Myocardial Protection Of Penehyclidine Pretreatment On Patients Undergoing Cardiac Valve Replacement During Peri-cardiopulmonary Bypass

Objective:To study myocardial protection of penehyclidine on patients undergoing cardiac valve replacement during peri-cardiopulmonary.Methods:45 patients undergoing cardiac valve replacement under cardiopulmonary bypass (CPB) were randomized into 3 groups (n=15):control group (group C), low dose PHC group (group PL) and high dose PHC group (group PH). All the patients were anesthetized with intravenous injection of midazolam (0.1～0.12mg·kg-1), etomidate (0.2～0.3mg·kg-1), fentanyl (10～15μg·kg-1), pipecuronium bromide (0.1～0.15mg·kg-1), and were endotrachaelly intubated. Control ventilation was conducted and PFTCO2 was maintained between 35 to 40 mmHg. Anesthesia was maintained with addition of midazolam, fentanyl and pipecuronium bromide. Saline (group C) or 0.02g·kg-1 of PHC (groups PL and PH) was given intravenously before skin incision, and an additional dose (0.02g·kg-1) of PHC was delivered before sternotomy only in group PH. Concentration of cardiac troponin I (cTnI), activity of creatine phosphokinase (CK) and creatine phosphokinase isoenzyme (CK-MB) were measured before anesthesia (T0), before aortic cross-clamp (T1), at the beginning of aortic opening (T2),30min after aortic opening (T3),2h (T4), 6h (T5),12h (T6) and 24h (T7) after CPB termination.Results:There were no statistical differences in CPB time, aortic cross-clamp time and surgical procedure time among the three groups (P> 0.05). cTnI concentration, CK and CK-MB activity increased at the time points of T1-T7 (P＜0.01) in all the three groups, with the lower increasing extent in both groups PL and PH, but without difference between group PL and group PH. There were 8,10 and 11 cases with heart automatical rebeating, in group C, group PL and group PH, with a higher rate of heart automatical rebeating in groups PL and PH than in group C. The volume of blood drainage from the wound during post-operative 24h in C group was more than that in groups PL and PH.Conclusions:Administration of PHC (0.02g·kg-1) before surgery is able to protect myocardial function from ischemia-reperfusion injury and from CPB, and another same dose of PHC dose not further enhance its myocardial protective effect.