Myocardial protective effect of nicorandil premedication In patients undergoing coronary artery bypass grafting with cardiopulmonary bypass

Abstract

Objective To investigate the cerebral protective effect of nicorandil premedication in patients undergoing coronary artery bypass grafting (CABG) under cardiopulmonary bypass (CPB) by the mini-mental state examination (MMSE) and blood neural specific enolase ( NSE) and S100β protein (S100β) concentration monitoring.Methods Thirty ASA II or III patients (28 male, 2 female) aged 50-80 yr weighing 45-90 kg undergoing CABG under CPB were randomized to receive nicorandil 10 mg orally 30 min before induction of anesthesia (group N, n = 15) or no nicorandil (group C, n = 15). Every patient underwent MMSE 24 h before and after CABG. Blood samples were taken before induction of anesthesia (T1 ), 30 min after termination of CPB (T2), 6 h (T3) and 24h (T4) after operation for determination of blood NSE and S100β concentration. Results The two groups were comparable with respect to demographic data, duration of CPB and operation ( P 0.05 ) . The patients in both groups all recovered from CABG and discharged from hospital without serious complication such as brain infarct. The MMSE scores after operation were significandy lower than that before operation in both groups ( P 0.05), but the difference in the scores before and after operation was significantly smaller in group N than in group C (P 0.05). Blood NSE concentrations at T2 and T3 were significantly higher than the baseline ( at T1 ) in both groups ( P 0.05), but the increase was significantly smaller in group N than in group C ( P 0.05). The blood S100β concentration was significantly increased at T2 , T3 and T4 in group C but only at T4 in group N as compared to the baseline at T1 ( P 0.05). Conclusion Nicorandil given orally as premedication attenuates the decrease in postoperative MMSE score and the increase in blood NSE and S100β concentrations after CPB indicating its cerebral protective effect.