Background: Venous thromboembolic (VTE) disease has a high incidence following trauma, but debate remains regarding optimal prophylaxis. Thrombelastography (TEG) has been suggested to be optimal in guiding prophylaxis. Thus, we designed a phase II randomized controlled trial to test the hypothesis that TEG-guided prophylaxis with escalating low-molecular weight heparin (LMWH), followed by antiplatelet therapy would reduce VTE incidence.
背景：静脉血栓栓塞（VTE）疾病在创伤后有很高的发病率，但关于最佳预防仍存在争议。血栓弹力图（TEG）被认为是指导预防的最佳方法。因此，我们设计了一项II期随机对照试验，以检验以下假设：在TEG指导下，使用逐步升高的低分子量肝素（LMWH）进行预防，然后进行抗血小板治疗，可以降低VTE的发生率。

Methods: Surgical intensive care unit trauma patients (n = 50) were randomized to receive 5,000 IU of LMWH daily (control) or to TEG-guided prophylaxis, up to 5,000 IU twice daily with the addition of aspirin, and were followed up for 5 days. In vitro studies were also conducted in which apheresis platelets were added to blood from healthy volunteers (n = 10).
方法：外科重症监护室创伤患者（n = 50）随机接受每日5，000 IU LMWH（对照）或TEG指导的预防性治疗，每日两次，最多5，000 IU，并添加阿司匹林，并随访5天。还进行了体外研究，其中将单采血小板添加到来自健康志愿者（n = 10）的血液中。

Results: Control (n = 25) and TEG-guided prophylaxis (n = 25) groups were similar in age, body mass index, Injury Severity Score, and male sex. Fibrinogen levels and platelet counts did not differ, and increased LMWH did not affect clot strength between the control and study groups. The correlation of clot strength (G value) with fibrinogen was stronger on Days 1 and 2 but was superseded by platelet count on Days 3, 4, and 5. There was also a trend in increased platelet contribution to clot strength in patients receiving increased LMWH. In vitro studies demonstrated apheresis platelets significantly increased clot strength (7.19 ± 0.35 to 10.34 ± 0.29), as well as thrombus generation (713.86 ± 12.19 to 814.42 ± 7.97) and fibrin production (274.03 ± 15.82 to 427.95 ± 16.58).
结果：对照组（n = 25）和TEG指导的预防组（n = 25）在年龄、体重指数、损伤严重程度评分和男性性别方面相似。纤维蛋白原水平和血小板计数没有差异，增加LMWH不影响对照组和研究组之间的凝块强度。在第1天和第2天，血凝块强度（G值）与纤维蛋白原的相关性更强，但在第3、4和5天被血小板计数取代。在接受增加LMWH的患者中，血小板对凝块强度的贡献也有增加的趋势。体外研究表明，单采血小板显著增加了凝块强度（7.19 ± 0.35至10.34 ± 0.29），以及血栓生成（713.86 ± 12.19至814.42 ± 7.97）和纤维蛋白生成（274.03 ± 15.82至427.95 ± 16.58）。

Conclusion: Increased LMWH seemed to increase platelet contribution to clot strength early in the study but failed to affect the overall rise clot strength. Over time, platelet count had the strongest correlation with clot strength, and in vitro studies demonstrated that increased platelet counts increase fibrin production and thrombus generation. In sum, these data suggest an important role for antiplatelet therapy in VTE prophylaxis following trauma, particularly after 48 hours.
结论：在研究早期，增加LMWH似乎增加了血小板对凝块强度的贡献，但未能影响整体凝块强度的升高。随着时间的推移，血小板计数与凝块强度的相关性最强，体外研究表明，血小板计数增加会增加纤维蛋白的产生和血栓的生成。总之，这些数据表明抗血小板治疗在创伤后预防VTE中具有重要作用，特别是在创伤后48小时。

Level of evidence: Therapeutic study, level III.
证据等级：治疗性研究，III级。