Impact of Postoperative Hypothermia on Bleeding in Coronary Artery Bypass Surgery

Abstract

H ypothermia is defined as a core body temperature less than 35. Although hypothermia is known to decrease the metabolic demand of the body and promotes impairment in various systems causing decrease oxygen release to tissues. Hypothermia results in impairment of the coagulation cascade and the white cell count also decreases , hypothermia impairs immune function so nosocomial pneumonia will occur in over half of patients who are hypothermic for more than 7 days. Hypothermia-induced increase in catecholamines leads to an increase in cardiac output and oxygen demand As a result of prolonged hypothermia, bleeding time will be increased due to its effects on platelets count and function. Platelets also are been sequestrated through RES system (liver/spleen). Postoperative bleeding and transfusion occur few hours after surgery 6-24 hrs, so we monitor carefully the body core temperature (BMT) in ICU for the first 6 hours postoperatively. The aim of this prospective study was to evaluate the influence of core temperature on postoperative amount of blood loss, transfusion requirements, coagulation profile and the length of hospital stay in patients undergoing on pump coronary artery bypass grafting operations