Neuronal and astroglial injuries in patients undergoing coronary artery bypass grafting and aortic arch replacement during hypothermic cardiopulmonary bypass

More than 50% of patients suffer neuropsychologic impairment after cardiac surgery. We measured neuron-specific enolase (NSE) and S-100 protein (S-100 ) in patients' serum as putative markers of neuronal and astroglial cell in jury, respectively. Group I (n = 13) underwent coronary artery bypass graft ing (CABG) with mild hypothermic capdiopulmonary bypass (CPB); Group II (n = 6) underwent aortic arch replacement with deep hypothermic CFB; Group III (n = 8) underwent CABG under normothermia without CPB. During and after th e operation, serum levels of NSE and S-100 were significantly increased onl y in Groups I and II (during CPB), NSE still being increased 12 h after sur gery in Group II. This suggests that neuronal and astroglial cell injuries are more likely in patients undergoing CABG with mild hypothermic CPB or ao rtic arch replacement with deep hypothermic CPB than in those undergoing CA BG under normothermia without CPB. However, these increases of NSE and S-10 0 failed to reflect clinical brain damage. Rather, an electroencephalogram, was only capable of detecting neurologic complications after surgery.