[Clinical benefits of normothermic cardiopulmonary bypass on postoperative systemic metabolism]

To evaluate the influence of body temperature during cardiopulmonary bypass (CPB) on postoperative systemic metabolism, 32 patients undergoing elective cardiac surgery were randomly assigned to either hypothermia (n = 16) or normothermia (n = 16). Serial hemodynamic parameters and blood samples were obtained after surgery. CPB and operation times were significantly shorter and the platelet reduction ratio during CPB [ = (platelets before CPB-platelets after CPB)/platelets before CPB] was significantly lower in normothermic patients than in hypothermic patients. The platelet reduction ratio was dependent on the minimum rectal temperature during CPB, the operation time, and the CPB time. In the early postoperative period, hypothermic patients had abnormally high systemic vascular resistance and a reduced cardiac index compared with the normothermic patients. There were no differences between 2 groups in postoperative hepatic and renal functions, changes in oxygen consumption, arterial-venous PCO2 or arterial-venous pH gradient. This study suggested a beneficial influence of normothermic CPB on postoperative hemodynamics. Normothermic CPB was not associated with adverse effects on postoperative metabolic recovery.