Is there a relationship between systemic perfusion temperature during coronary artery bypass grafting and extent of intraoperative ischemic central nervous system injury?

Abstract

This study was designed to compare the volume of cerebral infarction in patients operated on under either hypothermic or tepid/normothermic perfusion for coronary revascularization. A randomized trial with preoperative, postoperative, and late neurologic evaluation was conducted in patients undergoing coronary revascularization having either hypothermic or tepid/normothermic perfusion for coronary revascularization. The goal was to determine whether perfusion temperature correlated with neurologic dysfunction associated with coronary artery bypass. Twelve intraoperative ischemic strokes occurred during coronary revascularization in a series of 291 patients. Six of these were in the group receiving hypothermic perfusion and 6 in groups receiving the tepid/normothermic perfusion. Measuring the infarct volume documented that 3 of the strokes in each group resulted in minor or small infarcts and 3 in each group were significant, major strokes. The volume of infarction, whether including all 6 patients in each group or only those with major strokes, was no different between the hypothermic and the tepid/normothermic groups. In this series of 291 patients randomized to perfusion temperature, we observed no relationship between the size of a cerebral ischemic infarct and the perfusate temperature during coronary revascularization.