Foreign Bodies in the Airway
Allison R. Hammer, James W. Schroeder Jr
Epidemiology and Etiology
Choking is a leading cause of morbidity and mortality among children, especially those younger than 4 yr of age. Most victims of foreign body aspiration are older infants and toddlers (Fig. 414.1 ); males have been found to be victims up to 1.7 times more likely than females. Studies show that children younger than 4 yr of age account for 61.7–70% of airway foreign body cases. The most common objects on which children choke are food items (59.5–81% of all choking cases). Nuts, seeds, hot dogs, hard candy, gum, bones, and raw fruits and vegetables are the most frequently aspirated food items. From 2001 to 2009, an average of 12,435 children ages 0-14 yr in the United States were treated in emergency departments for choking on food without fatality. Common inorganic objects on which children choke include coins, latex balloons, pins, jewelry, magnets, pen caps, and toys. Globular, compressible, or round objects such as hot dogs, grapes, nuts, balloons, marshmallows, meats, and candies are particularly hazardous due to their ability to completely occlude the airway.
Young children are more at risk to aspirate a foreign body largely because of their developmental vulnerabilities and their underdeveloped ability to swallow food. Infants and toddlers often use their mouths to explore their surroundings, and children generally are more likely to be distracted, playing, or ambulatory while eating. An infant is able to suck and swallow and is equipped with involuntary reflexes (gag, cough, and glottis closure) that help to protect against aspiration during swallowing. Dentition develops at approximately 6 mo of age with the eruption of the incisors. Molars do not erupt until approximately 1.5 yr of age; mature mastication takes longer to develop. Despite a strong gag reflex, a child's airway is more vulnerable to obstruction than an adult's airway. Young children are more likely to experience significant blockage by small foreign bodies due to their smaller airway diameter. Mucus and secretions may form a seal around the foreign body, making it more difficult to dislodge by forced air. In addition, the force of air generated by an infant or young child's cough is less effective in dislodging an airway obstruction. It is recommended that children younger than 5 yr of age should avoid hard candy and chewing gum and that raw fruits and vegetables be cut into small pieces. Other factors, such as developmental delays or disorders causing neurologic or muscular issues, can also put children at higher risk for foreign body aspiration.
Clinical Manifestations
Foreign bodies of the airway have variable presentations and complications, depending on the characteristics, duration, and location of the foreign body. The clinical manifestations range from an asymptomatic state to severe respiratory distress. The most serious complication of foreign body aspiration is complete obstruction of the airway, which may be recognized in the conscious child as sudden respiratory distress followed by an inability to speak or cough.
There are typically three stages of symptoms that result from aspiration of an object into the airway:
- 1. Initial event: Paroxysms of coughing, choking, gagging, and possibly airway obstruction occur immediately after aspiration of the foreign body. The child is sometimes able to expel the foreign body during this stage.
- 2. Asymptomatic interval: The foreign body becomes lodged, reflexes fatigue, and the immediate irritating symptoms subside. The lack of symptoms can be particularly misleading to the provider when a child presents in this stage and accounts for a large percentage of delayed diagnoses and overlooked foreign bodies . A large meta-analysis of more than 30,000 patients showed that diagnosis is delayed more than 25 hr in almost 40% of airway foreign body cases.
- 3. Complications: Obstruction, erosion, or infection develops, which again directs attention to the presence of a foreign body. In this third stage, complications include fever, cough, hemoptysis, pneumonia, and atelectasis. Acute or chronic complications have been reported in almost 15% of cases of foreign bodies of the airway.
Diagnosis
History is the most important factor in determining the need for bronchoscopy. A positive history must never be ignored, but a negative history can be misleading. Because nuts and seeds are the most common bronchial foreign bodies, the physician should specifically question the child's parents about these items, and bronchoscopy should be carried out promptly. A comprehensive physical exam is also essential, including examination of the nose, oral cavity, pharynx, neck, and lungs. Choking or coughing episodes accompanied by new-onset wheezing and asymmetric breath sounds are highly suggestive of foreign body in the airway. In addition to history and physical examination, radiology studies have an important role in diagnosing foreign bodies in the airway. Plain films are typically recommended first, although many foreign bodies are radiolucent (80–96%), and therefore providers often must rely on secondary findings (such as air trapping, asymmetric hyperinflation, obstructive emphysema, atelectasis, mediastinal shift, and consolidation) to indicate suspicion of a foreign body. Expiratory or lateral decubitus films can assist in revealing these suggestive secondary findings. The indication for computed tomography of the chest is currently being explored due to its high sensitivity and specificity, its ability to detect radiolucent objects, and its potential to eliminate the need for an anesthesia and procedure. However, the known risks of radiation must certainly be considered. If there is a high index of suspicion despite negative or inconclusive imaging, bronchoscopy should be performed.
Treatment
The treatment of choice for airway foreign bodies is prompt endoscopic removal with rigid instruments by a specialist (otolaryngologist or pulmonologist). Bronchoscopy is deferred only until providers have obtained preoperative studies and the patient has been prepared by adequate hydration and emptying of the stomach. Airway foreign bodies are usually removed the same day the diagnosis is first considered. As with any treatment modality, providers must give careful consideration to the risks and benefits of the bronchoscopy procedure when diagnosis is unclear. Potential complications of rigid bronchoscopy include bronchospasm, desaturation, bleeding, and airway edema, in addition to the inherent risks of anesthesia.
Beyond the understanding of diagnosis and management of airway foreign bodies, there is a strong need and push for awareness, education, and prevention among caregivers, healthcare providers, and manufacturers of food and toys.
Laryngeal Foreign Bodies
Allison R. Hammer, James W. Schroeder Jr
Although laryngeal foreign bodies are less common (2–12% of cases) than bronchial or tracheal foreign bodies, they are particularly dangerous due to risk of complete laryngeal obstruction, which can asphyxiate the child unless it is promptly relieved with the Heimlich maneuver (see Chapter 81 and Figs. 81.6 and 81.7 ). Objects that are partially obstructive of the larynx are usually flat and thin and lodge between the vocal cords in the sagittal plane, causing symptoms of croup, hoarseness, cough, stridor, and dyspnea.
Tracheal Foreign Bodies
Allison R. Hammer, James W. Schroeder Jr
Tracheal foreign bodies account for 3–12% of airway foreign body cases. Children who have tracheal foreign bodies can present with dysphonia, dysphagia, dry cough, or biphasic stridor. Posteroanterior and lateral soft tissue neck radiographs (airway films) are abnormal in 92% of children, whereas chest radiographs are abnormal in only 58% of these cases.
Bronchial Foreign Bodies
Allison R. Hammer, James W. Schroeder Jr
Most airway foreign bodies lodge in a bronchus (80–90% of cases). Occasionally, fragments of a foreign body may produce bilateral involvement or shifting infiltrates if they move from lobe to lobe. Some children with bronchial foreign bodies present asymptomatically, whereas others have asymmetric breath sounds, coughing, and wheezing. Posteroanterior and lateral chest radiographs (including the abdomen) are standard in the assessment of infants and children suspected of having aspirated a foreign object. An expiratory posteroanterior chest film is most helpful. During expiration, the bronchial foreign body obstructs the exit of air from the obstructed lung, producing obstructive emphysema and air trapping. The persistent inflation of the obstructed lung causes shift of the mediastinum toward the opposite side (Fig. 414.2 ). Air trapping is an immediate complication, whereas atelectasis is a late finding. Lateral decubitus chest films or fluoroscopy can provide the same information as expiratory films but are often unnecessary. History and physical examination, not radiographs, determine the indication for bronchoscopy.
