Hypothermia in Hemorrhagic Shock

Abstract

Precooling to 28°C alters the course of hemorrhagic shock in the dog by prolonging the period of tolerance to severe hypotension, and by prolonging the survival time after transfusion from an average of several hours to an average of 30 hours. Precooling does not prevent death. But if an antibiotic is given at the time of transfusion all precooled dogs recover, whereas normothermic dogs given an antibiotic at the time of transfusion do not recover. Precooling protects the dog in hemorrhagic shock by sustaining the antibacterial defense mechanisms, which disintegrate rapidly in the normothermic dog. The protective effects of cooling is not secured if it is applied after the induction of hemorrhagic shock. The effects of hypothermia upon the cardiovascular dynamics are described and their significance discussed.