Weight-based enoxaparin dosing and deep vein thrombosis in hospitalized trauma patients: A double-blind, randomized, pilot study

Venous thromboembolism is a cause of morbidity and mortality in trauma patients. Chemoprophylaxis with low-molecular-weight heparin at a standardized dose is recommended. Conventional chemoprophylaxis may be inadequate. We hypothesized that a weight-adjusted enoxaparin prophylaxis regimen would reduce the frequency of venous thromboembolism in hospitalized trauma patients and at 90-day follow-up. This prospective, randomized pilot study enrolled adult patients admitted to a level 1 trauma center between July 2013 and January 2015. Subjects were randomized to receive either standard (30 mg subcutaneously every 12 hours) or weight-based (0.5mg/kg subcutaneously every 12 hours) enoxaparin. Surveillance duplex ultrasound for lower extremity deep vein thrombosis was performed on hospital days 1, 3, and 7, and weekly thereafter. The primary outcome was deep vein thrombosis during hospitalization. Secondary outcomes included venous thromboembolism at 90 days and significant bleeding events. Two hundred thirty-four (124 standard, 110 weight-based) subjects were enrolled. There was no difference between standard and weight-based regarding age, body mass index, percentage female gender, injury severity score, or percentage that had surgery. There was a trend toward less in-hospital deep vein thrombosis in weight-based (12 [9.7%] standard vs 4 [3.6%] weight-based, P = .075). At 90 days, there was no difference in venous thromboembolism (12 [9.7%] standard vs 6 [5.5%] weight-based, P =.34). There was 1 bleeding event, which occurred in a standard subject. Weight-based enoxaparin dosing for venous thromboembolism chemoprophylaxis in trauma patients may provide better protection against venous thromboembolism than standard. A definitive study is necessary to determine whether weight-based dosing is superior to standard.