Acutely ill medical patients are at significant risk of developing venous thromboembolic (VTE) complications during or after their hospitalization. Venous thromboembolic events, such as proximal deep vein thrombosis (DVT) or pulmonary embolism (PE), place a high and unacceptable burden on health care resources, up to US$1.5 billion annually in the United States. However, the burden of VTE can be reduced by use of appropriate thromboprophylaxis. Prophylaxis of VTE with either a low-dose unfractionated heparin (UFH) or a low-molecular-weight heparin (LMWH) in medical inpatients is effective, well tolerated and cost-effective, compared with no prophylaxis. Low-molecular-weight heparins have a number of practical benefits over UFH, including once-daily subcutaneous injection and the potential to be used in the outpatient setting. These clinical advantages could translate to improved patient adherence to therapy and provide economic benefits, where LMWHs are more cost-effective compared with UFH.
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