[Hypothermia. Physiopathology, clinical picture and treatment].

Hypothermia is defined as a lowering of core body temperature to 35 degrees C or below. Hypothermia may be advantageous in connexion with cardiac surgery or it may be fatal in connexion with accidental hypothermia. Accidental hypothermia is a problem which may be underestimated because of limited awareness. Severe hypothermia occurs when the body temperature falls below 28 degrees C. The patient may be unconscious, with such severely depressed vital signs that he appears to be dead. All such patients should undergo cardiopulmonary resuscitation in addition to rewarming, because reliable determination of death is nearly impossible without the restoration of adequate cardiovascular support, maintaining serum acid base balance, arterial oxygenation and intravascular volume levels within appropriate physiological ranges. Three controversial issues in connexion with treatment of the hypothermic patient are reviewed. These are correction of blood gas analyses, the phenomenon of afterdrop and cardiopulmonary resuscitation.