An acute upper airway obstruction is a blockage of the upper airway, which can be in the trachea, laryngeal (voice box), or pharyngeal (throat) areas.

Acute upper airway obstruction may have any of a number of causes including viral and bacterial infections, fire or inhalation burns, chemical burns and reactions, allergic reactions, foreign bodies, and trauma. The blockage can be complete or partial. Mild obstruction may result in air hunger, while more severe obstruction can lead to cyanosis (a bluish discoloration of the skin or mucous membranes caused by lack of oxygen in the blood), confusion, or unconsciousness. Complete obstruction, if not corrected, leads to rapid suffocation and death.

Symptoms of acute upper airway obstruction are dramatic and easy to diagnose. The individual may suddenly begin having difficulty breathing or be unable to breathe at all. Cyanosis, unconsciousness, and death may rapidly follow a large or total obstruction.

Common causes of acute upper airway obstruction include:

• Foreign bodies -- In adults, foreign bodies are usually inhaled bits of food. In children, peanuts are the most commonly inhaled food, but hot dogs are the most common food item associated with choking deaths, because of their size and shape. Children also commonly choke on many nonfood items, such as balloon fragments, buttons, coins, and small toys.
• Acute allergic reactions in which the trachea or throat swell closed are a common cause of airway obstruction. The classic example is an allergic reaction to a bee sting, which frequently takes the form of an anaphylactic reaction. Other common causes include allergy reaction to peanuts, antibiotics (penicillin), and blood pressure medications (ACE inhibitors).
• Croup may lead to a fairly rapid decrease in airway diameter and marked respiratory distress.
• Epiglottitis can cause rapid airway obstruction as the epiglottis swells and occludes the airway.
• Retropharyngeal abscess is a rapidly expanding abscess can block the airway and cause respiratory distress.
• Peritonsillar abscess is similar to retropharyngeal abscess.

Symptoms vary depending on the cause, but some symptoms are common to all types of obstruction.

• Choking
• Gasping for air
• Wheezing, crowing, whistling, or other unusual breathing noises indicating breathing difficulty
• Agitation or fidgeting
• Panic
• Cyanosis
• Changes in consciousness
• Unconsciousness

Physical examination may show decreased breath sounds. Tests are usually not necessary, but may include x-rays, bronchoscopy, and laryngoscopy.

If the victim has a complete obstruction and is unable to speak or breathe, the Heimlich maneuver may be lifesaving. Treatment depends on the cause of the blockage. Objects lodged in the airway may be removed with a laryngoscope or bronchoscope. A tube may be inserted into the airway (endotracheal tube or nasotracheal tube). Sometimes an opening is made directly into the airway (tracheostomy or cricothyrotomy).

Prompt treatment is often successful. However, the condition is dangerous and may be fatal, even if treated.

Inability to relieve the obstruction can cause breathing failure, brain damage, or death.

Airway obstruction is an extreme emergency. It is a good idea to learn to clear an airway of a foreign body by using a method such as the Heimlich maneuver. Diseases in which airway obstruction develops over a period of hours will allow time to get to a hospital. If an acute airway obstruction occurs, call 911 or your local emergency number for medical help, and use what knowledge and materials you have to maintain breathing until medical help arrives.

Prevention is dependent on the cause of the upper airway obstruction. See the individual diseases in the above section for more information.