远程缺血预处理对心肺转流心脏瓣膜置换术患者心肌损伤的保护作用

目的探讨远程缺血预处理(RIPC)对心肺转流(CPB)下心脏瓣膜置换术患者心肌损伤的影响。方法 CPB心脏瓣膜置换术患者40例,随机均分为研究组(E组)和对照组(C组)。E组于麻醉诱导插管完毕稳定5min后,应用骨科气压止血带给左上肢加压至35kPa,5min后,减压至0kPa,5min后重复加压,共4次,而C组只固定止血带,不加压。分别于麻醉诱导插管完毕稳定5min后(T1)、主动脉开放30min后(T2)、CPB停止后2h(T3)、术后12h(T4)、术后24h(T5)测颈内静脉血心肌肌钙蛋白I(cTnI)及肌酸激酶同工酶(CK-MB)浓度。结果与T1相比,两组cTnI浓度在T2时升高达峰值,随后持续下降;两组CK-MB浓度在T2时开始升高,T3时升高达峰值,随后持续下降。E组cTnI、CK-MB浓度在T2～T5时均明显低于C组(P<0.05或P<0.01)。结论 RIPC可降低CPB下心脏瓣膜置换术患者围术期cTnI、CK-MB的释放,减少围术期血管活性药物用量,减轻心肌的缺血-再灌注损伤,具有一定的心肌保护作用。

Protective effects of remote ischemic preconditioning on myocardial injury in patients undergoing cardiac valve replacement with cardiopulmonary bypass

Objective To investigate the effects of remote ischemic preconditioning(RIPC) on myocardial injury in patients during cardiac valve replacement with cardiopulmonary bypass(CPB).Methods Forty patients undergoing cardiac valve replacement with CPB were randomly divided into two groups:control group(group C)and experiment group(group E).Five minutes after anesthesia induction,RIPC was induced by four 5-minute cycles of ischemia and reperfusion by inflating the left upper limb at 35 kPa with a tourniquet in group E,whereas the tourniquet was only fixed in place and not inflated in group C.The concentrations of serum cTnI and CK-MB from internal jugular vein,were determined at 5 min after induction(T1),30 min after aortic off-clamping(T2),2 h after cessation of CPB(T3),12 h(T4) and 24 h(T5) after operation.Results Compared with T1,the concentration of cTnI in both groups was increased and peaked at T2,and began to drop down afterwards;the concentration of CK-MB in both groups was increased T2 and peaked at T3,and began to drop down afterwards.The levels of cTnI and CK-MB in group E were significantly lower than those in group C from T2 to T5(P<0.05 or P<0.01).Conclusion RIPC can decrease the perioperative release of cTnI and CK-MB in patients undergoing cardiac valve replacement with CPB,reduce the perioperative consumption of vasoactive drugs,alleviate myocardial ischemia-reperfusion injury,and thus has a protective effect on the myocardial injury during CPB.