Bump Gregory M, Dandu Madhavi, Kaufman Samuel R, Shojania Kaveh G, Flanders Scott A
Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15213-2582, USA.
J Hosp Med. 2009 May;4(5):289-97. doi: 10.1002/jhm.450.
Guidelines recommend pharmacologic prophylaxis for hospitalized medical patients at increased risk of thromboembolism. Despite recommendations, multiple studies demonstrate underutilization. Factors contributing to underutilization include uncertainty that prophylaxis reduces clinically relevant events, as well as questions about the best form of prophylaxis. We sought to determine whether prophylaxis decreases clinically significant events and to answer whether unfractionated heparin (UFH) or low molecular weight heparin (LMWH) is either more effective or safer.
The MEDLINE, EMBASE, CINAHL, and Cochrane databases were searched through June 2008. Relevant bibliographies and conference proceedings were reviewed and LMWH manufacturers were contacted.
Randomized trials comparing UFH or LMWH to control, as well as head-to-head comparisons of UFH to LMWH in general medicine patients.
End points of deep venous thrombosis (DVT), proximal or symptomatic DVT, pulmonary embolism, mortality, bleeding, and thrombocytopenia were extracted from individual trials. Pooled relative risks were calculated using random effects modeling.
We identified 8 trials comparing prophylaxis to control, and 6 trials comparing UFH to LMWH. Prophylaxis reduced DVT (relative risk [RR] = 0.55; 95% confidence interval [CI]: 0.36-0.92), proximal DVT (RR = 0.46; 95% CI: 0.31-0.69), and pulmonary embolism (RR = 0.70; 95% CI: 0.53-0.93). Prophylaxis increased the risk of any bleeding (RR = 1.54; 95% CI: 1.15-2.06) but not major bleeding. Across trials comparing LMWH to UFH, there were no differences for any outcome.
Among medical patients, pharmacologic prophylaxis reduced the risk of thromboembolism without increasing risk of major bleeding. The current literature does not demonstrate superior efficacy of UFH or LMWH.
指南推荐对住院内科患者中血栓栓塞风险增加者进行药物预防。尽管有这些推荐，但多项研究表明预防措施未得到充分利用。导致未充分利用的因素包括对预防措施能否减少临床相关事件存在不确定性，以及关于最佳预防形式的问题。我们试图确定预防措施是否能减少具有临床意义的事件，并回答普通肝素（UFH）或低分子量肝素（LMWH）哪种更有效或更安全。
检索了截至2008年6月的MEDLINE、EMBASE、CINAHL和Cochrane数据库。查阅了相关参考文献和会议论文集，并联系了LMWH制造商。
比较UFH或LMWH与对照组的随机试验，以及普通内科患者中UFH与LMWH的直接比较。
从各个试验中提取深静脉血栓形成（DVT）、近端或症状性DVT、肺栓塞、死亡率、出血和血小板减少症的终点指标。使用随机效应模型计算合并相对风险。
我们确定了8项比较预防措施与对照组的试验，以及6项比较UFH与LMWH的试验。预防措施降低了DVT（相对风险[RR]=0.55；95%置信区间[CI]：0.36 - 0.92）、近端DVT（RR = 0.46；95% CI：0.31 - 0.69）和肺栓塞（RR = 0.70；95% CI：0.53 - 0.93）的风险。预防措施增加了任何出血的风险（RR = 1.54；95% CI：1.15 - 2.06），但未增加大出血风险。在比较LMWH与UFH的试验中，任何结局均无差异。
在内科患者中，药物预防措施降低了血栓栓塞风险，且未增加大出血风险。当前文献未显示UFH或LMWH具有更优疗效。
