远端预处理对体外循环下心脏瓣膜置换术患者脑损伤的保护作用

The protective effect of remote ischemic preconditioning on the brain injury of patients treated with cardiac valve replacement under cardiopulmonary bypass

目的：探讨远端预处理（remote ischemic preconditioning,RIPC）对体外循环（cardiopulmonary bypass,CPB）下瓣膜置换手术中脑损伤的保护作用。方法：将体外循环心脏瓣膜置换术患者40例随机分为远端预处理组（RIPC组）和对照组,各20例。麻醉诱导后CPB前,以骨科充气式压力止血带环扎左上臂上施压（压力200 mm Hg）,循环3次,每次5 min,间隔5 min;对照组处理同RIPC组,但止血带不充气。分别于麻醉诱导稳定5 min后（T0）和手术结束即刻（T1）、术后1 h（T2）、6 h（T3）和24 h（T4）5个时间点抽取颈内静脉球部血检测S-100β、神经元特异性烯醇化酶（NSE）。对于所有接受手术的患者分别在术前1 d和术后第3、8天行神经心理测验和评估。结果：2组患者S-100β和NSE蛋白水平在T1-T4均显著高于T0（P〈0.01）,但RIPC组S-100β在T1-T3和NSE水平在T1-T4时均明显低于对照组（P〈0.01）。RIPC组术后3 d简易智能量表和蒙特利尔认知评估量表评分均低于对照组（P〈0.05和P〈0.01）。结论：RIPC可降低CPB下心脏瓣膜置换术患者血清NSE、S-100β蛋白水平,降低患者术后认知功能障碍发生率,具有脑保护作用。

Objective： To investigate the protective effects of remote ischemic preconditioning（ RIPC） on the brain injury of patients treated with cardiac valve replacement under cardiopulmonary bypass（ CPB）. Methods： Forty patients treated with cardiac valve replacement under CPB were randomly divided into the RIPC group and control group（ CON group）（ 20 cases each group）. After induction of anesthesia and before cardiopulmonary bypass,the pressure of left upper arm in RIPC group was increased by cerclage with orthopedic inflatable pressure tourniquet,loop 3 times,5 min each time,and an interval of 5 min. The treatment of the CON group was the same as the RIPC group,but the tourniquet was not inflated. The levels of S-100β protein and NSE in internal carotid artery bulb were detected after 5 min of the induction of anaesthesia stability（ T0）,at the end of operation（ T1）,and at postoperative 1 h（ T2）,6 h（ T3） and 24 h（ T4）. The neuropsychology in all operation patients were tested and assessed before 1 day of operation and after 3 and 8days of operation. Results： The levels of S-100β and NSE in two groups at T2 to T4were significantly higher than those at T0（ P〈0. 01）,but the levels of S-100β at T2 and T3,and the levels of NSE at T2 to T4in RIPC group were significantly lower than those in CON group（ P〈0. 01）. The MMSE and Mo CA scores in RIPC group after 3 days of operation were lower than those in CON group（ P〈0. 05 to P〈0. 01）. Conclusions： The RIPC can decrease the levels of S-100β and NSE in the patients treated with cardiac valve replacement under CPB,and the incidence of cognitive impairment of patients,which can play a role on protecting brain.