Drowning

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Drowning, death by suffocation due to the presence of water in the respiratory system.

Resuscitation by artificial respiration can prevent the death of a person with water in the lungs if instituted quickly. Because of the constant need of body tissues for oxygen, even a few minutes of suffocation can result in brain damage or death. The exception to this appears in persons who have been submerged in cold water. Some victims have been completely revived, without brain damage, after having been underwater for as long as a half hour. This phenomenon, the so-called diving reflex, has long been observed in sea mammals. Activated when the face is plunged into water below 21° C (70° F), it slows body processes so that oxygen-bearing blood is diverted to the heart and brain.

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