[Effect of tepid cardiopulmonary bypass in coronary artery bypass operation].

The effect of systemic temperature during cardiopulmonary bypass (CPB) surgery was evaluated in 100 patients. The patients were divided into three groups, based on systemic temperature during CPB; 28 degrees C, 30 degrees C, or 32 degrees C (tepid). Multidose cold crystalloid cardioplegia was administered for myocardial protection. Pump flow was maintained at 75 ml/kg/min. Methoxamine hydrochloride and phenothiazine were used to maintain systemic perfusion pressures between 60 and 80 mmHg. Preoperatively, there were no differences between groups in left ventricular ejection fraction or extent of coronary artery disease. The time required for CPB and weaning from CPB were significantly shorter in the 32 degrees C group than in either the 28 degrees C or the 30 degrees C group. There were significant differences in the doses of methoxamine hydrochloride and phenothiazine required in each group. Postoperatively, there were no significant differences in the incidence of myocardial infarction, stroke, or 30-day mortality between groups. In conclusion, tepid systemic perfusion shortens the length of CPB and does not differ significantly from cold perfusion with respect to mortality and morbidity.