Annually in the United States more than 300 deaths of children are due to choking secondary to upper airway obstruction (1). These incidents are usually due to foods, toys, or other small objects. More than 90% occur in infants and children younger than 5 years of age and 65% in infants younger than 2 years of age. Foods continue to be the most common objects involved in reported choking episodes in the infant and the child, with round or cylindrical foods most often cited (2) (Table 51.1).

In 1979, the U.S. Consumer Product Safety Commission passed regulations to control the marketing of nonfood choking hazards (3). Small toys, rubber balloons, nails, tacks, and bolts are the main objects responsible for nonfood-related choking episodes in children (4,5,6,7,8,9). Rubber balloons are the leading cause of choking deaths from toys. Of these deaths, 75% are in children under 6 years of age (10).

Treating the child with an acutely obstructed airway is an emergent procedure. Although usually performed in the prehospital setting, it may be necessary to perform the procedure in the emergency department (ED). The first-aid approach is routinely taught to the lay public by emergency medicine and other health care providers. The laryngoscopic procedure may be performed by any qualified physician.

The nose, mouth, and pharynx comprise the upper airway. The upper airway has numerous functions, which include acting as a filter to prevent foreign material from entering the lower airway, humidifying and heating inspired gases, and acting as a system for conducting inspired gases to the lungs.

Ciliated and nonciliated mucous cells line the nose. The function of these cells is to help humidify inspired gases and to filter foreign material. Hair follicles and thick, sticky mucous secretions of the nose also help filter foreign material from the upper airway.

The laryngopharynx extends from the base of the tongue to the esophagus, which lies posterior to the trachea. Closure of the glottis protects the tracheobronchial tree from foreign material. This reflex mechanism is crucial in protecting the airway during the process of swallowing. Patients with neuromuscular illness, anatomically abnormal airways, or poorly protected airways are at the highest risk for foreign body aspirations and choking episodes.

The trachea begins at the level of the cricoid cartilage; it descends in the middle of the neck to the level of the fifth to sixth thoracic vertebra and then bifurcates into the right and left mainstem bronchi. Unlike in adults, the angle of takeoff at the carina is almost equal on both sides in young children. In the older child and young adult, the trachea at the bifurcation
is slightly angled to the right, making the opening to the right bronchus a less acute angle.

The airway has protective mechanisms in place that continuously remove foreign debris. Tiny foreign bodies are continually swept up by cilia and mucus to the supraglottic region, where they can be swallowed down the esophagus. Coughing, which results from stimulation of receptors in the mucosa of the large respiratory passages, is an important means of expelling secretions and foreign matter from the airway. A cough begins with a deep inspiration followed by a forced expiration against a closed glottis. The glottis is then suddenly opened, producing a forceful outflow of air.

Four assumptions form the rationale for the current recommended treatment of acute airway obstruction in infants and children (11). First, airway obstruction with secondary cardiac arrest is far more common in pediatric patients than the sudden cardiac arrest with secondary airway obstruction seen in adults. Second, a foreign body completely obstructing the upper airway is an immediate threat to life and must be removed. Third, if the child can speak, breathe, or cough, the foreign body is only partially obstructing the airway, yet it may be dislodged or moved to a position that totally obstructs the airway. This can make first-aid airway maneuvers potentially dangerous. Finally, partial airway obstruction with poor air exchange or complete airway obstruction with cyanosis requires immediate relief.

Importantly, any child who has choked on a foreign body but who is coughing, crying, or speaking should merely be observed, at least initially, since the normal airway reflexes will likely be sufficient to fully clear the obstruction. However, if acutely worsening or complete obstruction develops, if the child or infant is unable to make sounds, or if there is no evidence of respiratory air movement, immediate first aid to establish a patent airway and deliver basic life support is required to avoid permanent disability or death (12).

The abdominal-thrust (Heimlich) maneuver is thought to be the most effective method of relieving complete airway obstruction in children over 1 year of age (13). This method is based on several physiologic factors: (a) 80% of respiratory effort is from diaphragmatic contraction; (b) abdominal inward pressure compresses the diaphragm upward, thereby raising intrathoracic pressure; (c) a sudden, rapid increase in intrathoracic pressure may expel the obstructing object; and (d) patients with airway obstruction who become unconscious from hypoxia lose muscle tone, which improves the effectiveness of the maneuver (13). If the abdominal-thrust maneuver is initially ineffective, continued attempts using this method should be made, as it may prove successful after the patient loses consciousness (12).

The American Academy of Pediatrics (AAP), the American Heart Association (AHA), and the Red Cross all recommend that the abdominal-thrust maneuver be used in children over 1 year of age for complete airway obstruction. Some controversy exists, however, about which maneuver—the abdominal thrust or the combination back blow and chest thrust—is best for the choking patient under 1 year of age. In infants, the stomach, liver, and spleen are relatively larger than they are in older children. Damage and even rupture of abdominal organs with the abdominal-thrust technique have been reported (14,15). Additionally, infants have greater chest wall compliance than older children. A compliant chest wall absorbs some of the energy from the abdominal-thrust maneuver by allowing increased chest wall expansion, which in turn decreases the extent of lung and airway compression. This can make the abdominal-thrust maneuver less effective in producing pressure changes adequate to expel a foreign object from the obstructed airway.

For infants under 1 year of age, the technique currently recommended by the AAP and AHA involves two steps: the head-down back-blow maneuver and the chest-thrust maneuver (12). The head-down back-blow maneuver is designed to compress the chest with a posteriorly applied force while the anterior chest is held. Ideally, this will generate a rapid increase in intrathoracic pressure that propels the foreign body out of the airway (16). Similarly, the chest-thrust maneuver uses sternal compression to increase intrathoracic pressure in an effort to expel the foreign object. This maneuver is much like performing chest compressions in the setting of cardiopulmonary arrest.

A concern has been raised that the sudden acceleration produced by the back-blow maneuver in an awake patient may actually worsen airway obstruction. Back blows in an awake patient might stimulate inhalation at the same time as the pressure is increased, possibly opening the airway and allowing the foreign body to advance in the wrong direction. Some evidence has indicated that the back-blow maneuver may in fact cause caudal movement of the object, in concordance with Newton’s third law of motion: to every action there is an opposed equal reaction (17). Nevertheless, it appears that, in
the case of an infant, when the maneuver is performed with the infant held head down and prone over the rescuer’s leg (Fig. 51.1), further intrusion of the foreign body is unlikely(12).