Prevention of venous thromboembolism in hospitalized medical patients: addressing some practical questions

PURPOSE OF REVIEW: To demonstrate that venous thromboembolism is an important and common problem in hospitalized medical patients; to outline anticoagulant prophylaxis management options and the evidence for efficacy and safety; and to identify medical patients in whom anticoagulant prophylaxis should be considered. RECENT FINDINGS: In at-risk medical patients who do not receive anticoagulant prophylaxis, the incidence of deep vein thrombosis is 10.5-14.9%. Prophylaxis with low-dose anticoagulant therapy confers a 57% reduction in the risk for symptomatic pulmonary embolism (relative risk, 0.43; 95% confidence interval: 0.26-0.71), a 62% reduction in the risk for fatal pulmonary embolism (relative risk, 0.38; 95% confidence interval: 0.21-0.69), and a 53% reduction in the risk for symptomatic deep vein thrombosis (relative risk, 0.47; 95% confidence interval: 0.22-1.00). Anticoagulant prophylaxis is also associated with a nonsignificant increased risk for major bleeding (relative risk, 1.32; 95% confidence interval: 0.73-2.37). Risk factors for venous thromboembolism and bleeding in medical patients have been proposed and may help identify patients in whom anticoagulant prophylaxis is indicated or contraindicated. However, validated risk-stratifications schemes are lacking. SUMMARY: Among hospitalized medical patients, randomized trials have established an acceptable therapeutic benefit-to-risk ratio of anticoagulant prophylaxis to reduce the incidence of clinically silent and symptomatic venous thromboembolism, including a reduction in the incidence of fatal pulmonary embolism. Additional research is needed to identify patients who would benefit most from anticoagulant prophylaxis.