【作者】 李彩凤；

【导师】 李利文；

【作者基本信息】 中南大学 ， 麻醉学， 2011， 硕士

【摘要】 目的：远隔缺血预处理和远隔缺血后处理能够减轻缺血-再灌注损伤,已经在大量的动物及少量的人体实验中得到证实。但是远隔缺血预处理和远隔缺血后处理在瓣膜置换手术中对缺血心肌是否有保护作用至今未见报道。本课题欲探讨左下肢的远隔缺血预处理能否对成人心脏瓣膜置换术中缺血心肌产生保护作用；本课题另一研究目的是观察左下肢的远隔缺血后处理在成人心脏瓣膜置换术中是否有心肌保护作用,并与远隔缺血预处理比较两者的的心肌保护作用是有差别。方法：将48名风湿性心脏瓣膜病变需行瓣膜置换术的病人随机分为三组：对照组(CON组,n=16),远隔缺血预处理组(RIPC组,n=16),远隔缺血后处理组(RPostC组,n=16)。远隔缺血预处理组于麻醉诱导后利用血压计袖囊充气至(?)200mmHg或放气,以足背动脉无法触及,同侧指端氧饱和度无法测出为标准,对病人左侧下肢实施5分钟缺血/5分钟再灌注处理,连续重复该过程3次；远隔缺血后处理组在主动脉阻断后和主动脉开放之前,利用血压计袖囊充气至(?)200 mmHg或放气,对病人左侧下肢实施5分钟缺血/5分钟再灌注处理,重复三个循环；对照组只是绑血压计袖囊,不充气。记录三组体外循环转流时间、主动脉阻断时间、术后恢复窦性心律比例、在ICU停留的时间及病人的住院时间等临床指标。分别于麻醉诱导前,停机时、停机后6小时和停机后24小时各时点抽取静脉血,测定心肌肌钙蛋白I(cTnI)、肿瘤坏死因子a (TNF-a)、细胞间粘附分子-1(ICAM-1)。结果：三组病例在年龄、体重、手术类型、体外循环转流时间、主动脉阻断时间以及术前cTnI、TNF-a和ICAM-1浓度无统计学差别(P>0.05),具有可比性。在停机时和停机后6小时,RIPC组和(?)RPostC组的血清cTnI浓度与对照组相比明显下降,三组间比较有统计学差异(停机时P<0.01,停机后6小时P<0.05)。在停机时和停机后6小时,RIPC组和RPostC组的血浆TNF-a和ICAM-1浓度较对照组明显所下降(P<0.01),有统计学意义。cTnI在RIPC组和RPostC组在停机时和停机后6小时均无统计学差别(停机时P=0.62,停机后6小时P=0.45)。在停机时和停机后6小时,血浆的TNF-a、ICAM-1在RIPC组和RPostC组均无统计学差别(P>0.05)。结论：(1)远隔缺血预处理在体外循环成人心脏瓣膜置换术中具有明显的心肌保护作用,进一步扩展RIPC在体外循环下心脏直视术的临床适应范围。(2)远隔缺血后处理可以减轻体外循环成人心脏瓣膜置换术中缺血心肌的再灌注损伤,证实RPostC在体外循环下心脏直视术的可行性和安全性。(3)在以肌钙蛋白Ⅰ作为评价心肌缺血再灌注损伤的指标,远隔缺血预处理和远隔缺血后处理在体外循环成人心脏瓣膜置换术中的心肌保护作用无明显差别。更多还原

【Abstract】 Objective:The remote ischemic preconditioning (RIPC) and Remote ischemic postconditioning (RPostC) had been also proved their effect in preventing the tissue from IR injury in a large amount of animal experiments and a few clinical trials. However, the clinical applicability of RIPC and RPostC in valve replacement remains to be determined. The present study is aimed to investigate whether left lower limb ischemic preconditioning is beneficial for patients undergoing valve replacement surgery. Another objective of the present study is to observe whether left lower limb ischemic postconditioning is beneficial for patients undergoing valve replacement surgery, and compare the protective of RIPC to RPostC on myocardium I/R injury.Methods:48 adult patients undergoing valve replacement surgery were randomly assigned to three groups:control group (n=16), RIPC group (n=16) and RPostC group (n=16).RIPC consisted of three 5-min cycles of left lower limb ischemia, induced by a manual cuff-inflator placed on the left thigh and inflated 200 mmHg before CPB, with an intervening 5-min reperfusion during which the cuff was deflated. RPostC induced by conditioning three cycles of 5-min of ischemia and reperfusion during the ischemic phase of myocardium.The bypass time, aortic cross-clamping time, the proportion of postoperative sinus rhythm intensive care unit(ICU) length of stay and other clinical data were recorded in three groups. The cTnI, TNF-a and ICAM-1 was measured before surgery and at 0,6 and 24 h after CPB.Results:Three groups of patients in age, weight, cardiopulmonary bypass time, aortic cross-clamp time and preoperative cTnI,TNF-a and ICAM-1 were not significantly different(P>0.05).The cTnI/TNF-a and ICAM-1 of three groups were increased significantly than the basis of value at the point of the end of CPB and 6 hours after CPB.AT the point of the end of CPB, the cTnl, TNF-a and ICAM-1 in RIPC and RPostC were significantly lower than that in control group(P<0.01).6 hours after CPB, the cTnI, TNF-a and ICAM-1 in RIPC and RPostC were lower than that in control group(P<0.05).The cTnI, TNF-a and ICAM-1 of RIPC and RPostC were not different at three time points (P>0.05).Conclusions:The present study demonstrates that adult patients undergoing valve replacement surgery could benefit from RIPC, using transient left lower limb ischemia. The present study also shows that RpostC can reduce the myocardial ischemia-reperfusion injury in adult patients undergoing valve replacement surgery;The RIPC and RPostC provide the same protective effect with respect to reduce postoperative cTnl release.更多还原