Air enters the body through the nose and mouth. The nose cleans, warms and humidifies inspired air. Air entering the mouth is less effectively cleaned. Inspired air then travels through the pharynx (throat) and enters the trachea.

The pharynx spits into two tubes, the trachea in the front and the esophagus in the rear. Breathing and swallowing compete for the pharyngeal space. If food is inhaled by mistake, the airway is blocked. Vigorous coughing can clear the airway, but a stubborn obstruction can end life unless a good Samaritan intervenes with the Heimlich maneuver. By vigorously compressing the upper abdomen, air is forced from the lungs. In the best case, a tracheal obstruction is cleared. As long as food and beverages move to the rear and descend in the esophagus, the airway remains secure.

In emergency medicine the upper airway is the first concern. You learn to assess and clear the airway of a patient first, then confirm breathing, then confirm cardiac status-- check heart beat and blood pressure.  The airway can be obstructed in many ways and must be clear before a life can be saved. Securing the airway is done with suction to clear liquids that accumulate in the pharynx and by plastic tubes that connect the outside air with the trachea. If the upper airway is damaged or cannot be secured. A tube is inserted into the trachea below the larynx to allow air flow directly into the lungs.  

Learn more about ear nose and throat disorders by clicking links on the left.