Prevention of Venous Thromboembolism

Venous thromboembolism (VTE) is a major health problem, with at least 201,000 first-lifetime cases per year in the United state^.^,^' Of these patients, 25% die within 7 days of VTE onset, and for 20% death is so rapid that there is insufficient time for inter~ention.~~ Thus, for a substantial percentage of patients, the initial clinical presentation of VTE (e.g., pulmonary embolism [PE]) is ”sudden death.” Even for those patients surviving at least 1 week, however, observed survival after either deep vein thrombosis (DVT) or PE is significantly less than expected (Fig. 1). Moreover, after controlling for other comorbid diseases, survival after PE is significantly reduced for up to 3 months compared with survival after DVT al0ne.2~ Thus, VTE is a cause of death that is independent of other frequently present diseases (e.g., cancer, trauma, or paresis). Prevention of VTE is essential to improve survival. Despite improved prophylaxis regimen^,'^ however, the incidence of VTE has been relatively constant at about 1 per 1000 since 1979 (Fig. 2).50 The failure to reduce the incidence of VTE may be caused by several factors, including an increased number of persons at risk, failure to recognize persons at risk, and failure to modify risk factors or provide prophylaxis.*, This article outlines the risk factors for VTE among hospitalized patients, reviews the efficacy and safety of alternative prophylaxis regimens, and provides recommendations regarding the most suitable prophylaxis regimens based on the estimated risk. The primary goal of VTE prophylaxis is to prevent fatal PE. It is important to appreciate the relationship between