Drowning

The Drowning - Death caused by suffocation and hypoxia (a lack of oxygen) associated with immersion in a fluid. Most often, the person inhales liquid into the lungs; but sometimes no liquid enters the lungs, a condition called dry drowning (see drowning, dry). People who are resuscitated after prolonged immersion are said to be victims of “near drowning”.

MECHANISM OF DROWNING
Initially, automatic contraction of a muscle at the entrance to the windpipe, a mechanism known as the laryngeal reflex, prevents water from entering the lungs; instead, the water enters the oesophagus and stomach. However, the laryngeal reflex impairs breathing and can quickly lead to hypoxia and to loss of consciousness. If the person is buoyant at this point and floats face-up, his or her chances of survival are reasonable because the laryngeal reflex begins to relax and normal breathing may then resume.

FIRST AID AND TREATMENT
An ambulance should be called and the person’s condition assessed. If he or she is not breathing and/or the pulse is absent, resuscitative measures should be started (see artificial respiration; cardiopulmonary resuscitation) and continued until medical help arrives.

Victims can sometimes be resuscitated despite a long period immersed in very cold water (which reduces the body’s oxygen needs). In all cases of successful resuscitation, the person should be sent to hospital, because life-threatening symptoms may develop some hours after rescue if water has passed from the lungs into the blood.