Hypothermia

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Hypothermia, condition in which body temperature falls drastically as a result of exposure to cold. It may occur, for example, in hikers caught in a sudden cold front without sufficient clothing. The elderly can die from hypothermia at temperatures that would not harm younger persons. The condition involves a paradoxical response to sudden cold: the shutting off of blood flow to the body's surface. First aid may involve wrapping the victim in blankets (along with the rescuer, if necessary). Despite customary belief, alcohol causes loss of heat and should not be given. Treatment at a hospital involves slowly raising the body temperature by various means.

Hypothermia may also be induced for medical purposes. Reduction in body temperature causes a slowing of the metabolism. This is useful in certain types of surgery and to reduce bleeding in a particular part of the body.

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