目的 比较利伐沙班片和低分子肝素钙注射液预防老年关节置换术后下肢深静脉血栓的临床疗效。方法 选取2015年2月—2016年5月天津港口医院收治的关节置换术患者120例为研究对象，所有患者根据用药方案不同分为低分子肝素组（64例）和利伐沙班组（56例）。低分子肝素组术后皮下注射低分子肝素钙注射液，0.2 mL/次，1次/d，第3天后剂量调整为0.4 mL/d。利伐沙班组术后口服利伐沙班片，10 mg/次，1次/d。两组患者连续治疗10 d。比较观察两组的深静脉血栓发生率、术中失血量、血液相关指标和血栓弹力图（TEG）。结果 治疗后，两组深静脉血栓发生率比较差异无统计学意义。在关节置换手术中，两组术中总失血量和显性失血量比较差异无统计学意义。术后2、4 d，两组血红蛋白、血小板计数、PT和APTT比较差异无统计学意义。术后2、4 d，利伐沙班组D-二聚体（D-D）和纤维蛋白降解产物（FDP）显著低于低分子肝素组，国际标准化比值（INR）显著高于低分子肝素组，两组比较差异具有统计学意义（P<0.05）。术后2 d，利伐沙班组凝血因子反应时间（R）、血凝块成形时间（K）显著高于低分子肝素组，描记图最大曲线弧度作切线与水平线的夹角（Angle）、最大振幅（MA）和综合凝血指数（CI）显著低于低分子肝素组，两组比较差异具有统计学意义（P<0.05）。在治疗期间，低分子肝素组和利伐沙班组不良反应总发生率分别为46.88%、37.50%，两组比较差异具有统计学意义（P<0.05）。结论 利伐沙班片预防老年关节置换术后下肢深静脉血栓优于低分子肝素钙注射液，可降低血液高凝状态，安全性较好，具有一定的临床推广应用价值。

Objective To compare the clinical effect of Rivaroxaban Tablets and Low-Molecular-Weight Heparins Calcium Injection in prevention of deep venous thrombosis of lower extremity after joint replacement of elderly patients. Methods Patients (120 cases) with joint replacement in Tianjin Port Hospital from February 2015 to May 2016 were enrolled in this study. According to the difference treatment plan, patients were divided into the low molecular weight heparin group (64 cases) and the rivaroxaban group (56 cases). Patients in the low molecular weight heparin group were sc administered with Low-Molecular-Weight Heparins Calcium Injection after the operation, 0.2 mL/time, once daily, and since 3th day, the dose was adjusted to 0.4 mL/d. Patients in the rivaroxaban group were po administered with Rivaroxaban Tablets, 10 mg/time, once daily. Patients in two groups were treated for 10 d. After treatment, the incidences of deep venous thrombosis were evaluated, and intraoperative blood loss, blood related indexes, and TEG in two groups were compared. Results After treatment, there was no significant difference in the incidence of deep venous thrombosis between two groups. In the arthroplasty, there was no significant difference in the total blood loss and the dominant blood loss in two groups. At 2 and 4 d after operation, there was no significant difference on hemoglobin, platelet count, PT and APTT between two groups. At 2 and 4 d after operation, the D-D and FDP in the rivaroxaban group were significantly lower than those in the low molecular weight heparin group, but the INR in the rivaroxaban group was significantly higher than that in the low molecular weight heparin group, and there was difference between two groups (P < 0.05). At 2 d after operation, the R and K in the rivaroxaban group were significantly higher than those in the low molecular weight heparin group, but the Angle, MA, and CI in the rivaroxaban group were significantly lower than that in the low molecular weight heparin group, and there was difference between two groups (P < 0.05). During the period of treatment, the incidence of adverse reactions in the low molecular weight heparin group and rivaroxaban group were 46.88% and 37.50%, respectively, and there was difference between two groups (P < 0.05). Conclusion Rivaroxaban Tablets were better than Low-Molecular-Weight Heparins Calcium Injection in prevention of deep venous thrombosis of lower extremity after joint replacement of elderly patients, can decrease hypercoagulable state of blood, with good safety, which has a certain clinical application value.