血栓弹力图评价关节置换后低分子肝素和利伐沙班的抗凝效果

Anticoagulant effect of low-molecular-weight heparin versus rivaroxaban after arthroplasty assessed by thromboelastography

背景:低分子肝素和利伐沙班是髋膝关节置换后常用的2种抗凝药物。低分子肝素可能导致血小板减少,利伐沙班并未证明对血小板有影响。研究表明,两者均可降低深静脉血栓的发生率,然而目前临床上对于两者的选择仍然存在争议。目的:利用血栓弹力图评价行髋膝关节置换患者使用低分子肝素或利伐沙班抗凝后的凝血功能改变,并分析2种药物的抗凝效果及血小板计数差异。方法:对2014至2017年在重庆医科大学附属第一医院骨科行初次髋膝关节置换的397例患者进行前瞻性研究。患者随机分为2组,低分子肝素组195例患者术后12 h皮下注射低分子肝素4 000 IU抗凝治疗;利伐沙班组202例患者术后12 h开始使用10 mg利伐沙班抗凝治疗。所有患者分别于术前、术后第1,3,5,7天行血栓弹力图及血小板计数检查。比较不同时间的高凝患者比例及血小板计数差异,并分析原因。结果与结论:(1)低分子肝素组术后第1-7天高凝状态患者比例逐渐增加,术后第7天达93.1%;利伐沙班组术后第3天高凝状态患者比例较第1天降低,第3-7天高凝状态患者比例逐渐增加,术后第7天达75.3%;2组比较差异有显著性意义(P <0.05);(2)2组患者术后第3天患者血小板计数平均值均较术前轻微降低;而第3-7天血小板计数平均值逐渐增加,至第7天明显高于术前水平,且利伐沙班组血小板计数平均值高于低分子肝素组,差异有显著性意义(P <0.05);(3)血栓弹力图检测结果提示,髋膝关节置换后使用利伐沙班的抗凝效果优于低分子肝素;低分子肝素可能抑制术后血小板数量的反应性增加。

BACKGROUND:Low-molecular-weight heparin and rivaroxaban are commonly used anticoagulant drugs after hip and knee arthroplasties.Low-molecular-weight heparin may cause decrease in platelets,and rivaroxaban has been shown to make no effect on platelets.Both of them have been shown to decrease the incidence of deep venous thrombosis,while these choices in clinic still remain controversial.OBJECTIVE:To evaluate the coagulation function of patients undergoing hip or knee arthroplasty after anticoagulation using low-molecular-weight heparin or rivaroxaban by thromboelastograph,and to analyze the differences in anticoagulant effect and platelet count between two drugs.METHODS:A prospective study was conducted,including 397 patients undergoing unilateral knee or hip arthroplasty at the Department of Orthopedics,the First Affiliated Hospital of Chongqing Medical University from 2014 to 2017.The patients were randomly divided into two groups,195 patients in the low-molecular-weight heparin group received subcutaneous injection of low molecular weight heparin(4 000 IU)at 12 hours postoperatively.202 patients in the rivaroxaban group received 10 mg of rivaroxaban orally at 12 hours postoperatively.Thromboelastograph and platelet count were performed at baseline,1,3,5 and 7 days postoperatively.The differences of proportion of hypercoagulability and platelet count were compared between two groups at different time points,and the reason was analyzed.RESULTS AND CONCLUSION:(1)In the low-molecular-weight heparin group,the proportion of patients with hypercoagulability increased gradually from 1 to 7 days after surgery,which reached to 93.1%on day 7.In the rivaroxaban group,the proportion of patients with hypercoagulability on day 3 was lower than that on day 1 after surgery,and the proportion of hypercoagulability increased gradually during the 3-7 days,which reached to 75.3%on day 7.There was significant difference in the proportion of hypercoagulability between two groups(P<0.05).(2)The average platelet count in both groups decreased slightly than that at baseline.However,the average platelet count increased during 3-7 days after surgery,and the count on day 7 was significantly higher than the baseline level.The average platelet count in the rivaroxaban group was significantly higher than that in the low-molecular-weight heparin group(P<0.05).(3)Thromboelastograph results indicate that the anticoagulant effect of rivaroxaban is better than that of low-molecular-weight heparin after hip and knee arthroplasties,and the latter may inhibit the reactivity of platelet counts after surgery.