Introduction

Choking emergencies are important in EMS because of their time-sensitive nature. Victims of choking can rapidly progress from airway obstruction to loss of consciousness and cardiac arrest. Bystanders must act quickly to resolve true choking episodes. EMS personnel will likely arrive on scene several minutes after the onset of choking. Therefore, they must be prepared to manage a patient in the advanced stages of crisis. Choking is an emergency that must be solved on scene; there is limited value in bringing an unresolved choking victim to the emergency department for definitive treatment.

Pathophysiology and epidemiology

Choking results from obstruction of the trachea by a foreign object. It is the nature of the so-called “café coronary” that occurs during or shortly after a meal [1]. Although most choking episodes are associated with food, non-edible objects may also cause airway occlusion; particularly, children may inadvertently aspirate coins, toys, or other objects. Choking can occur with liquids as well as solid substances.

Although most obstructions occur in the hypopharynx, a small foreign body may lodge in either bronchus, causing selective obstruction of a lung or lung segment. Because the right bronchus travels more directly off the trachea, most selective obstructions involve the right lung.

Choking may be classified as partial or complete. A complete obstruction impairs the ability to breathe, to talk, and to cough and is an immediate life threat. A partial obstruction results in incomplete occlusion of the airway. In these instances the individual may still be able to breathe, talk, or cough. A complete occlusion generally mandates immediate intervention (such as the Heimlich maneuver, or direct laryngoscopy if ALS personnel are present). Other less invasive maneuvers may be appropriate in individuals with partial obstruction. However, in instances of partial obstruction with compromised air exchange, cyanosis, or loss of consciousness, the rescuer must approach the case as though it involves a complete airway obstruction [1].

The incidence of choking varies with age. Children younger than 1 year of age are most likely to choke, with food and liquids causing most of these episodes. Toddlers aged 1–4 years tend to choke on non-food items such as coins or latex balloons. Choking is less common in those aged 4–9 years and often occurs from gum and candy [2,3].

Choking incidence rises again at age 60 years from concurrent conditions impairing coordinated swallowing (e.g. Alzheimer dementia, stroke, drinking alcohol, seizure, or Parkinson disease) [4]. A prior choking episode significantly increases the chances of future choking.

Patient assessment

Because complete or partial airway obstruction may rapidly lead to cardiopulmonary arrest, expeditious recognition of choking is essential. Ideally, bystanders will recognize and immediately treat choking victims. Delay of recognition and treatment until EMS arrival will likely result in clinical deterioration. Patients suffering from complete airway obstruction usually present with classic signs, including aphonia, hands to the throat, and hyperemia of the face. Other more serious signs include altered mental status, cyanosis, and unconsciousness. Many conscious choking victims will exhibit the universal choking sign (hands crossed over the throat) and will nod in affirmation to the question, “Are you choking?” [5]

Partial airway obstruction may be more difficult to assess, especially in pediatric patients. These individuals may still have partial speaking ability. In many cases, the victim may exhibit paroxysmal coughing, drooling, stridor, or poor feeding. Common conditions mimicking foreign body aspiration include pneumonia, asthma, croup, and reactive airway disease [6,7]. An esophageal foreign body may also cause or mimic airway obstruction. Vital signs, pulse oximetry, and other diagnostic tools are not typically useful in establishing the severity of a choking episode. In one series, 2% of admitted adult choking patients had normal prehospital vital signs [8].