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

Objective: 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. Methods: 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. Results: 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. Conclusions: 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. (J Thorac Cardiovasc Surg 2000;119:230-2)