Airway obstruction: Partial or complete blockage of the breathing passages to the lungs. Causes include the presence of foreign matter, allergic reactions, infections, anatomical abnormalities, and trauma. Associated respiratory distress may be sudden, with only a cough for a warning. There is often agitation in the early stages. Other signs include labored, ineffective breathing, until the person is no longer breathing (apneic). Loss of consciousness occurs if the obstruction is not relieved. Treatment of airway obstruction due to a foreign body includes the Heimlich maneuver for adults, a series of five abdominal thrusts for children over 1 year of age, and a combination of five back blows with the flat of the hand and five abdominal thrusts with two fingers on the upper abdomen for infants.