Normothermia: Ideal temperature for cardio pulmonary bypass

Abstract

Hypothermic systemic perfusion has remained as an integral part of Cardiopulmonary bypass (CPB). Myocardial and Cerebral protection has been claimed as advantage of hypothermia. Normothermic CPB has been proved to be a safe alternative with good myocardial and cerebral protection. From March 2000 to Oct 2003, 346 cases were done under CPB with normothermic Systemic and myocardial perfusion. The age range being 7 months to 80 years with a mean of 43.69±20.41 years. The M:F ratio is 236∶110. (2.14∶1). The procedures performed include congenital heart disease, valve procedures, coronary artery bypass grafting and others. The following peri- and postoperative data were analysed statistically to evaluate the efficacy of Normothermic CPB. Total CPB time was 101.24±50.45 minutes, time interval between onset of CPB and aortic cross clamp was 5.23±2.31 minutes and release of cross clamp and off CPB was 7.34±3.85 minutes. Arrhythmia occurred during weaning off CPB in 5 (1.44%) patients. Ionotropes used during weaning from CPB in 93 (26.87%) patients of which 76 (21.96%) cases required only dopamine. Vasodilators required during weaning off CPB in 15 (4.33%) patients. Development of systemic hyperthermia during rewarming was in 1 (0.28%) case & difference of central and peripheral blood pressure in 7 (2.03%) cases. Postoperative ventilation duration was 5.04±4.79 hours. Total bleeding was 237±115 mls, re-exploration was done in 6 (1.73%) cases. Postoperative neurological complication in 2 (0.57%), renal impairment requiring dialysis in 2 (0.57%) & GI bleed in 2 (0.57%) cases. Mortality was in 6 cases of which 1 (0.28%) was due to inability to wean off from CPB. We conclude normothermic systemic and myocardial perfusion during CPB is physiological, reduces morbidity and is a safe alternative to hypothermic CPB.