). When the defect is less than 4 cm, it is termed as hernia of the umbilical cord; when greater than 10 cm, it is termed a giant omphalocele. Associated abnormalities occur in 30%-70% of infants and include, in descending order of frequency, chromosomal abnormalities (trisomy 13, 18, 21), congenital heart disease (tetralogy of Fallot, atrial septal defect), Beckwith-Wiedemann syndrome (large-for-gestational-age baby; hyperinsulinism; visceromegaly of kidneys, adrenal glands, and pancreas; macroglossia, hepatorenal tumors, cloacal extrophy), pentalogy of Cantrell, and prune belly syndrome (absent abdominal wall muscles, genitourinary abnormalities, cryptorchidism). Small omphaloceles are most often linked to chromosomal defects and Beckwith-Wiedemann syndrome, especially when the liver is not in the hernia sac.

Treatment

The primary goal of surgery is to return the viscera to the abdominal cavity and close the defect. With an intact sac, emergency operation is not necessary, so a thorough physical examination and workup for associated anomalies is performed. An orogastric tube should be placed on suction to minimize intestinal distention.

The success of primary closure depends on the size of the defect and of the abdominal and thoracic cavities as well as the presence of associated problems (eg, lung disease). It is wise to leave the sac in situ since primary closure may not be possible, and in this way one has maintained the best biologic dressing for the viscera. Supplemental coverage with plastic wrap or a bowel bag can be used to prevent heat loss. If the viscera reduce but abdominal wall closure is not possible, there are three options: staged repair, prosthetic patch repair, or delayed operative management with initial epithelialization and compression for gradual return of domain. A staged repair aims to create a protective extra-abdominal extension of the peritoneal cavity (termed a silo), allowing gradual reduction of the viscera and gradual abdominal wall expansion using two parallel sheets of reinforced Silastic sheeting sutured to the fascial edges or a preformed one-piece silo with a collapsible ring at its base for ease of insertion. A prosthetic patch repair bridges the fascial gap with a synthetic material (eg, polytetrafluoroethylene) and the skin is closed over the patch. The silo is progressively compressed to invert the amniotic sac and its contents into the abdomen and to bring the edges of the linea alba together by stretching the abdominal wall muscles. This usually requires 5-7 days, after which the defect is then primarily closed. The intra-abdominal pressure produced by the silo should not exceed 20 cm H₂O to avoid impairing venous return from the bowel and kidneys. When abdominal relaxation is sufficient to allow the rectus muscles to come together, the silo is removed, the amnion is left inverted into the abdominal cavity, and the defect is closed.

Delayed operative management is appropriate for infants with severe associated anomalies or a giant omphalocele. The amnion is allowed to dry and form an eschar. The membrane becomes vascularized beneath the eschar, and contraction of the wound with skin growth covers the defect. This can be further facilitated by creation of a compression orthotic that allows for the gradual return of abdominal contents and recreation of abdominal domain. A ventral hernia results, which is repaired electively when the patient is stable. The survival rate for infants with small omphaloceles is excellent. Deaths associated with larger omphaloceles are principally from wound dehiscence with subsequent and ensuing infection or from associated anomalies.

GASTROSCHISIS

Gastroschisis is a defect in the abdominal wall that usually occurs to the right of a normal insertion of the umbilical cord (Figure 43–22). It is believed to arise at the site of involution of the right umbilical vein, though a less popular theory holds there is some evidence that it results from rupture of an omphalocele sac in utero. It is twice as common as omphalocele and the defect is usually smaller. The remnants of the amnion are usually reabsorbed. The skin may continue to grow over the remnants of the amnion, and there may be a bridge of skin between the defect and the cord. The small and large bowel, stomach, and often the fallopian tube/ovary/testis herniate through the abdominal wall defect. Unlike an omphalocele, the liver is virtually never present in the defect. Having been bathed in the amniotic fluid and with compression of the mesenteric blood supply at the abdominal defect, the bowel wall is edematous and has a very thick, shaggy membrane (“peel”) covering it. The loops of intestine are usually matted together, and the intestine appears to be abnormally short.

Complications

Since the bowel has not been contained intra-abdominally, the abdominal cavity fails to enlarge, and it frequently cannot accommodate the protuberant bowel. Over 70% of infants with this disorder are premature, but associated anomalies occur in fewer than 10% of cases. Nonrotation of the midgut is present. Associated intestinal atresia occurs in approximately 7% because segments of intestine that have herniated through the defect become infarcted in utero.

Treatment & Prognosis

Unlike omphalocele, urgent repair is necessary. Small defects may be closed primarily after manually stretching the abdominal cavity. A staged approach is frequently required using a silo as described above (under Omphalocele). As bowel wall edema subsides, the bowel will readily reduce into the abdominal cavity. Reduction is aided by having the infant paralyzed and receiving endotracheal ventilation to relax the abdominal wall and allow it to stretch and accommodate the bowel. When the bowel has been completely reduced (usually 5-7 days), the silo is removed and the abdominal wall is closed. Recently, the use of the umbilical remnant or a patch dressing has been described to allow primary closure without the need for operative intervention.

The death rate for infants with gastroschisis is less than 5%. Poor GI function and episodes of sepsis, presumably from compromised bowel, may occur. Prolonged postoperative ileus (> 2 weeks) is the rule, and total parenteral nutrition is necessary. Primary repair of an associated intestinal atresia is rarely safe and possible. Either a proximal stoma is created or the atretic ends are reduced and repaired 6 weeks later when the intra-abdominal inflammation has subsided.

Cutaneous vascular anomalies comprise a group of congenital and acquired vascular malformations of the skin. They are present in 2.6% of all newborns. These anomalies are broadly divided into two categories: hemangiomas and vascular malformations. They are most precisely classified by the biologic activity of the endothelium.

HEMANGIOMAS

Hemangiomas demonstrate endothelial hyperplasia and are seen in children and adults but behave differently at different ages. Hemangiomas are much more common than vascular malformations. In the neonatal period, hemangiomas can be subclassified according to their growth phase. A rapid proliferating phase is usually seen during the first few years of life followed by an involuting phase that may last several years.

Clinical Findings

The clinical appearance depends on the depth of the lesion. Superficial dermal lesions (capillary hemangiomas, strawberry hemangiomas) are raised and profoundly erythematous, with an irregular texture; deep lesions (cavernous hemangiomas) are smooth and slightly raised, with a bluish hue or a faint telangiectatic pattern on the overlying skin. Mixed lesions are often noted (capillary-cavernous hemangiomas). Twenty percent of patients have multiple lesions. Complications from hemangiomas consist of ulceration (during the proliferative phase), bleeding, thrombocytopenia (Kasabach-Merritt syndrome), consumptive coagulopathy, high-output heart failure, visual field encroachment, airway obstruction, and minor skeletal distortions.

Treatment

Fifty percent of hemangiomas will involute without treatment by age 5 years and 70% by 7 years. The remainder will slowly resolve by age 10-12 years. Steroid therapy hastens the rate of proliferation of hemangiomas by 30%-90% and is indicated for complicated lesions (ie, those causing severe physiologic or anatomic abnormalities).

CUTANEOUS VASCULAR MALFORMATIONS

Vascular malformations, in contrast to hemangiomas, have normal endothelial cell turnover and tend to grow proportionally with the child. These lesions are structural anomalies that are considered errors in vascular morphogenesis. They are usually visible at birth but may take years or even decades to become manifest. They are separated into low-flow and high-flow variants and further classified according to the type of vascular channel abnormality: capillary, venous, arterial, and mixed malformations. Capillary and venous malformations are low-flow variants; arterial and mixed arterial and venous ones are high-flow variants.

Capillary Malformations

Capillary malformations are nevus flammeus (port-wine stain), nevus flammeus neonatorum (angel kiss), nevus flammeus nuchae (stork bite, salmon patch), angiokeratomas, and telangiectasias (spider, hereditary hemorrhagic telangiectasia [Rendu-Osler-Weber syndrome]). They are prone to infection and are treated aggressively with intravenous antibiotics. A compression garment should be used if anatomically feasible. Some lesions can be excised or injected with a sclerosing solution.

Venous Malformations

Venous malformations have a wide spectrum of appearances ranging from simple varicosities to complex lesions that may be located in deeper tissues (eg, bone, muscle, salivary gland). Pain is often related to thrombosis within the lesion. Radiographic imaging delineates the nature and extent of the lesion (angiogram, CT, MRI). Photocoagulation or Nd:YAG laser may be effective for superficial lesions. Resection is the definitive treatment since it can reduce bulk, improve contour and function, and control pain. It is limited by anatomic boundaries, and multiple, staged procedures may be required.

Arterial Malformations

Arterial and arteriovenous malformations are associated with multiple small fistulas surrounded by abnormal tissues and can cause high-output cardiac failure. They are most common in the head and neck region (especially intracerebral). There is pain and overlying cutaneous necrosis. Adjacent osseous structures are often destroyed. Selective embolization is used either as palliation or presurgically to limit hemorrhage. Excision, when possible, is the treatment of choice.

Combined Malformations

Combined vascular malformations and hypertrophy syndromes consist of Klippel-Trenaunay-Weber syndrome (combined capillary-lymphatic venous malformation associated with lower limb hypertrophy), Parkes-Weber syndrome (upper limb arteriovenous shunting), Maffucci syndrome (low-flow vascular malformations and multiple extremity enchondromas with hypoplastic long bones), and Sturge-Weber syndrome (upper facial port-wine stain and vascular anomalies of the choroid plexus and leptomeninges).

NEUROBLASTOMA

Of all childhood neoplasms, neuroblastoma is exceeded in frequency only by leukemia and brain tumors. Approximately 60% of cases occur within the first 2 years of life and 97% within the first 20 years. This tumor is of neural crest origin and may originate anywhere along the distribution of the sympathetic chain. The most common site for primary disease is in the abdomen (adrenal), followed by the thorax, pelvis, and occasionally the head and neck. Neuroblastomas originate in the retroperitoneal area in 75% of cases; 55% arise from the adrenal gland. They may reach massive size and violate tissue planes such that they envelop major blood vessels, their branches, and other important structures (eg, ureters), making initial primary resection potentially hazardous. The biologic behavior varies with the age of the patient, the site of primary origin, and the extent of the disease.

Clinical Findings

A. Symptoms and Signs

Symptoms are site specific. The most common symptom is pain (from primary or metastatic disease). Nonspecific symptoms include growth retardation, malaise, fever, weight loss, and anorexia. Children frequently appear ill at the time of diagnosis. Constipation and urinary retention are signs of pelvic disease. Orbital metastases commonly present with periorbital ecchymoses and proptosis (“raccoon eyes”). Spinal canal involvement may present with acute paralysis due to compression. Opsomyoclonus syndrome is an acute cerebellar encephalopathy characterized by ataxia, opsoclonus (“dancing eyes”), myoclonus, and dementia. It occurs in association with approximately 3% of all neuroblastomas and is usually associated with a good prognosis, though the neurologic abnormalities tend to persist after successful treatment of the primary tumor. Interestingly, it is not due to CNS metastases of neuroblastoma and is believed to be immune mediated. Infants with stage IV-S disease (see below) may display cutaneous metastases (“blueberry muffin” lesions) or respiratory embarrassment secondary to massive hepatomegaly from tumor infiltration. Palpable lesions are often hard and fixed.

In infants, metastases confined to the liver or subcutaneous fat are frequent and cortical bone metastases unusual. In older children, metastases to lymph nodes and bone are found in over 70% of cases at diagnosis. Pain in areas of bony involvement and in joints with associated myalgia and fever mimics rheumatic fever. Eighty-five to 90% secrete high levels of the catecholamine metabolites vanillylmandelic acid and homovanillic acid. Hypertension and diarrhea may occur as a result of catecholamine and vasoactive intestinal peptide secretion.

B. Imaging Studies

Imaging is aimed at defining the extent of the tumor and determining the presence of metastases to distant sites (most commonly lymph nodes, bone, lung, and liver). Neuroblastoma is the most common abdominal tumor to demonstrate calcifications (50%) prior to chemotherapy. CT scan of the area of tumor involvement helps to identify the relationship to surrounding structures and determine resectability. MRI is useful in assessing tumor within the spinal canal and spinal cord compression. MRI is as sensitive as CT scanning in terms of assessing tumor size and resectability but has the added advantage of being superior to CT in assessing vessel encasement, vessel patency, and spinal cord compression. MRI can also demonstrate bone marrow involvement in selected cases. Metaiodobenzylguanidine (MIBG) scintigraphy is very sensitive in detecting tumors that concentrate catecholamines and has been useful in the diagnosis of primary, residual, and metastatic disease in patients with neuroblastoma. For retroperitoneal tumors, an intravenous urogram may show displacement or compression of the adjacent kidney without distortion of the renal calices. Bone scans may be useful in detecting osseous metastases.

Prognostic Factors

Favorable prognostic factors include diagnosis before age 18 months, a thoracic primary lesion, and low stage. In addition, several molecular and cellular characteristics of neuroblastic tumors are prognostically important. The most important is the high incidence of amplification of the proto-oncogene N-myc, seen in approximately 30% of tumors. Amplification of N-myc (> 10 copies) adversely correlates with prognosis independently of clinical stage. Using the histologic Shimada index, well-differentiated, stroma-rich tumors have a favorable prognosis. An elevated ratio of vanillylmandelic acid to homovanillic acid correlates with an improved outcome in patients with advanced disease. Other biochemical indicators of advanced disease include neuron-specific enolase, serum ferritin, and serum lactate dehydrogenase. Staging systems are surgically and anatomically based and have prognostic value. The most recent is the International Neuroblastoma Staging System (Table 43–6). Stage IV-s has favorable outcomes to older children with stage III and IV disease.

Treatment

Diagnosis depends upon demonstration of immature neuroblastic tissue obtained by tissue or bone marrow aspirate and biopsy. Tissue is obtained by biopsy (either by laparotomy or laparoscopically), which allows accurate determination of resectability and ensures that adequate tissue (1 g or 1 cm³) is available for determination of tumor markers, cytologic studies, and the special stains required for accurate diagnosis and staging.

The spectrum of treatment for neuroblastoma is driven by risk stratification based on multiple factors beyond Stage. A localized neuroblastoma should be excised, and the local area of the tumor should be irradiated only when gross tumor remains. Unresectable neuroblastomas should be biopsied and treated initially by chemotherapy and radiation therapy and then by surgical resection for residual tumor. Removal of all residual disease is the goal. Most neuroblastomas are radiosensitive and respond to radiation. Patients with disseminated disease should be treated with a combination of chemotherapeutic agents such as cyclophosphamide, vincristine, dacarbazine, doxorubicin, cisplatin, and teniposide. Patients with stage III or stage IV tumors who are at high risk by virtue of their age or of the stage and biologic characteristics of the tumor benefit from total body irradiation followed by either allogeneic or, more commonly, autologous bone marrow transplantation.

WILMS TUMOR (NEPHROBLASTOMA)

Renal neoplasms account for about 10% of malignant tumors in children. Nephroblastoma (Wilms tumor), which accounts for 80% of these, consists of a variety of embryonic tissues such as abortive tubules and glomeruli, smooth and skeletal muscle fibers, spindle cells, cartilage, and bone. Seventy-five percent of children with nephroblastoma are under 5 years of age; the peak incidence is at 2-3 years. With current multimodality treatment, the survival rate exceeds 85%.

The left kidney is affected in 50% of cases of Wilms tumor and the right kidney in 45%. In 5% of cases, the tumors are bilateral; 60% are synchronous and 40% are metachronous. Associated anomalies and their incidence per 1000 cases are aniridia, 8.5; hypospadias, 18; hemihypertrophy, 25; and cryptorchidism, 28. Beckwith-Wiedemann syndrome and neurofibromatosis occur together occasionally, and renal tumors may also occur in families. The constellation of Wilms tumor, aniridia, genitourinary anomalies, and mental retardation (WAGR syndrome) is associated with deletion of 11p13.

Clinical Findings

A. Symptoms and Signs

In contrast to those with neuroblastoma, children are usually healthy appearing. Symptoms consist of abdominal enlargement in 60%; pain in 20%; hematuria in 15%; malaise, weakness, anorexia, and weight loss in 10%; and fever in 3%. Hypertension is noted in over half of patients. An abdominal mass, palpable in almost all cases, is usually very large, firm, and smooth, and it does not ordinarily extend across the midline.

B. Imaging Studies

Imaging is required to determine the extent of the mass; to assess for bilateral disease, venous invasion, and metastases; and to confirm contralateral renal function. This is accomplished with abdominal ultrasound (to assess venous invasion) and a CT scan of the chest and abdomen.

Differential Diagnosis

Abdominal masses may also be caused by hydronephrotic, multicystic, or duplicated kidneys and by neuroblastoma, teratoma, hepatoma, and rhabdomyosarcoma. Ultrasonography and CT scanning can usually distinguish nephroblastoma from these other tumors. Calcification occurs in 10% of cases of nephroblastoma and tends to be more crescent-shaped, discrete, and peripherally situated than the calcifications of neuroblastoma, which are finely stippled.

Treatment & Prognosis

Surgical excision is often accomplished without any preoperative treatment unless significant inferior vena caval thrombus is present. The aim of surgery is to completely remove the tumor (nephrectomy) and ureter without spill and to determine the tumor stage by virtue of its extent and the presence of lymph node involvement (Table 43–7). Stage I is tumor confined to a kidney that has been completely excised; stage II is tumor extending beyond the kidney (perirenal tissues, renal vein or vena cava, biopsy or local spill in the flank) and completely excised; stage III is residual, nonhematogenous tumor confined to the abdomen (lymph node metastases, preoperative or intraoperative diffuse peritoneal deposits, residual tumor at the surgical margins, or unresectable tumor); stage IV is hematogenous metastases (lung, liver, bone, and brain); and stage V is bilateral renal involvement.

Irradiation of the tumor bed is indicated if the tumor has extended beyond the capsule of the kidney to involve adjacent organs or lymph nodes or if intraoperative tumor spillage has occurred. Very large tumors may be treated with radiation therapy and chemotherapy preoperatively to reduce their size. A significant reduction in size usually occurs in 7-10 days, after which nephrectomy can be readily performed. Nephrectomy is accomplished through a long transverse or thoracoabdominal incision.

Palpation of the renal veins and inferior vena cava is performed to detect tumor thrombus. Bilateral disease (6%) mandates “nephron-sparing” surgery. The treatment of bilateral disease is individualized with the goal of eradicating tumor while preserving the maximal amount of functional renal mass. It is a contraindication to primary nephrectomy. Suspicious lesions in the opposite kidney are biopsied. If the tumor is too large for safe resection, it is biopsied along with regional lymph nodes. Chemotherapy with or without radiation therapy will usually result in a significant reduction in tumor size and allow subsequent resection. Metastatic foci in the lung or liver may be resected or treated with radiation therapy. Any residual tumor following radiation therapy, including multiple lesions, should be resected.

Overall survival is 85%, and most patients are cured. Survival correlates with stage and histology. The 4-year survival with respect to stage and histology is shown in Table 43–8. Tumor rupture with gross spillage portends a sixfold increase in risk of local recurrence and requires the use of postoperative external beam radiation.

RHABDOMYOSCARCOMA

Rhabdomyosarcoma is a childhood malignancy that arises from embryonic mesenchyme with the potential to differentiate into skeletal muscle. It is the most common pediatric soft tissue sarcoma and is the third most common solid malignancy. It accounts for 4%-8% of all malignancies and 5%-15% of all solid malignancies of childhood.

The age distribution is bimodal, the first peak is between 2 and 5 years, and the second peak is between 15 and 19 years. Fifty percent present before 5 years, and 6% present in infancy. There is an increased incidence in patients with neurofibromatosis, Beckwith-Wiedemann syndrome, and Li-Fraumeni cancer-family syndrome.

Rhabdomyosarcoma is divided into distinct histologic groups: favorable, intermediate, and unfavorable. Favorable types (5%) include the sarcoma botryoides and spindle cell variants. Botryoid tumors typically present in young children from within visceral cavities (eg, vagina), while spindle cell types have a predilection for paratesticular sites. Intermediate-prognosis tumors (50%) are of the embryonal type. Unfavorable-prognosis tumors (20%) include alveolar and undifferentiated tumors. Alveolar tumors arise from the extremities, trunk, and perineum. Undifferentiated tumors arise from the extremity and head and neck sites. Thirteen percent cannot be adequately characterized and are labeled “small, round cell sarcoma, type indeterminate.”

Clinical Findings

The clinical presentation varies with the site of origin of the primary tumor, the patient’s age, and the presence or absence of metastatic disease. The majority of symptoms are secondary to the effects of compression by the tumor or by the presence of a mass. The most common site is the head and neck region (35%). These are subdivided into orbital (10%), parameningeal (15%), and nonparameningeal (10%) sites. They are usually embryonal and present as asymptomatic masses or functional deficits. Genitourinary rhabdomyosarcoma (26%) are divided into two groups: bladder and prostate (10%) and nonbladder and prostate, including paratesticular sites, perineum, vulva, vagina, and uterus (16%). The most common histologic type is embryonal, though botryoid tumors and spindle cell tumors are seen more frequently here than in any other site. These tumors may be so massive as to make determination of the primary tumor site impossible. There is a propensity for early lymphatic spread in genitourinary primary tumors. Bladder and prostate tumors frequently present with urinary retention or hematuria, while vaginal and uterine tumors present with vaginal bleeding or discharge or with a mass exiting the vagina. Extremity rhabdomyosarcoma (1%) are more common in the lower than in the upper extremity. These are usually alveolar varieties with a high incidence of regional nodal involvement and distal metastases. “Other” sites account for 20%. The most common are the thorax, diaphragm, abdominal and pelvic walls, and intra-abdominal or intrapelvic organs.

Staging is determined by the histologic variant, the primary site, and the extent of disease since each has an important influence on the choice of treatment and on prognosis. CT scanning or MRI is essential to evaluate the primary tumor and its relationship to surrounding structures. A clinical grouping system was designed by the Intergroup Rhabdomyosarcoma Study Group to stratify different extents of disease in order to compare treatment and outcome results (Table 43–9). It is based on pretreatment and operative outcome and does not account for the biologic differences or the natural history of tumors arising from different primary sites.

Treatment & Prognosis

The surgical management is site specific and includes complete wide excision of the primary tumor and surrounding uninvolved tissue while preserving cosmetic appearance and function. Incomplete excision (beyond biopsy) or tumor debulking is not beneficial, and severely mutilating or debilitating procedures should not be performed. Tumors not amenable to primary excision should be amply biopsied and then treated with neoadjuvant agents; secondary excision is then performed and is associated with a better outcome than partial or incomplete excisions. Clinically suspicious lymph nodes should be excised or biopsied, while excision of clinically uninvolved nodes is site specific. Primary reexcision has been shown to improve outcome in patients where microscopic margins are positive, where the initial procedure was not a formal “cancer” resection, or where malignancy was not suspected preoperatively.

The 5-year survival for stage I tumors is 90%; for stage II, clinical group I or II, it is 77%; for stage II, clinical group III, it is 65%; and for stage III lesions (group I, II, or III), it is 55%. Stage IV tumors arising from favorable sites of origin are curable, while those from unfavorable sites have a very poor prognosis. The prognosis for recurrent disease is poor.

TERATOMA

Teratomas are embryonal neoplasms derived from pluripotent cells containing tissue from at least two of three germ layers (ectoderm, endoderm, mesoderm). Approximately 80% are found in females. They are typically midline or para-axial tumors and are distributed in the following regions: sacrococcygeal (57%), gonadal (29%), mediastinal (7%), retroperitoneal (4%), cervical (3%), and intracranial (3%). Other sites are rare. Nongonadal teratomas present in infancy; gonadal ones, in adolescence. Twenty-one percent are malignant.

The serum alpha-fetoprotein (AFP) level is elevated in tumors containing malignant endodermal sinus (yolk sac) elements. Serial AFP levels are markers for recurrence. Beta-human chorionic gonadotropin (β-hCG) is produced from those containing malignant choriocarcinoma tissue. Rarely, enough β-hCG is produced to cause precocious puberty. Elevated AFP and β-hCG levels in histologically benign tumors indicate an increased risk of recurrence and malignant transformation, particularly with “immature” benign teratomas.

Sacrococcygeal Teratoma

The majority of sacrococcygeal teratomas present in the newborn period and can be detected by prenatal ultrasound. Females predominate; a history of twins is common. Pregnancy may be complicated by fetal high-output cardiac failure via arteriovenous shunting within the tumor, maternal polyhydramnios, and hydrops fetalis leading to fetal demise. Fetal surgery has been utilized successfully in those with hydrops. The tumors are classified according to location: type I, predominantly external (46%); type II, external mass and presacral component (35%); type III, visible externally, but predominantly presacral (9%); and type IV, entirely presacral, not visible externally (10%).

Treatment is excision of the tumor and coccyx; type I and II lesions are resected from the perineal approach, and type III and IV lesions require a combined intra-abdominal and perineal resection. The majority (97%) of newborn sacrococcygeal teratomas are benign and do not require adjuvant therapy. Follow-up requires serial AFP levels and physical examinations, including digital rectal examination. Recurrent tumors are excised. The greatest risk factor for malignancy is age at diagnosis. The malignancy rate is approximately 50%-60% after 2 months of age. Malignant tumors are often treated with surgery and chemotherapy. The 5-year survival for malignant germ cell tumors arising from a sacrococcygeal teratoma is approximately 50%.

Mediastinal Teratoma

Mediastinal teratomas account for approximately 20% of all pediatric mediastinal tumors. They usually arise in the anterior mediastinum, though intrapericardial and cardiac lesions have been reported. Symptoms include respiratory distress, chronic cough, chest pain, and wheezing. Males with β-hCG-producing tumors may display precocious puberty. Cardiac failure may develop from compression or pericardial effusion. The chest radiograph demonstrates a calcified anterior mediastinal mass in over one-third of cases. Ultrasonography delineates cystic and solid components. General anesthesia should not be induced until a CT scan evaluation of the airway has been obtained since the supine position coupled with a loss of airway tone from anesthetic agents may allow the anterior mass to obstruct the distal trachea, making rapid establishment of an airway all but impossible. If significant airway compression is present, an awake needle biopsy under local anesthesia followed by radiation therapy or chemotherapy is indicated. Complete resection is definitive treatment.

Cervical Teratoma

Cervical teratomas are rare neonatal neck masses that by virtue of their large size frequently cause respiratory distress. Calcifications may be seen on a plain radiograph and a mixed cystic and solid appearance on ultrasound. These tumors are most commonly benign. The most common malignant type is the yolk sac tumor (endodermal sinus tumor). Serum AFP and β-hCG levels can be monitored to detect the presence of recurrent germ cell tumors. The rapid establishment of an endotracheal airway may be necessary. Tracheostomy is hazardous because of the distortion of landmarks by the large mass. Treatment is complete excision. Some malignant tumors respond to radiation therapy. Regardless of the stage of disease, these tumors behave aggressively and should be treated adjunctively with a combination of cisplatin, vinblastine, and bleomycin or with dactinomycin, cyclophosphamide, and vincristine.

LIVER NEOPLASMS

Tumors of the liver are uncommon in childhood (2% of all pediatric malignancies). More than 70% of pediatric liver masses are malignant. The majority of hepatic malignancies are of epithelial origin, while most benign lesions are vascular in nature.

1. Hepatoblastoma

Hepatoblastomas account for nearly 50% of all liver masses in children and approximately two-thirds of malignant tumors. The majority are seen in children under 4 years of age, and two-thirds are noted prior to 2 years of age. Beckwith-Wiedemann syndrome, hemihypertrophy, familial adenomatous polyposis syndrome, fetal alcohol syndrome, and parenteral nutrition administration in infancy all increase the risk of hepatoblastoma.

Clinical Findings

A. Symptoms and Signs

The most common finding is an asymptomatic abdominal mass or diffuse abdominal swelling in a healthy-appearing child. There may be obstructive GI symptoms secondary to compression of the stomach or duodenum or acute pain secondary to hemorrhage into the tumor. Physical examination reveals a nontender, firm mass in the right upper quadrant or midline that moves with respiration. Advanced tumors present with weight loss, ascites, and failure to thrive. Approximately 10% of males present with isosexual precocity secondary to tumor secretion of β-hCG.

B. Laboratory Findings

Laboratory studies reveal nonspecifically elevated liver function tests and a mild anemia. Thrombocytosis of unknown cause is occasionally seen. AFP is significantly elevated in 90-95%. This marker is also associated with other malignant lesions such as germ cell tumors, but levels are lower. Serial serum AFP measurements are used to monitor patients for tumor recurrence. Levels fall to normal after curative resection.

C. Imaging Studies

Abdominal ultrasound demonstrates a solid, usually unilobar (right lobe most common) lesion of the liver but lacks sufficient detail to determine resectability. Abdominal CT scan using intravenous contrast is currently the imaging procedure of choice both for diagnosis and for planning therapy. The CT scan demonstrates the tumor’s proximity to major vascular and hilar structures. The typical CT appearance is a solid solitary mass with lower attenuation levels than those of the surrounding liver. A novel technique, CT arterioportography, holds promise as a reliable means of assessing vascular invasion along with gross tumor distribution. MRI has proved to be very useful in defining the patency of vascular structures.

Differential Diagnosis

One major management problem is the inability to differentiate adenomas from hepatocellular carcinoma. Because of this, hepatic adenoma, despite being a benign lesion, is often excised. Focal nodular hyperplasia is a well-circumscribed, nonencapsulated nodular liver mass. Ultrasonography and CT scan demonstrate a solid mass, but one cannot differentiate it from adenoma or malignancy without a biopsy. If the diagnosis can be made by biopsy (percutaneous or open), no further treatment is needed. Mesenchymal hamartoma is an uncommon benign lesion presenting in the first year of life as an asymptomatic large solitary mass usually confined to the right lobe of the liver. CT scan demonstrates a well-defined tumor margin and minimal to no contrast enhancement. The treatment is surgical wedge resection; lobectomy is rarely required.

Treatment

The definitive diagnosis of hepatoblastoma requires tissue biopsy. Although this can be performed percutaneously, there are reports of “seeding” of the biopsy tract. It is preferable to perform open biopsy of the lesion with assessment of resectability. If the lesion is not primarily resectable, vascular access is obtained during the same anesthetic interval for subsequent chemotherapy. Table 43–10 outlines the surgical staging system for childhood hepatic malignancies.

Complete surgical resection is the major objective of therapy and represents the only chance for cure. Approximately 60% of patients will have primarily resectable lesions. Lobectomy or extended lobectomy (trisegmentectomy) is usual, but segmental (nonanatomic) resection of small isolated tumors may be possible. Careful preoperative evaluation and planning have made liver resection in children a safe procedure, with a mortality rate of less than 5%. Adequate exposure can be obtained via an extended subcostal or bilateral subcostal incision, although bulky lesions may require extension into the right hemithorax to gain adequate vascular control during dissection. Ascitic fluid is obtained for cytologic examination. If the lesion is deemed unresectable, the tumor is biopsied. If the lesion is made resectable following chemotherapy, lobectomy or trisegmentectomy is performed. Intraoperative cholangiography is helpful to verify the integrity of the remaining biliary tree.

Postoperative complications include bleeding, biliary fistula, subphrenic fluid collections or abscess, and inadvertent injury to the biliary tree. Hepatic regeneration occurs quickly, and hepatic insufficiency is rare if 25% or more of the liver parenchyma remains. Hepatic transplantation is used for unresectable disease when chemotherapy has failed to allow complete resection but no demonstrable metastases exist.

The overall survival for all children with hepatoblastoma is approximately 50%. The best survival (90%) is seen in patients with stage I tumors who receive adjunctive chemotherapy after complete excision. Survival decreases as the surgical stage increases, though long-term survival approaches 60%-70% in patients with unresectable disease who receive chemotherapy.

2. Hepatocellular Carcinoma

Hepatocellular carcinoma is less common than hepatoblastoma and typically presents in older children and adolescents (median age, 10 years). It is associated with preexisting chronic hepatitis, cirrhosis due to hepatitis B virus, and other causes of childhood cirrhosis (tyrosinemia, biliary cirrhosis, α₁-antitrypsin deficiency, type 1 glycogen storage disease, and long-term parenteral nutrition). Signs and symptoms consist of an abdominal mass or diffuse swelling, abdominal pain, weight loss, anorexia, and jaundice. The serum AFP level is elevated in 50%, though the absolute levels are lower than in patients with hepatoblastoma. Diagnostic studies, staging, and treatment are somewhat the same as for hepatoblastoma. Because of multicentricity, bilobar involvement, portal vein invasion, and lymphatic metastases, only 15%-20% of hepatocellular carcinomas are resectable. Fibrolamellar hepatocellular carcinoma in younger patients is associated with a high rate of resectability and a better prognosis. The overall long-term survival is poor (15%), even for resectable disease. The role of liver transplantation is unclear.

3. Liver Hemangioma

This is the most common benign pediatric hepatic lesion. These tumors are solitary (cavernous hemangioma) or multiple (infantile hemangioendothelioma), involving the bulk of the liver. Isolated cavernous hemangiomas are not often associated with cutaneous hemangiomas, whereas infantile hemangioendotheliomas are commonly associated with hemangiomas in other parts of the body or integument. Patients with a solitary hemangioma frequently have no symptoms or present with a mass. Infrequently there is intratumor hemorrhage or rupture resulting in abdominal pain. Infants with hemangioendothelioma commonly present with massive hepatomegaly and high-output cardiac failure from arteriovenous shunting. Approximately 40% develop Kasabach-Merritt syndrome (thrombocytopenic coagulopathy due to platelet sequestration within the tumor). The diagnosis is made by red blood cell-labeled radionuclide or dynamic abdominal CT scanning. CT scan demonstrates increased filling and a rapid venous phase from arteriovenous shunting. Angiography is unnecessary, and percutaneous biopsy is contraindicated.

Treatment is not necessary in an asymptomatic child. Patients with congestive heart failure or thrombocytopenia are treated with corticosteroids, digoxin, and diuretics. Refractory patients benefit from hepatic artery embolization. External beam radiation reduces hepatic size and controls symptoms. Their large size and diffuse involvement often preclude resection. Indications for surgery include ruptured lesions with hemorrhage, masses with uncertain diagnoses, symptomatic lesions, or disease limited to one lobe. Hemangioendotheliomas may undergo malignant degeneration into angiosarcoma.

Accidental trauma is the leading cause of death among children 18 and younger. Patterns of injury vary by age, with a higher rate of isolated neurotrauma than adults. Mortality has been reduced in recent years due to a combination of factors including prevention, improved prehospital care and evolving management strategies. Pediatric trauma has a trimodal distribution of mortality. Early mortality is from massive injury to the CNS or central vasculature and can only be addressed by prevention. Mortality within hours from the time of injury is due to CNS mass lesions (brain bleeding or edema), solid organ injury with hemorrhage and pleural of pericardial compression. The rapid diagnosis and treatment of these conditions improves outcome and is the focus of advanced trauma life support courses. Late mortality seen days to weeks after injury is due to septic and inflammatory complications. This is less common in children than adults. Pediatric surgery has led the development of nonoperative management of spleen and liver laceration that has led to significant organ preservation.

Child abuse is any nonaccidental injury inflicted by a parent, guardian, or other supervising adult. It may be passive, in the form of emotional or nutritional deprivation, but is most readily recognized in the active form, characterized as “battered, bruised, beaten, broken, and burned.” It is estimated that 1 million children per year in the United States suffer injuries that qualifying for reporting to the National Center on Child Abuse and Neglect. About 20%-50% of children are rebattered after the first diagnosis, resulting in death in 5% and permanent physical damage in 35% when the syndrome is not recognized.

The child abuser is usually a young, insecure, unstable person who had an unhappy childhood and who has unrealistic expectations of the child. Most of these individuals are of low socioeconomic status. The abuser may be a parent, guardian, babysitter, neighborhood child, or other close associate. Active traumatic abuse is usually perpetrated by the father, but passive neglect with failure to thrive from nutritional or emotional deprivation is usually attributable to the mother.

Clinical Findings

In most cases, the battered child is under 3 years of age and is the product of a difficult pregnancy or premature labor, usually unwanted or born outside of a stable parental relationship. Many battered children have congenital anomalies or are hyperkinetic and colicky. In most cases there is a discrepancy between the history supplied and the magnitude of the injury—or else a reluctance to give a history. Contradictory histories or delay in bringing the child to medical attention—or taking the child to many different emergency room visits in different hospitals for unusual reasons—should be regarded with suspicion. A past injury in the child or sibling and almost any injury in an infant less than 1 year of age should trigger a consideration of child abuse. The parents may be evasive or hostile. They may have open guilt feelings or may be capable of complete concealment. The innocent spouse is usually more protective of the abuser than of the child.

The child is usually withdrawn, apathetic, whimpering, and fearful and shows signs of neglect or growth retardation. Multiple forms of injury may be noted at varying stages of healing. The child should be completely disrobed to enable the clinician to look for welts, bruises, lacerations, bite or belt wounds, stick or coat hanger marks on the head, trunk, buttocks, or extremities, and similar evidence of mistreatment. Cigarette, hot plate, match, or scalding burns may be evident. Subgaleal hematomas may be caused by pulled hair. Retinal hemorrhage or detachment may follow blows to the head. Abdominal injuries may produce laceration to the liver, spleen, or pancreas or bowel perforation. Sexual abuse should be identified by determining whether the vaginal introitus or anus is bruised, lacerated, or enlarged and whether aspirated fluid contains sperm or prostatic acid phosphatase.

Even though no obvious fracture may be present, a skeletal radiographic survey should be performed. The bone most commonly fractured is the femur, followed by the humerus in the region of the diaphysis. Rib fractures and periosteal reactions in various stages of healing will be seen. Skull fractures are most commonly seen in infants less than 1 year old. Suture separation of the skull may indicate subdural hematoma. Neurologic injury may require a CT or MRI scan.

Treatment

The child should be admitted to hospital to be protected until the home environment can be evaluated. Injuries should be documented radiographically and with photographs. The presence of sperm in the vagina or anal canal should be confirmed. Bleeding disorders should be evaluated by a platelet count, bleeding time, prothrombin time, and plasma thromboplastin test to make certain that multiple bruises are not due to coagulopathy. A serologic test for syphilis may be indicated as well as cultures (including pharyngeal) for gonorrhea.

Injuries should be treated. Consultation with ophthalmologists, neurologists, neurosurgeons, orthopedic surgeons, and plastic surgeons may be required.

It is required by law in every state for both the hospital and the physician to report child abuse (suspected as well as documented) to local child protection services, usually via the hospital’s social work department. The physician is the protector of the child and a consultant to the parents and must not assume the role of prosecutor or judge. The most difficult task is to notify the parents without confrontation, accusation, or anger that battering or neglect is suspected. The physician must tell the parents that the law requires reporting injuries that are unexplained or inadequately explained in view of the nature of the injury. A written referral should then be made to other professionals, such as child welfare personnel, hospital social workers, or psychiatrists. The referral should describe the history of past injuries and the nature of current injuries, results of physical examination and laboratory and x-ray studies, and a statement about why nonaccidental trauma is suspected.

Prognosis

The abuser may require careful evaluation for possible psychosis by a psychiatrist. Child welfare personnel and social workers will have to assess the home environment and work with the parents to prevent future abuse. It may be necessary to place the child in a foster home, but approximately 90% of families can be reunited.