关于心脏手术中自体血回收有效性随机试验的荟萃分析

背景在心脏手术中可以通过自体血回收来避免输注同种异体血。另外已有人提出，血液中的碎片可能会增加卒中或神经意识功能障碍的风险，因此，清除回收血中的碎片可改善患者的预后。在此研究中，我们试图通过系统性回顾已发表的随机控制性试验进行荟萃分析，明确在心脏手术中自体血回收的整体安全性和有效性。方法全面检索找出关于所有有关心脏手术中应用自体血回收技术的所有随机试验。截止到2008年11月的MEDLINE、Cochrane图书馆、EMBASE和摘要资料库均被检索完全。将所有心脏手术中应用自体血回收技术与未应用自体血回收技术进行比较，并且报道至少一个明确的临床结果的随机试验均被列为研究对象。随机效应模型被用来依次计算比值比（OR，95％可信区间）、二分法加权平均差（WMD，95％可信区间）和连续变量。结果包括2282例患者在内的31个随机试验最终被作为研究对象进行荟萃分析。在心脏手术中，进行手术中自体血回收减少了接触同种异体异基因血制品（比值比0．63，95％可信区间：0．43—0．94，P=0．02）及红细胞（比值比0．60，95％可信区间：0．39—0．92，P=0．02）的概率，也降低了平均每例患者输注同种异体异基因血制品的总量（加权平均差-256ml，95％可信区间：-416--95ml，P=0．002）。但在以下几个方面进行自体血回收组与未进行自体血回收组之间并无差异，包括：院内死亡率（比值比0．65，95％可信区间：0．25—1．68，P=0．37）、手术后卒中或短暂缺血性发作（比值比0．59，95％可信区间：0．20～1．76，P=0．34）、房颤（比值比0．92，95％可信区间：0．69—1．23，P=0．56）、肾功能衰竭（比值比0．86，95％可信区间：0．41—1．80，P=0．70）、感染（比值比1．25，95％可信区间：0．75—2．10，P=0．39）、接受新鲜冰冻血浆治疗（比值比1．16，95％可信区间：0．82—1．66，P=0．40）以及接受血小板输注治疗（比值比0．90，95％可信区间：0．63—1．28，P=0．55）。结论现有的证据表明应用自体血回收技术可减少心脏手术中患者异体血制品或红细胞的输注。进一步的分析认为，只有在收集失血和（或）剩余机血，或在整个手术过程中应用自体血回收技术才是有利的。如果只在体外循环期间用自体血回收技术作为心内吸引，则对于血液保护没有明显效应且增加新鲜冰冻血浆的输注。

BACKGROUND： Cell salvage may be used during cardiac surgery to avoid allogeneic blood transfusion. It has also been daimed to improve patient outcomes by removing debris from shed blood, which may increase the risk of stroke or neurocognitive dysfunction. In this study, we sought to determine the overall safety and efficacy of cell salvage in cardiac surgery by performing a systematic review and meta-analysis of published randomized controlled trials. METHODS： A comprehensive search was undertaken to identify all randomized trials of cell saver use during cardiac surgery. MEDLINE, Cochrane Library, EMBASE, and abstract databases were searched up to November 2008. All randomized trials comparing cell saver use and no cell saver use in cardiac surgery and reporting at least one predefined clinical outcome were induded. The random effects model was used to calculate the odds ratios （ OR, 95% confidence intervals [ CI ] ） and the weighted mean differences （WMD, 95% CI） for dichotomous and continuous variables, respectively. RESULTS： Thirty-one randomized trials involving 2282 patients were included in the meta-analysis. During cardiac surgery, the use of an intraopera- five cell saver reduced the rate of exposure to any allogeneic blood product （ OR 0. 63, 95% CI ： 0.43 - 0.94, P = 0. 02 ） and red blood cells （ OR 0.60, 95% CI ： 0.39 - 0.92, P = 0. 02） and decreased the mean volume of total allogeneic blood products transfused per patient （ WMD - 256 ml, 95 % CI ： - 416 to - 95 ml, P=0. 002 ）. There was no difference in hospital mortality （OR 0.65, 95% CI ： 0.25 - 1.68, P = 0. 37）, postoperative stroke or transient ischemia attack （ OR 0.59, 95% CI： 0.20-1.76, P=0.34）, atrial fibrillation （OR0.92, 95% CI： 0.69-1.23, P=0.56）, renal dys- function （OR0.86, 95% CI： 0.41 -1.80, P=0.70）, infection （OR1.25, 95% CI： 0.75 -2.10, P=0.39）, patients requiring fresh frozen plasma （OR 1.16, 95% CI ： 0.82 - 1.66, P = 0.40）, and patients requiring platelet transfusions （OR0. 90, 95% CI. 0. 63 - 1.28, P = 0. 55） between cell saver and nonceU saver groups. CONCLUSIONS： Current evidence suggests that the use of a cell saver reduces exposure to allogeneic blood products or red blood cell transfusion for patients undergoing cardiac surgery. Subanalyses suggest that a cell saver may be beneficial only when it is used for shed blood and/or residual blood or during the entire operative period. Processing cardiotomy suction blood with a cell saver only during cardiopulmonary bypass has no significant effect on blood conservation and increases fresh frozen plasma transfusion.