Chapter 12. Management of Abdominal Trauma

Introduction

The management of penetrating abdominal trauma parallels the evolution of diagnostic modalities. In the 19th century, expectant (observation) management was the approach of choice worldwide. In 1880, Paule Reclese, a French surgeon, advocated supportive care only for penetrating abdominal injuries. Sir William McCormick, chief Army Surgeon during this same period, coined the McCormick aphorism regarding the management of gunshot wounds to the abdomen that stated “if a man undergoes surgery after being shot he dies and lives if left in peace.” Even with a mortality rate that was exceedingly high, such dogma was the standard of care during this era for any penetrating abdominal trauma. This management approach was, unfortunately, applied when President James A. Garfield sustained a gunshot wound to the abdomen. The observational management, called the “Garfield Death Watch,” by the President's medical team resulted in the demise of President Garfield. There were very few voices that challenged this surgical dogma of nonoperative management, with Dr Marion Simms, a prominent Southern surgeon who became president of the American Medical Association, being the most vocal.1 With predictably overwhelming morbidity/mortality associated with these injuries, it became apparent that a more aggressive, interventional approach was needed for penetrating injuries to the abdomen, and, as a result, mandatory exploration, or celiotomy, became the prevailing management option of choice and essentially the standard of care.

Shafton and Nance's landmark articles, which emphasized surgical judgment in the management of penetrating wounds of the abdomen, changed the approach to penetrating abdominal injuries from mandatory celiotomy to a more selective management.2,3 Enhanced diagnostic imaging has greatly assisted in making the nonoperative/selective management a more reliable and acceptable treatment option in penetrating abdominal trauma.

Initial Trauma Management

Before focusing on the specific anatomical region where there is an obvious traumatic injury, an initial assessment of the entire patient is imperative. The concept of initial assessment includes the following components: (1) rapid primary survey, (2) resuscitation, (3) detailed secondary survey (evaluation), and (4) reevaluation. Such an assessment is the cornerstone of the Advanced Trauma Life Support (ATLS) program.4 Integrated into primary and secondary surveys are specific adjuncts. Such adjuncts include the application of electrocardiographic monitoring and the utilization of other monitoring modalities such as arterial blood gas determination, pulse oximetry, the measurement of ventilatory rate and blood pressure, insertion of urinary and/or gastric catheters, and incorporating necessary x-rays and other diagnostic studies, when applicable, such as focused abdominal sonography for trauma (FAST) examination, other diagnostic studies (plain radiography of the spine/chest/pelvis and computed tomography [CT]), and diagnostic peritoneal lavage (DPL). Determining the right diagnostic study depends on the mechanism of injury and the hemodynamic status of the patient.

The focus of the primary survey is to both identify and expeditiously address immediate life-threatening injuries. Only after the primary survey is completed (including the initiation of resuscitation) and hemodynamic stability is addressed, should the secondary survey be conducted, which entails a head-to-toe (and back-to-front) physical examination, along with a more detailed history.

Primary Survey

Only the emergency care disciplines of medicine have a two-tier approach to their initial assessment of the patient, with primary and secondary surveys being integral components. As highlighted previously, the primary survey is designed to quickly detect life-threatening injuries.

Therefore, a universal approach has been established with the following prioritization:

• Airway maintenance (with protection of the cervical spine)
• Breathing (ventilation)
• Circulation (including hemorrhage control)
• Disability (neurologic status)
• Exposure/environmental control

Such a systematic and methodical approach (better known as the ABCDEs of the initial assessment) greatly assists the surgical/medical team in the timely management of those injuries that could result in a poor outcome.

1. Airway assessment management (along with cervical spine protection): Because loss of a secure airway could be lethal within 4 minutes, airway assessment/management always has the highest priority during the primary survey of the initial assessment of any injured patient, irrespective of the mechanism of injury or the anatomical wound. The chin lift and jaw thrust maneuvers are occasionally helpful in attempting to secure a patient airway. However, in the trauma setting, the airway management of choice is often translaryngeal, endotracheal intubation. If this cannot be achieved due to an upper airway obstruction or some technical difficulty, a surgical airway (needle or surgical cricothyroidectomy) should be the alternative approach. No other management can take precedence over obtaining an appropriate airway control. Until adequate and sustained oxygenation can be documented, administration of 100% oxygen is required.

2. Breathing (ventilation assessment): An airway can be adequately established and optimal ventilation still not be achieved. For example, such is the case when there is an associated tension pneumothorax (other examples include a tension hemothorax, open pneumothorax, or a large flail chest wall segment). Worsening oxygenation and an adverse outcome would ensue unless such problems are expeditiously addressed. Therefore, assessment of breathing is imperative, even when there is an established and secure airway. A patent airway but poor gas exchange will still result in a poor outcome. Tachypnea, absent breath sounds, percussion hyperresonance, distended neck veins, and/or tracheal deviation are all consistent with inadequate gas exchange. Decompression of the pleural space with a needle/chest tube insertion should be the initial intervention for a pneumo-/hemothorax. A large flail chest, with underlying pulmonary contusion, will likely require endotracheal intubation and the administration of positive-pressure ventilation.

3. Circulation assessment (adequacy of perfusion management): The most important initial step in determining adequacy of circulatory perfusion is to quickly identify and control any active source of bleeding, along with restoration of the patient's blood volume with crystalloid fluid resuscitation and blood products, if required. Decreased levels of consciousness, pale skin color, slow (or nonexistent) capillary refill, cool body temperature, tachycardia, or diminished urinary output are all suggestive of inadequate tissue perfusion. Optimal resuscitation requires the insertion of two large-bore intravenous lines and infusion of crystalloid fluids (warmed). Adult patients who are severely compromised will require a fluid bolus (2 L of Ringer's lactate or saline solution). Children should receive a 20 mL/kg fluid bolus. Blood and blood products are administered as required. Along with the initiation of fluid resuscitation, emphasis needs to remain on identifying the source of active bleeding and stopping the hemorrhage. For a patient in hemorrhagic shock, the source of blood loss will be an open wound with profuse bleeding, or within the thoracic or abdominal cavity, or from an associated pelvic fracture with venous or arterial injuries. Disposition (operating room, angiography suite, etc) of the patient depends on the site of bleeding. For example, a FAST assessment that documents substantial blood loss in the abdominal cavity in a patient who is hemodynamically labile dictates an emergency celiotomy. However, if the quick diagnostic workup of a hemodynamically unstable patient who has sustained blunt trauma demonstrates no blood loss in the abdomen or chest, the source of hemorrhage could be from a pelvic injury that would likely necessitate angiography/embolization if external stabilization (eg, a commercial wrap or binder) of the pelvic fracture fails to stop the bleeding. Profuse bleeding from open wounds can usually be addressed by application of direct pressure or occasionally ligating torn arterial vessels that can easily be identified and isolated.

4. Disability assessment/management: Only a baseline neurologic examination is required when performing the primary survey in order to determine neurologic function deterioration that might necessitate surgical intervention. It is inappropriate to attempt a detailed neurologic examination initially. Such a comprehensive examination should be done during the secondary survey or evaluation. This baseline neurologic assessment could be the determination of the Glasgow coma scale (GCS), with an emphasis on the best motor or verbal response, and eye opening. An alternative approach for a rapid neurologic evaluation would be the assessment of the pupillary size and reaction, along with establishing the patient's level of consciousness (alert, responds to visual stimuli, responds only to painful stimuli or unresponsive to all stimuli). The caveat that must be highlighted is the fact that neurologic deterioration can occur rapidly and that a patient with a devastating injury can have a lucid interval (eg, epidural hematoma). Because the leading causes of secondary brain injury are hypoxia and hypotension, adequate cerebral oxygenation and perfusion are essential in the management of a patient with neurologic injury.

5. Exposure/environmental control: In order to perform a thorough examination of a patient, he/she must be completely undressed. This often requires cutting off the garments to safely expedite such exposure. However, care must be taken to keep the patient from becoming hypothermic. Adjusting the room temperature and infusing warmed intravenous fluids can help establish an optimal environment for the patient.

Secondary Survey

The secondary survey should not be done until the primary survey has been completed and resuscitation initiated, with some evidence of normalization of vital signs. It is imperative that this head-to-toe evaluation be performed in a detailed manner in order to detect less obvious or occult injuries. This is particularly important in the unevaluable (eg, head injury or severely intoxicated) patient. The physical examination should include a detailed assessment of every anatomical region, including the following:

• Head
• Maxillofacial
• Neck (including cervical spine)
• Chest
• Abdomen
• Perineum (including the rectum and genital organs)
• Back (including the remaining spinal column)
• Extremities (musculoskeletal)

A full neurologic examination needs to be performed, along with an estimate of the GCS score if one was not done during the primary survey. The secondary survey and the utilization (when applicable) of the armamentarium of diagnostic adjuncts, previously mentioned, will allow detection of more occult or subtle injuries that could, if not found, account for significant morbidity and mortality. When possible, the secondary survey should include a history of the mechanism of injury, along with vital information regarding allergies, medications, past illnesses, recent food intake, and pertinent events related to the injury.

It cannot be overemphasized that frequent reevaluation of the injured patient is necessary in order to detect any deterioration in the patient status. This sometimes requires repeating both the primary and secondary surveys.

Topography and Clinical Anatomy

The abdomen is often defined as a component of the torso that has for its superior boundary the left and right hemidiaphragm, which can ascend to the level of the nipples (fourth intercostal space) on the frontal aspect and to the tip of the scapula in the back. The inferior boundary of the abdomen is the pelvic floor. For clinical purposes, it is helpful to further divide the abdomen into four areas: (1) anterior abdomen (below the anterior costal margins to above the inguinal ligaments and anterior to the anterior axillary lines), (2) intrathoracic abdomen (from the nipple or the tips of the scapula to the inferior costal margins), (3) flank (inferior scapular tip to the iliac crest and between the posterior and anterior axillary lines), and (4) back (below the tips of the scapula to the iliac crest and between the posterior axillary lines). The majority of the digestive system and urinary tract, along with a substantial network of vasculature and nerves, are contained with the abdominal cavity. A viscera-rich region, the abdomen can often be the harbinger for occult injuries as a result of penetrating wounds, particularly in the unevaluable abdomen as the result of a patient's compromised sensorium.

Mechanism of Injury

In addition to the hemodynamic status of the patient, important variables in the decision making regarding management of penetrating abdominal injuries are both the mechanism and location of injury (see Physical Examination). The kinetic energy generated by hand-driven weapons, such as knives and sharp objects, is substantially less than what is caused by firearms. Although not always evident, it is important to know the length and width of the wound along with the depth of penetration of the weapon or device that caused the stab injury. For example, a stab injury usually results in a long, more shallow wound that does not penetrate the peritoneum. Local wound management is the primary focus for these injuries with no concern for any potential intra-abdominal injury.5 Although there are some stab wounds that do not penetrate the peritoneal cavity, such cannot be assumed without some formal determination or serial abdominal examinations to assess for worsening abdominal tenderness or the development of peritoneal signs.

There is notable variability among the full spectrum of firearms in the civilian setting, with this arsenal, including mostly handguns, rifles, shotguns, and air guns. The kinetic energy, which correlates with the wounding potential, is dependant on mass and velocity (KE = 1/2 mr2). Therefore, the higher the velocity, the greater the wounding potential.6 Because the barrel is longer in a rifle than a handgun, the bullet has more time to accelerate—generating a much higher velocity. A high-velocity missile is propelled at 2500 ft/s or greater. Air guns usually fire pellets (eg, BBs) and are associated with a lower velocity and wounding potential. Shotguns fire a cluster of metal pellets, called a shot. The pellets separate after leaving the barrel, with a rapidly decreasing velocity. At a distance, the wounding potential is diminished. However, at close range (<15 ft), because of the increase in aggregate mass, the tissue destruction is similar to a high-velocity missile injury.

Although each injury should be handled on an individual basis, there are general principles that will provide some guidance in the management of penetrating injuries based on mechanism of injury. Regarding stab wounds, approximately one-third of the wounds do not penetrate the peritoneum and only half of those that do penetrate require operative intervention. The number of organs injured and the intra-abdominal sepsis complication rate are significantly less than wounds caused by gunshots.7,8

Physical Examination

A complete and thorough physical examination of the entire body is essential in the management of penetrating abdominal injury. There are some findings (Table 12-1) on physical examination that are absolute indications for operative intervention. The components of the physical examination should include careful inspection, palpation, and auscultation.

In addition to being able to determine the location, extent, and the number of wounds, inspection can sometimes determine the trajectory of the missile or other wounding agent and, consequently, guide management decisions. For example, a patient with a documented, superficial tangential gunshot wound (low-velocity), with no other remarkable physical findings, would likely be managed expectantly (observation). However, if a penetrating abdominal injury results in a patient presenting with an evisceration, exploratory laparotomy would be the management option of choice. Palpation will enable the examiner to elicit abdominal tenderness or frank peritoneal signs, along with being able to detect abdominal distention and rigidity. On occasion, missiles can be palpated lodged in the soft tissue. Unless in a controlled and sterile setting such as the operative theatre, probing of a wound should be avoided. Auscultation is also an important component of the physical examination. It can help determine diminished or absent bowel sounds that could be suggestive of evolving peritonitis. Also, auscultation could detect a trauma-induced bruit, suggestive of a vascular injury.

The examiner has to be keenly aware of the fact that there are situations in which the abdominal examination will be unreliable due to possible spinal cord injury or a patient's altered mental state.

Diagnostic Studies

Even with penetrating injuries, the abdomen is notorious for hiding its secrets—occult injuries. Access to an extensive diagnostic armamentarium is imperative in the optimal management of these injuries. Strongly advocated by some for abdominal stab wounds, local wound exploration has the advantage of allowing the patient to be discharged from the trauma bay or emergency department, if surgical exploration of the wound fails to demonstrate penetration of the posterior fascia and peritoneum. However, if the patient has to go to the operating room for other injuries, the local wound exploration should be done in the surgical suite that will have better lighting and a more sterile environment. A positive finding during local wound exploration dictates a formal laparotomy or laparoscopy. However, even with local wound exploration as a guide, the nontherapeutic laparotomy rate can be high, given that only a third of the patients with stab wounds to the anterior abdomen require therapeutic laparotomies.9,10 In the patient who has an evaluable abdomen, serial abdominal examinations would be an acceptable alternative to local wound exploration, in order to determine the need for operative intervention. Local wound exploration should only be done for stab wounds to the anterior abdomen. Such an approach is potentially too hazardous for thoracoabdominal penetrating injuries and back/flank wounds. Plain radiography (abdomen/pelvis/chest) can be pivotal in documenting the presence of missiles and other foreign bodies and determining the trajectory of the injury tract, particularly for wounds from firearms. Also, the presence of free air might be confirmed by plain radiography. Unless there is concern about a retained broken blade, there is little utility for plain radiography for stab injuries.11 The DPL developed by David Root in 1965, was a major advance in the care of the hemodynamically labile patient who sustained blunt trauma.12 With the advent of FAST and rapid CT, DPL has very limited utility. DPL has never had a broad appeal in the diagnostic evaluation of penetrating abdominal wounds. Although some have advocated its use with tangential wounds of the abdominal wall, the technique has failed to receive widespread support.13 Its reliability in detecting clinically significant injuries sustained as a result of penetrating abdominal injuries has been a prevailing concern.14–16 The reported sensitivity and specificity of DPL for abdominal stab wounds are 59–96% and 78–98%, respectively.17 Also, DPL is a poor diagnostic modality for detecting diaphragmatic and retroperitoneal injuries.

Diagnostic imaging has had the greatest impact in changing the face of trauma management with CT taking the lead in this area. Its ubiquitous presence in the management of blunt abdominal trauma is well established. However, it is becoming an important diagnostic study in the evaluation of penetrating abdominal injuries. In addition to its excellent sensitivity in detecting a pneumoperitoneum, free fluid, and abdominal wall/peritoneal penetration, CT is helpful in identifying the tract of the penetrating agent. Hauser et al recommended the use of “triple contrast” CT in the assessment of penetrating back and flank injuries.18 CT scan evaluation is an essential diagnostic tool in the increasing advocacy for selective management of abdominal gunshot wounds obviating the need for mandatory surgical exploration.19 However, there still remain two major limitations of CT: detection of an intestinal perforation and a diaphragmatic injury.

Unless the injury is confined to the solid organ of the abdomen, such as the liver or spleen, the matrix of intestinal gas patterns makes detection of penetrating injuries difficult. Kristensen et al were one of the first teams to introduce the role of ultrasonic scanning as part of the diagnostic armamentarium in trauma management.20 Kimura and Otsuka endorsed using ultrasonography in the emergency room for evaluation of hemoperitoneum.21 FAST does not have the same broad application in the evaluation of penetrating trauma as it does in blunt trauma assessment. Rozycki et al reported on the expanded role of ultrasonography as the “primary adjuvant modality” for the injured patient assessment.22 Rozycki et al also reported that FAST examination was the most accurate for detecting fluid within the pericardial sac. Such a finding would be confirmatory for a cardiac injury and possible cardiac tamponade, given a mechanism of injury that could result in an injury to the heart.

As a diagnostic modality, laparoscopy is not a new innovation. Other specialists have been utilizing this operative intervention for several decades. However, it was formally introduced as a possible diagnostic procedure of choice for specific torso wounds when Ivatury et al did a critical evaluation of laparoscopy on penetrating abdominal trauma.23 Fabian et al also reported on the efficacy of diagnostic laparoscopy in a prospective analysis.24 With there being no conventional diagnostic tool that can conclusively rule out a diaphragmatic laceration or rent, diagnostic laparoscopy becomes the study of choice for penetrating thoracoabdominal injuries, particular left thoracoabdominal wounds (Fig. 12-1). Laparoscopy can also be used to determine peritoneal entry from a tangential penetrating injury.

Penetrating Abdominal Injuries and the Hemodynamically Stable and Unstable Patient

As highlighted previously, the management principles in patients who sustain penetrating abdominal injuries and remain hemodynamically stable depend on the mechanism and location of injury, along with the hemodynamic status of the patient. Irrespective of the patient's hemodynamic parameters, the ATLS protocol should be strictly followed upon arrival of the patient to the trauma bay.25Figures 12-2 through 12-5 are management algorithms for the patient with penetrating thoracoabdominal, penetrating anterior abdominal, penetrating abdominal, or penetrating back or flank injuries.

Trauma Laparotomy

The operative theater should be large enough to accommodate more than one surgical team, in the event the patient might require simultaneous procedures to be performed. In addition, the room should have the capability of maintaining room temperatures in order to avoid having a hypothermic patient. Also, there should be a rapid transfusion device in the room in order to facilitate the delivery of large fluid volume and ensure that the fluid administration is appropriately warm.

Abdominal exploration for trauma has basically four imperatives: (1) hemorrhage control, (2) contamination control, (3) identification of the specific injury(ies), and (4) repair/reconstruction. The abdomen is prepared with a topical antimicrobial from sternal notch to bilateral midthighs and extending the prep laterally to the side of the operating room table, followed by widely draping the patient. Such preparation allows for expeditious entry into the thorax if needed and possible vascular access or harvesting. Exploration is initiated with a midline vertical incision that should extend from the xyphoid to the symphysis pubis in order to achieve optimal exposure.

The first priority upon entering the abdomen is control of exsanguinating hemorrhage. Such control can usually be achieved by direct control of the lacerated site or obtaining proximal vascular control. After major hemorrhage is controlled, blood and blood clots are removed. Abdominal packs (radiologically labeled) are used to tamponade any bleeding and allow for identification of any injury bleeding. The preferred approach to packing is to divide the falciform ligament and retract the anterior abdominal wall. This will allow manual placement of the packs above the liver. Abdominal packs should also be placed below the liver. This arrangement of the packs on the liver creates a compressive tamponade effect. After manually eviscerating the small bowel out of the cavity, packs should be placed on the remaining three quadrants, with care taken to avoid an iatrogenic injury to the spleen. During the packing phase after ongoing hemorrhage has been controlled, the surgeon should communicate with the anesthesia team that major hemorrhage has been controlled and that this would be an optimal time to establish a resuscitative advantage with fluid/blood product administration.

The next priority should be control or containment of gross contamination. This begins with the removal of the packs from each quadrant—one quadrant at a time. Packs should be removed from the quadrants that you least suspect to be the source for blood loss, followed by removal of the packs from the final quadrant—the one that you believe is the area of concern.

After control of major hemorrhage has been achieved, any evidence of gross contamination must be addressed immediately. Obvious leakage from intestinal injury can be initially controlled with clamps (eg, Babcock clamp), staples, or sutures. The entire abdominal gastrointestinal tract needs to be inspected, including the mesenteric and antimesenteric border of the small and large bowel, along with the entire mesentery. Rents in the diaphragm should also be closed to prevent contamination of the thoracic cavity.

Further identification of any and all intra-abdominal injuries should be initiated. Depending on the mechanism of injury and the estimated trajectory of the wounding agent, a thorough and meticulous abdominal exploration should be performed, including entering the lesser sac to better inspect the pancreas and the associated vasculature. In addition, mobilization of the C-loop of the duodenum (Kocher maneuver) might be required, along with medial rotation of the left and/or right colon for exposure of vital retroperitoneal structures.

The final component of a trauma laparotomy is definitive repair, if possible, of specific injuries. As will be highlighted later in the chapter, the status of the patient dictates whether each of the components of a trauma laparotomy can be achieved at the index operation. A staged celiotomy (“damage-control” laparotomy) might be necessary if the patient becomes acidotic, hypothermic, coagulopathic, or hemodynamically compromised.

Definitive Management of Specific Injuries

Small Intestines

Isolated small bowel enterotomies can be closed primarily with nonabsorbable sutures for a one-layer closure. If the edges of the enterotomy appear nonviable, they should be gently debrided prior to primary closure. However, multiple contiguous small bowel holes or an intestinal injury on the mesenteric border with associated mesenteric hematoma will likely necessitate segmental resection and anastomosis of the remaining viable segments of the small bowel. The operative goal is always the reestablishment of intestinal continuity without substantial narrowing of the intestinal lumen, along with closure of any associated mesenteric defect. Application of noncrushing bowel clasps can contain ongoing contamination while the repair is being performed. Although a hand-sewn or stapler-assisted anastomosis is operator dependant, trauma laparotomies are time-sensitive interventions and expeditious management is imperative.

Colon

The segment of injured bowel should be thoroughly inspected, particularly missile injuries that are most common, for through-and-through enterotomies. This requires adequate mobilization of the colon in order to visualize the entire circumference of the bowel wall. Initially controversial, an enterotomy (right- or left-sided injuries) of the colon can be closed primarily, irrespective of contamination or transient shock state.26 If the colon injury is so extensive that primary repair is not possible or would severely compromise the lumen, a segmental resection should be performed. Depending on the setting, the remaining proximal segment can be anastomosed to the distal segment or a proximal ostomy and Hartmann's procedure can be performed. If the distal segment is long enough, a mucous fistula should be established. Documented rectal injuries, below the peritoneal reflection should necessitate a diverting colostomy and presacral drainage (exiting from the perineum). Such drainage is, however, not universally endorsed.

Stomach/Duodenum

With respect to penetrating wounds of the stomach, the anterior and posterior aspects of the stomach need to be meticulously inspected for accompanying through-and-through injuries. Penetrating injuries of the stomach should be repaired primarily after debridement of nonviable edges. The primary repair can either be performed in a single layer with nonabsorbable suture or as a double layer closure with an absorbable suture (eg, Vicryl) for the first layer and the second layer being closed with unabsorbable sutures (eg, silk). There are very few penetrating injuries of the stomach that would compromise the gastric lumen. Also, it is unlikely that primary repair of a through-and-through stomach injury would compromise the gastric lumen. Duodenal injuries can be repaired primarily in a one- or two-layered fashion if the penetration is less than half the circumference of the duodenum. However, for more complex duodenal injuries, an operative procedure is needed to divert gastric contents away from the site (where closure of the wound has been attempted). Performing a pyloric exclusion with the establishment of a gastrojejunostomy is such a procedure.27–29

Pancreas

Superficial or tangential penetrating wounds of the pancreas, in which there is not an injury to the main pancreatic duct, can be externally drained. However, a penetrating injury that transects the pancreas, including the main pancreatic duct, requires extirpation of the distal pancreas (distal pancreatectomy), particularly if the transection site is to the left of the superior mesenteric vessels. A more proximal penetrating injury that involves the main pancreatic duct, with associated complex duodenal injury (eg, injury to the ampulla), would likely necessitate a pancreatoduodenectomy. Unfortunately, because of the rich vascular network surrounding the pancreas, penetrating pancreatic wounds can be lethal injuries.

Spleen

Most penetrating splenic injuries, particularly gunshot wounds, require a splenectomy. In order to visualize the entire spleen, it should be mobilized to the midline by dividing its ligamentous attachments. Superficial penetrating injuries of the spleen can sometimes be managed by either splenorrhaphy or application of a topical hemostatic agent. Splenorrhaphy can be done by a pledgeted repair or an omental buttress. However, complex repair of the spleen is not a prudent approach in the always time-sensitive trauma setting.

Gallbladder and Liver

Penetrating injuries to the gallbladder dictate the need for extirpation. There is no role for primary repair of a penetrating wound to the gallbladder.

Liver injuries are common in both blunt and penetrating trauma. The majority of injuries are superficial or minor and require no surgical repair. Simple application of pressure and/or a hemostatic agent or fibrin glue will constitute definitive management of the majority of these injuries. The argon beam coagulator, also a helpful adjunct in superficial hepatic injuries with persistent oozing, generates ionizing energy through an argon gas stream that causes rapid coagulation. The operative armamentarium for complex penetrating hepatic injuries is highlighted in Table 12-2.

Genitourinary System

Fewer than 10% of patients with penetrating abdominal wounds sustain genitourinary tract injuries. The majority of the injuries are renal. Penetrating injuries that result in a grade IV (cortical/calyceal injury and associated vascular injury with contained hemorrhage) or grade V (shattered kidney and vascular avulsion) invariably necessitate a nephrectomy, particularly if there is a viable contralateral kidney. Lacerations or more superficial wounds of the kidney might require renorrhaphy, with approximation of the disrupted capsule with pledgeted sutures or a prosthetic (mesh) wrap. Absorbable interrupted suture should be used and all repairs should be drained. The injury pattern might dictate the need for a partial nephrectomy. Ureteral injuries can be extremely difficult to identify in penetrating wounds with an accompanying retroperitoneal hematoma. When possible, the ureter should be repaired primarily with interrupted absorbable suture over a double J-stent. A complete transection of the ureter requires debridement of the nonviable edges and the ends being spatulated, with and primary repair over a stent. All repair sites should be adequately drained. If the anastomosis cannot be performed in a tension-free fashion, a bladder flap (Boari) could be surgically constructed, with implantation of the proximal segment of the transected ureter into the flap. A psoas “hitch” might be required if there is any tension on the flap and the tunneled ureter.

Penetrating injury to the intraperitoneal bladder requires surgical repair. After no involvement of the trigone is confirmed, the bladder should be closed with a two-layer closure with absorbable suture (the second layer incorporates Lembert sutures to imbricate the first layer). Suprapubic drainage should only be done selectively; however, a Foley catheter should be left in place.

Retroperitoneal Hematomas

The retroperitoneum, an organ-rich region, has several vital structures that can be injured when its boundaries are penetrated. It can be a major potential site for hemorrhage in patients sustaining either penetrating or blunt trauma due to the substantial vascularity along with bleeding that can occur from an associated solid organ wound (eg, kidney). In the central region (zone 1) of the retroperitoneum reside the abdominal aorta; celiac axis; and the superior mesenteric artery, vena cava, and proximal renal vasculature. The lateral retroperitoneum (zone 2) encompasses the proximal genitourinary system and its vasculature. The pelvic retroperitoneum (zone 3) contains the iliac arteries, veins, and tributaries of veins. In addition to the vasculature and the kidneys (plus ureters) highlighted above, the retroperitoneum contains the second, third, and fourth portions of the duodenum, along with the pancreas, the adrenals, and the intrapelvic portion of the colon and rectum. Table 12-3 underscores the management principles of trauma-related retroperitoneal hematomas. Ideally, proximal (and when applicable, distal) control need to be achieved before exploring any retroperitoneal hematoma. For retroperitoneal hematomas in zone 1, mandatory exploration is required irrespective of a penetrating or blunt mechanism. Also, retroperitoneal hematoma in any of the three zones requires exploration for all penetrating injuries. For zone 2 retroperitoneal hematomas resulting from blunt trauma, all pulsatile or expanding hematomas should undergo exploration. Gross extravasation of urine also necessitates exploration. Zone 3 (pelvic retroperitoneum) hematomas should be explored only for penetrating injuries to determine if there is a specific intrapelvic colorectal, ureteral, or vascular injury. However, such an approach should not be taken for blunt trauma, for the injury would likely be venous and application of an external compression device would be the preferred intervention. An arterial injury could be addressed by arteriography/embolization.

Intra-Abdominal Packing and “Damage-Control” Strategy

“Damage-control” strategy, popularized by Rotondo et al, is a staged celiotomy strategy that was initially made operational by Mattox and Feliciano and was labeled the “Bogota bag” approach. Although Mattox and Feliciano did not actually develop this approach, they certainly popularized the technique and made it acceptable for use in the United States.30–34 Irrespective of the name given to this strategy of surgically managing only immediate life-threatening injuries (along with intra-abdominal packing and rapid temporary closure of the abdominal cavity), the goal is the same—avoiding the potential irreversibility of sustained acidosis, hypothermia, coagulopathy, and hemodynamic lability by delaying definitive operative management until the patient can be stabilized in the intensive care unit. Although “damage control” is most frequently used in association with severe hepatic wounds, other organ injuries, including vascular wounds, can necessitate this staged celiotomy approach with hepatic packing and a rapid, creative abdominal closure.

Introduction

Management of blunt abdominal trauma has undergone significant change over the past two decades, evolving from a primary operative scheme to more nonoperative management. The workup has shifted largely from the use of physical examination, plain x-ray, laboratory findings, and DPL to the extensive use of CT and ultrasonography. Treatment for visceral injury has traditionally been surgical, but many forms of solid-organ injury can now be managed nonoperatively or with minimally invasive and interventional radiology techniques. Management of the multiply injured trauma patient at level I trauma centers with state-of-the-art techniques has now conclusively shown significantly improved patient outcomes and survival.35

Diagnostic and Imaging Techniques

Diagnostic Peritoneal Lavage

Originally described by Root in 1965, diagnostic peritoneal lavage (DPL) has been a mainstay in the management of blunt abdominal trauma for over four decades.36 Before the era of routine CT scanning, it was used as a screening tool to evaluate patients having blunt or penetrating abdominal trauma with an accuracy rate reported between 92 and 98%.37–42 Because of its invasive nature, DPL has largely been supplanted by CT scans and FAST. However, it remains an excellent tool for further workup of occult bowel injury or in unstable patients when FAST is not available or has questionable findings. In the workup for occult bowel injury, traditional parameters (Table 12-4) should be used to guide therapy. In unstable patients, a diagnostic tap is usually all that is necessary, and exploration indicated for greater than 10 mL of gross blood.

The pitfalls of DPL are a relatively high false-positive rate, risk of creating visceral injury, and poor sensitivity for detecting injury to retroperitoneal structures such as the pancreas and duodenum.43–45 Iatrogenic events are minimized if a Foley catheter and nasogastric tube are placed prior to the procedure. Patients with pelvic fractures and suspected retroperitoneal hematoma or pregnant females should undergo a supraumbilical approach. Visceral injury is less likely with an open approach but more time consuming and invasive.46–49 Checking amylase or lipase in lavagate, concomitant use of CT scan, and a high index of suspicion are necessary to avoid missed retroperitoneal injury.

Focused Abdominal Sonography for Trauma

One of the most recent advances in the workup of the acutely injured patient is the use of bedside ultrasonography for detection of cardiac and intra-abdominal injury. Known as focused abdominal sonography for trauma (FAST), this technique's noninvasive nature allows the operator to perform an examination simultaneously during the initial resuscitation and stabilization of a multiply injured trauma patient. The technique may thereby provide evidence of significant hemorrhage early in the course of an evaluation. An ultrasound probe is used to examine four key windows for fluid: the subxyphoid area permits visualization of the pericardium, the left subcostal area visualization of the splenorenal recess, right subcostal area visualization of Morison's pouch, and the suprapubic area visualization of the pelvic cul-de-sac (Fig. 12-6). The presence of fluid may indicate then presence of cardiac tamponade, intra-abdominal hemorrhage, hollow viscus perforation, hemoperitoneum, or ascites. False-positive results secondary to preexisting ascites or false negatives due to operator error and/or body habitus are the main limitations. Scanning the supra pubic area with distension of the urinary bladder will enhance the sensitivity of the examination for the detection of pelvic fluid. A threshold of at least 200 mL of fluid in the abdominal cavity is necessary for detection, and intra-abdominal injuries must be associated with the presence of this much free fluid for a positive finding.50 Reported sensitivities range between 73 and 88% and specificity between 98 and 100%.51 Accuracy rates range from 96 to 98%. FAST is an inexpensive, rapid, portable, noninvasive technique that can be performed in serial fashion if there is a change in patient stability.52–54 Additionally, it obviates the risk of exposing pregnant females to radiation. Positive findings in stable patients can be further evaluated with CT or DPL while unstable patients with a positive finding may be taken to the operating room for emergent exploration. Workup of a patient with a reliable abdominal examination may be complete with a negative FAST in the absence of abdominal signs or symptoms.

Computed Tomography

Technological advances in CT have revolutionized the initial management of trauma patients over the past two decades. Multidetector scanners have dramatically improved resolution and accuracy of these imaging studies. Negative predictive values as high as 99.63% have been reported for patients sustaining significant mechanisms of blunt trauma allowing the use of CT as a reliable and noninvasive tool for screening patients with blunt abdominal trauma.55 In light of modern-day CT capabilities, prospective data have demonstrated that patients with a signinficant mechanism and a benign abdomen can be released from the emergency department if a CT scan of the abdomen shows no evidence of visceral injury provided that there are no other reasons for hospitalization.55

CT reliably identifies injuries in solid organs such as the spleen, liver, and kidney because of their vascular nature demonstrating disruption of normal architecture, associated free fluid, and the so-called vascular blush.56 Grading scales have been developed to allow for accurate classification and determination of management plan (Tables 12-5 through 12-7).56,57

Detection of bowel injury via CT scan in patients who are intoxicated, intubated, or have associated closed-head injury or other distracting injuries can present a diagnostic challenge in the absence of a reliable abdominal exam. The incidence of blunt bowel injury varies from series to series but is generally reported in the 1–5% range in all blunt trauma patients admitted to level I trauma centers.58,59 A high index of suspicion is predicated on mechanism of injury and physical examination findings such as abdominal wall tattooing and/or the seat belt sign. CT findings may be direct such as extravasation of oral contrast or pneumoperitoneum or more commonly indirect such as bowel wall thickening, stranding of the mesentery, or free fluid in the absence of solid organ injury. Indirect findings may be fairly nonspecific and secondary to bowel edema from resuscitation or preexisting ascites. Reproductive age females may have a small amount of normal or “physiologic” pelvic fluid present sometimes adding to the complexity of the evaluation. Patients on positive pressure ventilation or with significant barotrauma may develop mediastinal or subcutaneous emphysema that can tract through the peritoneum or retroperitoneum and give the appearance of free air. Great care in the radiologic interpretation and close clinical correlation are necessary in such cases. The liberal use of DPL may prevent nontherapeutic laparotomy. Obviously, when significant doubt remains, abdominal exploration may be necessary to confirm an injury.

The role of oral contrast in the evaluation of the acutely injured patient has recently come under question. Little time is usually available in the emergent setting to permit adequate opacification of the small bowel. Patients are further at risk for aspiration of the contrast media, and administration often requires placement of a nasogastric tube. A number of reports now have shown that elimination of oral contrast media does not lead to an increased incident of missed bowel injury.58–60 Many centers have now safely eliminated the use of oral contrast media from their routine trauma protocols expediting management and ease of patient care. Resuscitation edema may cause a hazy appearance around the head of the pancreas and duodenal c-loop raising the question of a pancreas or duodenal injury. Further clarification in this situation can be obtained, when it occasionally occurs, via repeat CT scan with the administration of oral contrast and the injection of 300- to 500-cc bolus of air down the nasogastric tube and may make the pneumoperitoneum obvious.

CT may also be of great importance in identifying patients with arterial hemorrhage related to pelvic fracture. CT imaging may demonstrate an arterial blush or large hematoma in the vicinity of a pelvic fracture indicating the need for pelvic arteriography or pelvic external fixation. A “CT cystogram” may also be helpful and eliminate redundancy of x-ray evaluation. The Foley catheter is clamped after placement in the trauma bay. Real-time interpretation, as the CT scan is performed by the evaluating physician, may dictate further delayed images or a formal three-view (anterior/posterior, lateral, and postvoid views) cystogram.

Specific Organ Injury

The Spleen

The spleen is the most commonly injured intra-abdominal organ followed by the liver and small bowel in blunt trauma patients. The spleen's location in the left upper quadrant lends susceptibility to injury from broken ribs, deceleration, and blunt percussion forces. Clinically, patients with splenic injury may present with hypotension, left upper quadrant pain, or tenderness to palpation or diffuse peritonitis from extravasated blood. Referred pain to the left shoulder on deep inspiration, in face of splenic hematoma, is known as Kehr's sign.

Nonoperative Management.

Most series indicate that approximately 60–80% of patients presenting with blunt splenic injury can be managed nonoperatively at level I or II trauma centers.61–65 Facilities without the resources and experience of a bona fide trauma team may not safely meet the demands of nonoperative management and should consider patient transfer.66 Patients selected for nonoperative management must have stable vital signs, be free of peritoneal signs or other concern for hollow viscus injury, and have no evidence of free extravasation of IV contrast from the splenic parenchyma.

Considerable debate remains regarding risk factors for failure of nonoperative management. Higher splenic injury grade, age greater than 55 years, moderate to large hemoperitoneum, subcapsular hematoma, and portal hypertension have all been suggested to increase the risk of failure. Early reports in the evolution of nonoperative management regarding ASST grade did not demonstrate higher failure rates for higher-grade injury. More recent reports using high-resolution multidetector CT scanners allow better assessment of injury grade. The data from these studies show patients with injury grades III–V to be at increased risk for nonoperative failure.61,63 Age continues to be controversial subject matter in the literature with numerous reports claiming that age greater than 55 years is or is not a risk factor for failure.61,63,67 Documentation of a moderate or large hemoperitoneum is suggestive of a major injury and should be considered a significant factor in individual patient assessment.

Patients with splenic subcapsular hematoma or history of portal hypertension are specific subgroups of patients who deserve special consideration. Patients with subcapsular hematoma in our experience tend to ooze from the raw parenchymal surface and further disrupt the capsule leading to more raw surface area to bleed. These patients are at increased risk for delayed rupture 6 to 8 days following injury and may already be discharged from the hospital if they have isolated injury. Furthermore, splenic embolization is not a very effective treatment of this condition because it usually necessitates coiling of the main splenic artery that can lead to significant pain and abscess formation. A history of portal hypertension or cirrhosis, while not absolute contraindications to nonoperative management, certainly should raise concerns. The general risks of laparotomy in a Childs B or C cirrhotic need to be carefully weighed against the risk of ensuing and worsening coagulopathy. This scenario may, indeed, call for main splenic artery embolization. None of these risk factors alone should dictate the decision to proceed immediately to operative intervention. Nonoperative management does reduce hospital length of stay and transfusion requirement; however, the morbidity of splenectomy should remain low in any surgeon's hands. Overall, the patient's condition, including comorbidities, coagulopathy, and other problems (such as traumatic brain injury, aortic injury and suspicion for concomitant hollow viscus injury) factor into the decision making process. No one should ever succumb to splenic hemorrhage that was undergoing nonoperative management.

Approximately 20% of patients initially undergoing nonoperative management of blunt splenic injury require further intervention. Failure has been associated with the presence of a contrast blush in up to two-thirds of these patients.68 The presence of a contained contrast blush within the parenchyma of the spleen represents pseudoaneurysm formation of a branch of the splenic artery. Angioembolization is now commonly used to selectively occlude the arterial branches containing these injuries.61,62,65,69,70 Implementation of this salvage technique at centers that routinely screen for the presence of pseudoaneurysm has increased the success of nonoperative management to 90% or greater. Pseudoaneurysm formation has been observed in even grades I and II injuries and may not be present on the initial imaging.61,64,70 Therefore, follow-up CT scan is recommended on all patients with splenic trauma within 24–48 hours after injury. If these images show stable injuries without pseudoaneurysm formation, expectant management may ensue. Figure 12-7 is a management algorithm for the patient with blunt splenic injury.

Long-term data are unavailable concerning the risk of outpatient or delayed rupture, but the incidence is low and has been reported to be about 1.4%.71 The average date to readmission for delayed splenectomy after discharge was 8 days in this study. Lower-grade (I, II) injuries tend to heal more quickly and most all injuries are healed by 5–6 weeks.72 However, approximately 20% of blunt splenic injuries will not show complete healing and may be at risk for pseudocyst formation. A CT scan should be repeated in 6 weeks for grades I and II injuries and 10–12 weeks in grades III–V before reinstating normal activity.

Splenectomy.

Patients requiring urgent or emergent intervention for splenic hemorrhage may develop hypothermia, coagulopathy, and visceral edema. The most expeditious and safest course of action under these conditions is removal of the spleen. The general assumption of abdominal exploration for trauma is that there are known and, possibly, unknown injuries. The operative approach is via a midline vertical incision that allows the best exposure and facilitates temporary abdominal closure should visceral edema or damage-control measures be necessary. Standard operating procedure is similar to that previously highlighted in the section, Management of Penetrating Abdominal Trauma.

With respect to performing a splenectomy, a Buckwalter retractor is used to expose the left upper quadrant. The spleen is retracted medially with some downward compression, and the posterior attachments can be taken with the cautery. Once these attachments are freed, the spleen can be mobilized medially for optimal exposure. The assistant stands on the left side of the table and supports the spleen while the surgeon ligates short gastric and hilar vessels. Being careful to avoid the tail of the pancreas, a large clip, placed on the specimen side of the splenic hilum, will reduce back-bleeding and expedite the procedure. Once the spleen has been removed, the splenic fossa is inspected for further bleeding with a rolled laparotomy pad.

Splenorrhaphy.

Hemodynamically stable patients found to have small to moderate amounts of parenchymal hemorrhage at laparotomy may be candidates for splenic preservation. The spleen is mobilized into the wound using the same technique as for splenectomy. The injury to the spleen is assessed and decision is made whether to resect a portion if the parenchymal injury extends into the hilum or if arterial bleeding is coming from within the splenic laceration itself. If the decision is made to resect the upper or lower pole, the parenchyma is divided with the cautery, and the associated hilar vessels are taken with clamps and ties. Any arterial bleeding from the parenchyma is controlled with suture ligature and the cautery is used to control oozing from the parenchyma. A tongue of omentum is then sutured into the laceration or to the raw surface of the remaining spleen in the case of resection. Approximately 50% of the spleen is required to preserve adequate phagocytic and immunologic function. If this cannot be achieved, a splenectomy is probably the best option.

Overwhelming Postsplenectomy Infection.

The incidence of overwhelming postsplenectomy infection (OPSI) following trauma is not well understood because it may not be appreciated when it occurs and it is not routinely reported. However, the reported incidence of OPSI in adult patients undergoing splenectomy for all causes is 0.9% with a mortality of 0.8%.73 The risk of OPSI in adults following trauma is felt to be lower than the incidence seen after splenectomy for hematological disorders such as idiopathic thrombocytopenic purpura (ITP), lymphoma, and thalassemia. Children are at greater risk for OPSI and should receive prophylactic penicillin V 125 mg twice daily until age 3 and then 250 mg twice daily until age 5. Currently, anyone older than 2 years should receive the 23 valent pneumococcal vaccine and a one-time dose of the Haemophilus influenzae and meningococcal vaccine. A one-time booster dose of the pneumococcal vaccine is recommended 5 years after the original vaccine.74

The Liver

The liver is susceptible to the same blunt force mechanisms as the spleen making it the second most frequently injured intra-abdominal organ. Similar to the spleen, nonoperative management of blunt liver injury has greatly reduced transfusion requirements, hospital length of stay, and mortality.75–78 Angiographic embolization of arterial injury has also greatly reduced the morbidity and mortality of liver trauma. Complications of nonoperative management such as biloma and liver abscess can usually be managed with minimally invasive techniques as well. What is imperative in the management scheme is the knowledge of when to take the patient immediately to the operating room for active hemorrhage versus attempting nonoperative management with angioembolization. The liver is obviously not as expendable an organ as the spleen, and there is no substitute for an in-depth knowledge and experience handling hepatic injuries.

Nonoperative Management

Similar to the experience with blunt splenic trauma, routine use of CT scans has revolutionized the management of blunt hepatic trauma. The most recent data show that 70–85% of all patients presenting with blunt liver trauma can be managed nonoperatively.75,76,79,80 Patients must be hemodynamically stable, free of peritoneal signs or other evidence of bowel injury, and have absence of contrast extravasation. Worsening grade of injury makes nonoperative management less likely, but injury grade alone should not dictate the decision to intervene.78,81 Patients should have a stable systolic blood pressure greater than 90 mm Hg with a heart rate less than 100 beats/min after controlling other possible sources of extra-abdominal blood loss, such as orthopedic and soft tissue injuries. Failure from subsequent liver hemorrhage occurs in 0.4–5% of patients and failure due to missed injury of other intra-abdominal organs, such as the kidney, spleen, pancreas, and bowel, occurs in 0.5–15% of patients.75,76,79,81,82 These data are summarized in Table 12-8. It is difficult to tell the specific cause of immediate surgery in the earlier reports because laparotomies for all causes, such as associated splenic hemorrhage, were included. Christmas et al and Velmahos et al report that rates of immediate operative intervention for liver hemorrhage are 15 and 13%, respectively.78,79

Angiographic embolization is a useful adjunct in the management of blunt hepatic trauma both in nonoperative patients and those who have undergone damage-control laparotomy in a number of small series.78,79,83–89 Intravenous contrast extravasating from the liver parenchyma into the peritoneal cavity and contrast contained within the parenchyma of the liver associated with a large amount of intraperitoneal blood on initial CT scan are emergent situations mandating angiographic embolization or surgery.90 If bleeding appears to originate from the retrohepatic vena cava or hepatic veins and is ongoing, emergent exploration is the only choice because arterial embolization is ineffective in these scenarios. Patients with labile blood pressure and parenchymal injury may be better served with emergent exploration depending on the time necessary to assemble the angiography team. However, if angiography is readily available, favorable results have been obtained transporting patients to the angiography suite with ongoing resuscitation for arterial bleeding.86,91 Patients requiring significant resuscitation during a successful embolization procedure may still be at risk for abdominal compartment syndrome and should have bladder pressures monitored if they receive greater than 10 units of blood products.79,92

Patients with contrast extravasation contained within the liver parenchyma without significant associated hemoperitoneum are less worrisome but should probably undergo arteriogram for further assessment.90 A perceived contrast blush on CT scan is associated with bleeding identified at angiography in approximately 60% of patients.87 Arteriography in the absence of contrast extravasation will likely be a low-yield study. Patients requiring operative exploration of their liver wounds that have arterial bleeding from deep within the liver parenchyma may benefit from hepatic packing with radiolucent laparotomy pads and direct transportation to the angiography suite.83,84,88

Several complications can occur in the management of liver trauma, including biloma, hepatic necrosis, liver abscess, and gallbladder necrosis.85 Minimally invasive techniques can be successfully used to handle the majority of these complications. Biloma can occur after significant damage to the biliary tree. Patients may present with an ileus, abdominal pain, distention, or an abscess often with some degree of hyperbilirubinemia. Percutaneous drainage for localized collections will often control the leak and immediate symptomatology.87,88 Persistent bile leak will usually require an endoscopic retrograde cholangiopancreatography (ERCP) with biliary stent placement. Patients with hepatic duct or common bile duct injury may require hepatectomy or hepaticojejunostomy. Patients with generalized ascites may benefit from laparoscopic washout and placement of perihepatic drains followed by ERCP for persistent leak.78,88

Simple abscess can usually be managed with percutaneous drainage, unless significant hepatic necrosis simultaneously exists.88 Sterile liver necrosis may eventually resolve with expectant management but usually requires hepatic debridement when associated with infection. Patients who undergo embolization without surgery have approximately a 20% chance of developing infected necrosis, while patients who undergo laparotomy followed by hepatic artery embolization have an incidence of hepatic necrosis of over 80% in one series.85 Gallbladder necrosis occurs in approximately 20% of grades IV and V injury following nonselective embolization of the right hepatic artery.87 These patients usually present several days after injury with leukocytosis, hyperbilirubinemia, and abdominal pain. HIDA (hepatobiliary iminodiacetic acid) scan and a high index of suspicion may be necessary to differentiate this diagnosis from the others listed.

Operative Management

Bleeding from minor liver injuries (grades I and II) usually stops spontaneously, and surgical intervention is rarely required.75,81,93 Occasionally, patients may require exploration for other injuries after abdominal trauma in the presence of minor liver trauma. Nonbleeding liver injuries should be left alone. In the face of coagulopathy or hypothermia, minor hepatic injuries may present with persistent oozing. In such cases, topical hemostatic agents, with or without perihepatic packing, may be all that is necessary to stop the bleeding if the patient is being adequately resuscitated.

Major liver injuries (grades III–V) are more likely to bleed and require surgical intervention. Because grades IV and V liver injuries can present formidable technical challenges even in the hands of the most capable individuals, a variety of surgical techniques have been developed for their management.

Large liver wounds should be quickly inspected to get some idea about the degree of hemorrhage and then packed off initially. Anesthesia should be notified about anticipated blood loss and blood availability checked. Vital signs and resuscitation status should be reviewed. Bleeding should be contained with packing and direct pressure until anesthesia has had time to “catch up.” Remaining focused and well organized, as well as replenishing intravascular volume, is invaluable in the management of any trauma patient.

The most direct approach at this point is to remove the packing and visually inspect for bleeding vessels which can be individually ligated. Debridement of devitalized tissue using finger fracture technique will expose additional bleeding vessels which may have retracted into the surrounding parenchyma. If bleeding prevents adequate visualization of the surgical field, the next step should be vascular control of the portal triad (ie, the Pringle maneuver).93 This maneuver is easiest to perform for the person standing on the left of the patient. This individual places the fingers of the left hand into the foramen of Winslow and uses the thumb to palpate for the cord of tissue running into the caudal surface of the liver. Once this structure is suspected, its identity can generally be confirmed by appreciating the pulse in the hepatic artery. A hole is then created in the hepatoduodenal ligament using blunt finger dissection. A noncrushing vascular clamp can be applied or a ½-in. Penrose drain can be doubled, looped around the porta and cinched down with a Kelly clamp. We prefer the latter technique because it seems to be less obtrusive to further manipulation of the liver and may be less traumatic to the structures of the porta.

If a Pringle maneuver does not adequately decrease liver bleeding, concern for hepatic vein or retrohepatic caval injury should be entertained. Obtaining adequate exposure in deep liver wounds or in juxtahepatic caval injuries is of utmost importance. The falciform ligament is taken off the diaphragm posteriorly to the bare area. The right and left triangular ligaments are dissected with the cautery extension to the corresponding coronary ligaments. Further dissection of the coronary ligaments to the bare area will allow vigorous mobilization of the liver into the surgical field. Careful dissection of the bare area will allow access to the suprahepatic inferior vena cava. If the plane in the bare area is difficult to develop, a transverse incision in the diaphragm here will gain access to the pericardium and intrapericardial control of the inferior vena cava can be achieved.94 Total hepatic isolation can be achieved with a Pringle maneuver and vascular control of the infrahepatic, suprarenal inferior vena cava, and the suprahepatic intra-abdominal or intrapericardial inferior vena cava. The final step in this procedure is occluding inflow to the intra-abdominal aorta at the diaphragm while cardiac return from the lower body is eliminated. The physiologic stress of this technique may not be well tolerated in patients with severe shock and clamp times less than 20–30 minutes should be maintained.

Vascular shunts of the liver, otherwise known as atriocaval shunts, have been devised to circumvent impeding cardiac return when vascular isolation of the liver is desired.95 In this procedure, early recognition of juxtahepatic venous injury is essential and liver bleeding is temporarily contained with packing and direct pressure.96 A two-team approach is best; a median sternotomy is performed simultaneously while gaining vascular control of the infrahepatic suprarenal vena cava with a Rumel tourniquet. A Rumel tourniquet is also necessary around the intrapericardial inferior vena cava. A purse-string suture is placed in the right atrial appendage, and an opening is created in this structure. A 32F chest tube can then be directed from the atrium into the inferior vena cava. The Rumel tourniquets are applied. Before inserting the chest tube, an additional fenestration should be created approximately 3 in from the tapered proximal end. This opening will allow egress of the blood from the chest tube returning from the lower half of the body back into the heart. The proximal end of the chest tube protrudes from the right atrial appendage that is secured with the purse-string suture. The end of the chest tube is clamped or can be accessed with a Christmas tree adapter and used as a large-bore resuscitation line. Exploration of the retrohepatic cava is now possible. A number of institution-specific variations of this technique have been described, but we are unaware of any technique that has demonstrated improved results over Schrock's original description.97–99

The alternative to shunting grade V injuries is termed “direct exposure” popularized by Pachter and others.100–102 This technique consists of four basic principles: (1) manual compression and packing of the liver with vigorous resuscitation, (2) portal triad occlusion, (3) wide mobilization of the hepatic ligaments allowing for medial rotation of the liver and exposure of the retro hepatic cava, and (4) extensive finger fracture including normal liver parenchyma for direct vascular control of the injury.102 In one analysis of over 142 patients sustaining juxtahepatic venous injuries, 35 (24.6%) were managed without a shunt, resulting in a survival rate of 49%. The patients managed with a shunt had a survival rate of 19%.102 Suffice it to stay, unless there is a significant institutional experience with the shunt, direct exposure or total hepatic isolation alone may provide the best chance for patient survival for the occasional patient presenting with a grade V injury.

Lobar hepatic resection offers exposure of the involved hepatic veins and retrohepatic vena cava in grade V injuries but has largely fallen out of favor because of high associated mortality rates.96,103–106 The only current recommendation for this procedure is when the majority of the lobectomy occurred at the time of injury and the disrupted portion or lobe of liver has questionable viability. Selective hepatic artery ligation is another technique that has been employed to control arterial bleeding deep within the liver that cannot be easily identified or controlled through the liver wound.107–110 In this situation, if a Pringle maneuver greatly reduces the arterial bleeding, the artery to the respective lobe should be dissected out and occluded. If this maneuver maintains hemostasis, the vessel may be taken. A more recent option is to pack the patient with radiolucent laparotomy pads and take him/her for an arteriogram and possible embolization.83,84,88

Once patients with operative liver trauma sustain surgical hemostasis, they may become hypothermic and coagulopathic with bleeding occurring from nonsurgical sources, in particular the raw liver parenchyma. At this point, the liver and other sources of nonsurgical bleeding may be packed with laparotomy pads and a temporary abdominal closure performed.106,111–116 Patients can then be transported to the intensive care unit where they may be further resuscitated and warmed. Take back for removal of the packing, and debridement of devitalized liver may generally be undertaken safely in 24–48 hours. Omental packing of the liver defect originally described by Stone may reduce the incidence of bile leak and abscess formation.117

The Bowel

There is yet no place for nonoperative management of hollow viscus injury, and the nemesis of nonoperative management of blunt abdominal trauma is therefore the missed bowel injury and all its catastrophic consequences. Otherwise, most management is straightforward—debridement and primary repair for nondestructive injuries and resection with primary repair versus stomal formation for destructive injuries.

Radiographic Findings of Blunt Bowel Injury

There are two basic types of findings of bowel injury on CT scan: direct and indirect. Direct findings are usually straightforward if present and amount to extravasation of oral contrast (if administered) and free air, which have been reported to occur in 4 and 28% of the time, respectively. Little else can explain the first of these two entities, while free air from other sources such as extensive subcutaneous emphysema tracking through a diaphragmatic hiatus is unusual.118–120 Indirect findings may be subtle and can vary in presentation depending on the quality of the scan. Indirect findings include mesenteric hematoma or contrast blush, bowel wall edema, unexplained free fluid, “fat streaking” and bowel loops that don't opacify with intravenous contrast (Table 12-9).

Mesenteric hematoma is nonspecific and can occur from associated injuries, such as pelvic fractures or renal injuries with hematomas from these structures tracking into the bowel mesentery. However, a vascular blush in the leaves of the mesentery is indicative of active hemorrhage until proven otherwise and, generally, a determinant for immediate operative exploration. Bowel wall edema and ascites are common in blunt trauma patients, can occur from resuscitation of other injuries, and don't necessarily connote bowel injury. Free fluid in the absence of solid organ injury can be further evaluated with DPL if the abdominal examination is unreliable. Fat streaking can occur with mesenteric contusion and does not necessarily portend an operative indication. Unopacified bowel loops can indicate vascular disruption of the mesentery or simply be due to poor contrast timing in an under-resuscitated patient. In review of 8112 CT scans, Malhotra showed that at least one of these findings was present in 88.3% of patients with blunt bowel or mesenteric injury and that the likelihood of finding an injury at exploration increased when there was an increasing number of these findings.

Operative Management

Appreciation of the AAST organ injury grading scale is helpful in describing wounds of the bowel.121 Grade I injuries are contusions and partial-thickness lacerations of the bowel wall without perforation. Grade II injuries are full-thickness wounds involving less than 50% of the bowel wall circumference. Grade III are lacerations comprising greater than 50% of the bowel wall circumference without complete transaction. Grades IV and V injuries represent complete transection of the bowel wall and transection with segmental tissue loss and/or devascularization of the mesentery respectively. The terms destructive and nondestructive simplify the terminology; nondestructive wounds are those injuries that can be managed with debridement and primary suture enterorrhaphy and comprise grades I–III.122 Destructive wounds require resection of an entire segment of the bowel due to loss of colonic integrity or devascularization of the mesentery and encompass grades IV and V (Tables 12-10 and 12-11).

The distinction between destructive and nondestructive wounds is important in terms of the prescribed management. Nondestructive wounds of the large or small bowel can generally be repaired without further consideration. Most small bowel destructive injuries should be resected and reconstituted unless damage-control conditions prevail.

In contrast to the small bowel, the management of colon injuries has received great scrutiny. Ushering in the dawn of modern-day trauma surgery, the WWII military experience dictated that all colon wounds, destructive or not, be managed by colostomy. This philosophy remained surgical dogma until the 1980s.123,124 In a comprehensive review of the literature since 1979, primary repair of the colon for nondestructive wounds had been shown to have a leak rate of 1.6%.122 Compared to patients receiving colostomy for similar types of wounds, the incidence of intra-abdominal abscess was 4.9% for primary repair and 12% for colostomy, and overall complication rate was 14% for primary repair and 30% for colostomy. Mortality rates were similar at 0.11% for primary repair and 0.14% for colostomy. These findings clearly show the superiority of primary repair for nondestructive wounds of the colon.

Several risk factors for anastomotic failure pertaining to destructive colon injury have been addressed in the literature: hypotension, shock, interval from injury to operation, amount of fecal contamination, associated organ injury, transfusion requirement, and comorbid disease.125 No data have conclusively shown that any of these risk factors increase the likelihood of anastomotic failure with certain caveats. Patients with massive blood loss or shock may be better served by undergoing a damage-control procedure, with definitive repair delayed.126 Interval from injury to repair greater than 12 hours can be a relative contraindication, if there is wide-spread (greater than one quadrant) fecal contamination. Greater than one- or two-organ system injury has been a concern, but this may just be a marker for degree of shock and overall physiologic derangement. Comorbidities such as AIDS and cirrhosis deserve special consideration, and these patients may be better off with diversion.127,128 Aside from suture line failure, patients with any of these risk factors have a higher incidence of intra-abdominal abscess and overall complications rates.122

Not withstanding the risk factors for colon trauma, most series regard resection and primary anastomosis for destructive colon wounds in a favorable light. In a collective review of 207 patients reported in the literature, management of destructive bowel injury with resection and primary anastomosis had a reported leak rate of 7.2% with a mortality of 1.7% attributable to the colon wound.122 In the largest single institution experience, Murray showed a leak rate of 11% in 112 patients undergoing resection and primary anastomosis for destructive colon wounds with two deaths related to leaks.129

In a multi-institutional trial, Demetriades reported 297 patients with destructive colon wounds in which 197 underwent resection and anastomosis and 100 underwent diversion.127 The choice of operation was left to the discretion of the attending surgeon at the time of exploration. Not surprisingly, the patients with diversion were significantly more injured and ill than those being reconstituted. The anastomotic leak rate was 6.6%, with one leak from the stump of a Hartmann's pouch in the diverted group and four deaths related to anastomotic failure. Multivariate analysis showed no significant difference in mortality or abdominal complications between diversion and primary anastomosis groups. The authors concluded that “patients can be managed by primary repair regardless of risk factors.” This study certainly demonstrates a liberal use of resection and primary anastomosis in a relatively sick and injured cohort of patients. However, the ultimate decision for the choice of operation was up to the discretion of the surgeon at the time of operation, for which there is no substitute.

At laparotomy, the bowel should be examined in its entirety after all other sources of major bleeding are controlled. Small injuries should be noted and tagged with an identifiable suture for easy reference. Larger wounds contributing to ongoing soiling can be temporarily controlled with a “whip stitch” (quick running suture) or Babcock clamps. Mesenteric injuries are identified and active bleeding controlled appropriately. Attention should be directed to the location of the superior mesenteric artery for injuries encroaching on the root of the mesentery. Mesenteric hematomas should be explored with ligation of injured vessels and mesenteric defects closed by careful reapproximation of the peritoneal edges so as not to compromise any feeding vessels. Bowel viability should be noted in relation to any mesenteric injury. Clusters of grade I through III injuries may be resected or individually repaired depending on the particular injury pattern. In blunt trauma, there is usually only one or two grade II or III wounds that can be repaired primarily or one or more devitalized segments that require resection.

Small, superficial grade I injuries can be left alone while deeper, longer grade I injuries can be closed with a simple running suture or interrupted Lembert sutures. Grades II and III wounds should be debrided back to healthy, viable bowel and closed transversely preventing narrowing of the lumen of the bowel. Single layer running or interrupted closure is generally sufficient for repair of the small bowel. When there is significant bowel wall edema, peritonitis or soiling, a two-layer closure with a running inner layer and interrupted Lembert outer layer may be preferential. Grades I and II colon wounds may be managed with single layer closure, but we usually close grade III colon wounds in two layers for added protection.

The leak rate associated with stapled versus hand-sewn anastomosis for destructive wounds of the bowel has been an area of controversy. In two retrospective studies totaling 284 patients undergoing stapled versus hand-sewn anastomosis, Brundage et al showed that hand-sewn procedures had lower leak rates.130,131 Two other retrospective studies totaling 484 patients showed no difference in the leak rate of stapled versus hand-sewn procedures.132,133 Brundage's two studies included 78 colon wounds while the other studies were confined only to the small bowel. Stapled procedures may be a little quicker, particularly if there is more than one anastomosis. In general, the technique chosen according to the literature can be a matter of personal preference. With edematous bowel, the hand-sewn technique is a more prudent approach.

In addition to the management of abdominal trauma that has been underscored throughout the chapter for both penetrating and blunt trauma, there are several proposed treatment paradigms for many of the injuries sustained in trauma. However, the standard-of-care management for an individual is heavily dependent on the resources and personnel available, along with transport options, if any. There are resource-rich trauma systems throughout the country, with highly qualified personnel. However, these systems are not uniform throughout the nation, and the concept of regionalization has not been perfected for all the regions in the country. The overarching goal remains the same: optimal management for everyone, irrespective of where the patient receives trauma care.