Chapter 39. Foreign Bodies

• SFABL: Patient history
• Witnessed ingestion and history of choking
• High level of clinical suspicion
• Respiratory and swallowing symptoms
• Posteroanterior and lateral neck and chest films are diagnostic

Foreign body ingestion and aspiration are an important cause of morbidity and mortality in the pediatric population. Aerodigestive tract foreign bodies are the cause of approximately 150 pediatric deaths per year in the United States, and choking causes 40% of accidental deaths in children less than 1 y of age. Foreign bodies remain a diagnostic challenge as their presentation can vary from life-threatening airway compromise to subtle respiratory symptoms that are often misdiagnosed. A high level of clinical suspicion can prevent delays in diagnosis and complications related to these delays.

Most aerodigestive tract foreign bodies occur in children under the age of 4 y. The high incidence of aerodigestive foreign bodies in children of this age is related to their increased mobility, the introduction of adult food, a high propensity for placing objects in their mouths, incomplete dentition, and immature swallowing coordination. Other populations at risk for esophageal foreign bodies include psychiatric patients, patients with underlying esophageal or neurological disease, and edentulous adults. Coins are the most commonly ingested foreign body, whereas nuts and seeds are the most commonly aspirated foreign body (Figure 39–1). Although fortunately rare, the aspiration of latex balloons is associated with especially high mortality rates. In older children and adults, fish or chicken bones may lodge in the oropharynx.

Damage to the surrounding aerodigestive tract mucosa is related to the type of foreign body and the length of time the foreign body has been present. Granulation tissue formation, erosive lesions, and infections can occur over time and can be minimized with early diagnosis and surgical intervention.

The prevention of ingestion is the most important intervention for potential aerodigestive tract foreign body ingestions. The Consumer Products Safety Act was passed in 1979 and includes criteria for the minimum size of objects >3.17 cm in diameter and >5.71 cm in length) allowable for children to play with, but these regulations are not uniformly enforced. Young children should remain under constant adult supervision and allowed to play only with age-appropriate toys. Small and hazardous objects should be safely stored so as not to be accessible to a newly mobile and curious child. Food should be age appropriate and presented only in an observed setting.

Children with esophageal motility disorders or neurological disorders should be encouraged to chew food slowly and completely to avoid esophageal impactions or aspiration.

Symptoms and Signs

A witnessed ingestion or aspiration episode should be brought to the attention of a physician. Information that is important to elicit from parents includes the approximate time of ingestion, any history of esophageal dysfunction, and both the severity and the duration of swallowing and respiratory symptoms since the time of ingestion. When an unusual foreign body is aspirated or ingested, it may also be helpful to have the parents bring in a similar object from home.

Typical signs and symptoms of esophageal foreign body ingestion include drooling, dysphagia, emesis, food refusal, and chest pain. Esophageal foreign bodies may also cause respiratory symptoms in a young child. Airway foreign bodies may initially present with an episode of choking, gagging, and cyanosis followed by coughing, wheezing, and/or stridor. Physical examination may reveal asymmetric breath sounds or unilateral wheezing. However, the patient can become asymptomatic when the foreign body lodges more distally in the airway. This can make diagnosis difficult, especially when the initial event is unwitnessed. A high index of suspicion should be maintained when evaluating children presenting with a sudden onset of respiratory symptoms or with recurrent croup, asthma, or pneumonia without the expected response to treatment.

Imaging Studies

Posteroanterior and lateral plain films of the neck and chest are the imaging studies of choice. Radiopaque foreign bodies should be straightforward to diagnose, whereas other foreign bodies may be more difficult. Unilateral hyperinflation, localized atelectasis or infiltrates, mediastinal shift, and esophageal air trapping can all be clues to the presence of a foreign body even when no foreign body is visualized. (Figure 39–2). Both posteroanterior and lateral views should be obtained as they can help differentiate between esophageal and tracheal foreign bodies and provide clues as to the type of foreign body. For example, button batteries have a characteristic double contour on lateral view but may be mistaken for coins on posteroanterior views.

Imaging studies should not be used to rule out the presence of a foreign body. High clinical suspicion or historical evidence (ie, witnessed ingestion or aspiration) warrants rigid endoscopy even if imaging studies are normal. If plain films are not diagnostic or the patient cannot cooperate for the imaging exam, airway fluoroscopy is sometimes used. This study has the added advantage of demonstrating a dynamic view of the airway; however, it is dependent on the expertise of the radiologist performing the examination. Barium swallow is generally not indicated, and the presence of barium can make esophageal foreign body extraction more difficult.

The differential diagnosis of aerodigestive tract foreign body is generated in part using presenting symptoms, but it is more dependent on the history obtained from parents or other caregivers. As previously mentioned, children with esophageal foreign bodies may present with airway symptoms or symptoms mimicking nonspecific gastrointestinal illness. These children may be misdiagnosed with pharyngitis or gastroenteritis.

Bronchial foreign bodies may present with chronic cough or wheezing. Common misdiagnoses include asthma, croup, and pneumonia. In children with these diagnoses who continue to seek medical attention and do not appear to respond to appropriate treatments, the presence of an airway foreign body should be considered.

Complications from aerodigestive tract foreign bodies result from both the type of foreign body and the duration of entrapment. Objects such as button batteries can cause mucosal erosion in as little 6 hours from the time of ingestion. The risk for complications increases with the duration of time the foreign body remains in place. The initial complications from a laryngeal or bronchial foreign body can be severe, including cyanosis, respiratory distress, and even respiratory arrest and death. A ball-valve effect can occur with a partially occluding bronchial foreign body causing hyperexpansion of the affected lung. If complete bronchial occlusion is present, total or partial lung collapse can occur. Late complications of bronchial foreign bodies include granulation tissue formation, pneumonia, empyema, bronchial fistula, and pneumothorax. In the case of esophageal foreign bodies, late complications include granulation tissue formation, mucosal erosions, esophageal perforation, tracheoesophageal fistula, esophageal-aortic fistula, and mediastinitis.

The treatment of choice for aerodigestive tract foreign bodies is rigid endoscopic removal under general anesthesia. This is carried out in the operating room with proper pediatric endoscopic equipment and pediatric anesthesiologists. Rarely, an oropharyngeal foreign body in an older, cooperative child, such as a fishbone impaling the tonsil, may be successfully extracted when the patient is awake.

Alternate methods of removal (eg, Fogarty catheters or flexible endoscopes) have been used in the past, but are generally not recommended because of the difficulty in protecting the airway or adequately controlling the foreign body with these methods. Meat tenderizers, muscle relaxants, and promotility agents have been used in the past for esophageal foreign bodies in adults, but no evidence supports their use in pediatric patients.

Most surgeons agree that an airway foreign body should be addressed at the time of presentation. Rapid sequence techniques may be preferred if aspiration of stomach contents is a concern. The timing of esophageal foreign body removal can be debated based on the type and location of the foreign body, the elapsed time since ingestion, and patient's age. An asymptomatic older child with a distal or midesophageal coin present for less than 24 hours and no history of esophageal disorders may be observed for a period of 8–16 hours to see if the coin will pass. Spontaneous coin passage rates range widely from 9% to 77% in this patient population. In young children, foreign bodies present for longer than 24 hours, sharp metallic or caustic foreign bodies (button batteries), and symptomatic patients (respiratory symptoms, discomfort, pooling, or intolerance of oral secretions) should not be observed for spontaneous passage. A child with a suspected disc battery ingestion requires urgent removal in the operating room to avoid mucosal erosion or perforation.

All equipment should be assembled and connected to appropriate light sources and video equipment before the patient enters the operating suite. The operating surgeon should be gloved and in position before induction, and the plan for induction should have already been discussed between the surgeon and the anesthesiologist. During endoscopic removal in the operating room, communication with the pediatric anesthesiologist is paramount. During manipulation, a stable esophageal foreign body can become an unstable tracheobronchial foreign body, or a partially obstructing bronchial foreign body can become an obstructing laryngeal foreign body. The otolaryngologist and anesthesiologist must be in constant communication to anticipate the patient's developing respiratory status.

Esophageal foreign bodies should be removed via rigid esophagoscopy with the patient intubated for airway protection. The esophagoscope may be introduced with the help of a laryngoscope or under direct vision. The esophagoscope should never be forced, but should be gently advanced, taking care to have the lumen centered in the field of vision. Once the foreign body has been identified, extraction may require removing the entire telescopic forceps and the esophagoscope complex. Care should be taken to avoid accidental extubation by having the anesthesiologist manually secure the endotracheal tube during removal of the esophagoscope. At least one more pass of the esophagoscope should be performed to check for multiple foreign bodies or mucosal damage. A notation of the distance from the esophageal inlet to any signs of mucosal damage should be recorded.

If the foreign body is removed easily without mucosal trauma, the child can be extubated and discharged from the recovery room if he or she is able to take adequate oral intake. If the foreign body has been present for an unknown length of time and there are signs of mucosal damage, the patient may require a longer period of observation postoperatively. Dexamethasone (ie, Decadron) at a dose of 0.5–1.0 mg/kg intravenous may be given if significant edema is present. A chest x-ray should be performed if there is evidence of a traumatic extraction and any concern of significant mucosal damage to rule out perforation and mediastinal air.

Airway

Airway foreign bodies should be retrieved with the patient spontaneously breathing. This facilitates the passage of a bronchoscope, prevents distal migration of the foreign body during positive pressure ventilation, and takes advantage of the natural increase in tracheal and bronchial cross-sectional area during inspiration. Paralytics should be avoided. After mask induction with an inhalational agent, topical lidocaine should be used to anesthetize the vocal folds. Direct laryngoscopy is performed and a rigid bronchoscope is introduced under direct vision. Once the bronchoscope has been introduced, the anesthesiologist may connect to the ventilation port. The foreign body is identified, secured, and removed. Removal may require withdrawing, as a unit, the telescopic forceps and bronchoscope (Figure 39–3). Care should be taken to avoid premature release of the foreign body as this can result in an obstructing laryngotracheal foreign body. The surgeon should also communicate with the anesthesiologist to confirm the depth of anesthesia so as to avoid laryngospasm upon withdrawal of the bronchoscope. Nuts and other foods may require multiple passes. Care should be taken to minimize mucosal trauma. Prior to completion, at least one more pass should be performed to evaluate for multiple foreign bodies and mucosal damage. Depending on the ease of extraction, the child may require a postoperative chest x-ray and close follow-up to rule out the development of pneumonia.

Most children make a full recovery without permanent sequelae from aerodigestive tract foreign body ingestion. Delays in the diagnosis cause the most severe morbidity. Children who have a delayed or technically difficult extraction should be observed postoperatively in an inpatient setting until they no longer require airway support or can tolerate an age-appropriate diet.