七氟醚后处理对体外循环下冠状动脉旁路移植术病人心肌缺血再灌注损伤的影响

Effects of sevoflurane postconditioning on myocardial ischemia-reperfusion injury in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass

目的 探讨七氟醚后处理对体外循环（CPB）下冠状动脉旁路移植术病人心肌缺血再灌注损伤的影响。方法择期行冠状动脉旁路移植术病人40例，性别不限，年龄55～64岁，BMI〈30kg／m^2，NYHA心功能分级Ⅰ～Ⅲ级，随机分为2组（n=20）：对照组（c组）和七氟醚后处理组（s组）。S组于主动脉开放即刻通过体外循环机吸入2％七氟醚，持续15min，C组不给予任何处理。分别于麻醉诱导后、CPB转流前、停机后10min、术毕、术后6和24h时，记录MAP、HR、CVP、平均肺动脉压、肺动脉楔压、CO和SvO2，计算CI、SVI、体循环血管阻力指数和肺循环血管阻力指数。分别于主动脉阻断前、复灌6h和术后24h时，中心静脉取血样，测定血浆肌酸激酶（CK）、肌酸激酶同工酶（CK—MB）和乳酸脱氢酶（LDH）的活性以及肌钙蛋白I（TnI）浓度。分别于主动脉阻断前和CPB停机时，取右心耳心肌组织，观察心肌细胞超微结构，并对心肌细胞损伤程度进行评分。结果两组间各时点血液动力学和心功能指标比较差异无统计学意义（P〉0．05）。与c组比较，s组复灌6h时血浆CK—MB和LDH活性降低，术后24h时血浆CK活性和TnI浓度降低，CPB停机后心肌细胞损伤程度评分降低（P〈0．05）。结论七氟醚后处理可减轻CPB下冠状动脉旁路移植术病人心肌缺血再灌注损伤。

Objective To investigate the effects of sevoflurane postconditioning on myocardial ischemiareperfusion （I/R） injury in patients undergoing coronary artery bypass grafting （CABG） with cardiopulmonary bypass （CPB）. Methods Forty NYHA Ⅰ -Ⅲ patients of both sexes, aged 55-64 yr, with BMI 〈 30 kg/m2, scheduled for CABG under CPB, were randomly divided into 2 groups （n = 20）： control group （group C） and sevoflurane postconditioning group （group S）. Anesthesia was induced with midazolam and/or etomidate, fentanyl and rocuronium. Patients were tracheal intubated and mechanically ventilated. Anesthesia was maintained with iv infusion of propofol and intermittent iv injection of fentanyl and pipecuronium. In group S, 2% sevoflurane was inhaled continuously for 15 min immediately after aortic unclamping. After anesthesia induction, before CPB, 10 min after the end of CPB, at the end of operation, and 6 and 24 h after operation, MAP, HR, CVP, mean pulmonary arterial pressure, pulmonary arterial wedge pressure, CO and SvO2 were recorded, and CI, SVI, systemic vascular resistance index and pulmonary vascular resistance index were calculated. Blood samples were taken from central vein before aortic clamping, at 6 h of reperfusion and 24 h after operation for determination of plasma creatine ki- nase （CK）, creatine kinase isoenzyme （CK-MB） and lactate dehydrogenase （LDH） activities and troponin I （TnI） concentrations. Myocardial tissues were obtained from right auricle before aortic clamping and at the end of CPB for observation of the ultrastructure and the severity of myocardial injury was assessed. Results There was no significant difference in hemodynamics and parameters of cardiac function between the two groups （P 〉 0.05）. Compared with group C, plasma CK-MB and LDH activities at 6 h of reperfusion and plasma CK activity and TnI concentrations at 24 h after operation were significantly decreased and the myocardial injury was significantly reduced after the end of CPB in group S （ P 〈 0.05）. Conclusion Sevoflurane postconditioning can protect myocardium against I/R injury induced by CPB in patients undergoing CABG.