A retrospective analysis of the effectiveness of low molecular weight heparin for venous thromboembolism prophylaxis in trauma patients

Abstract

Background: In trauma patients, Enoxaparin (a low molecular weight heparin, LMWH) prophylaxis for venous thromboembolism (VTE) risk reduction is unproven.

Methods: Cohort analysis conducted consisting of all trauma patients age >13 admitted to Level-I trauma center and hospitalized >48 hours. VTE risk determined by the Risk Assessment Profile. High risk patients received LMWH unless contraindicated, while low and moderate risk patients received LMWH at attending surgeon's discretion. Odds ratio for VTE by logistic regression. VTE incidence, relative risk (RR), and number needed to treat (NNT) to prevent deep vein thrombosis (DVT) or pulmonary embolism determined by risk category.

Results: Cohort consisted of 2,281 patients (1,211 low, 979 moderate, 91 high risks). VTE occured in 254 patients (11.1%). High-risk patients had significantly higher VTE incidence, odds ratio = 31.8 (P < .001). VTE was significantly reduced in high-risk patients receiving LMWH versus those who did not (.26 vs .53, P = .02). Among moderate and high risk, prophylactic LMWH reduced the incidence of pulmonary embolism (RR = .19, NNT = 40.4, P = .01), and trended toward reduced DVT incidence (RR = .81, NNT = 27.3, P = .15). LMWH lowered DVT incidence (RR = .52, NNT = 4.1, P = .03) in high risk patients.

Conclusion: Prophylactic LMWH is associated with reduction of VTE in trauma patients.

Keywords: Deep vein thrombosis; Low molecular weight heparin; Pulmonary embolism; Trauma; Venous thromboembolism.