Effect of remote ischemic preconditioning on hemostasis and fibrinolysis in head and neck cancer surgery: A randomized controlled trial

IntroductionThe aim of this randomized controlled trial was to investigate if remote ischemic preconditioning (RIPC) reduced platelet aggregation and increased fibrinolysis in cancer patients undergoing surgery and thereby reduced the risk of thrombosis.Materials and methodsHead and neck cancer patients undergoing tumor resection and microsurgical reconstruction were randomized 1:1 to RIPC or sham intervention. RIPC was administered intraoperatively with an inflatable tourniquet by four cycles of 5-min upper extremity occlusion and 5-min reperfusion. The primary endpoint was collagen-induced platelet aggregation measured with Multiplate as area-under-the-curve on the first postoperative day. Secondary endpoints were markers of primary hemostasis, secondary hemostasis, and fibrinolysis. Clinical data on thromboembolic and bleeding complications were prospectively collected at 30-day follow-up. An intention-to-treat analysis was performed.ResultsSixty patients were randomized to RIPC (n = 30) or sham intervention (n = 30). No patients were lost to follow-up. The relative mean [95% confidence interval] collagen-induced platelet aggregation was 1.26 [1.11;1.40] in the RIPC group and 1.17 [1.07;1.27] in the sham group on the first postoperative day reported as ratios compared with baseline (P = 0.30). Median (interquartile range) 50% fibrin clot lysis time was 517 (417–660) sec in the RIPC group and 614 (468–779) sec in the sham group (P = 0.25). The postoperative pulmonary embolism rate did not differ between groups (P = 1.0).ConclusionsRIPC did not influence hemostasis and fibrinolysis in head and neck cancer patients undergoing surgery. RIPC did not reduce the rate of thromboembolic complications.引言 本随机对照试验旨在探讨远程缺血预处理（remote ischemic preconditioning, RIPC）是否可降低手术中癌症患者的血小板聚集水平、提升纤维蛋白溶解活性，从而降低血栓形成风险。 材料与方法 将接受肿瘤切除及显微外科修复术的头颈部癌症患者按1:1比例随机分配至RIPC组与假干预组。RIPC于术中通过充气止血带实施，共4个循环，每个循环为上肢阻断5分钟、再灌注5分钟。主要终点为术后首日采用Multiplate检测仪检测的胶原诱导血小板聚集曲线下面积。次要终点包括一期止血、二期止血及纤维蛋白溶解相关标志物。研究于30天随访期前瞻性收集血栓栓塞与出血并发症的临床数据，并采用意向性治疗分析。 结果 共60例患者被随机分配至RIPC组（n=30）与假干预组（n=30），无患者失访。术后首日，以与基线的比值形式报告的胶原诱导血小板聚集相对均值[95%置信区间]在RIPC组为1.26[1.11;1.40]，在假干预组为1.17[1.07;1.27]（P=0.30）。RIPC组的50%纤维蛋白凝块溶解时间中位数（四分位间距）为517（417~660）秒，假干预组为614（468~779）秒（P=0.25）。两组术后肺栓塞发生率无显著差异（P=1.0）。 结论 RIPC未对接受手术的头颈部癌症患者的止血功能与纤维蛋白溶解活性产生影响，亦未降低血栓栓塞并发症的发生率。