D. Argandykov1, J. A. Proaño-Zamudio1, W. Rafaqat1, E. Lagazzi1, M. Abiad1, A. Renne1, C. Paranjape1, J. Hwabejire1 1Massachusetts General Hospital, Trauma, Emergency Surgery, And Surgical Critical Care, Boston, MA, USA
Introduction: Patients undergoing trauma-associated lower limb amputation have a markedly elevated risk of developing venous thromboembolism (VTE). Practice variation persists regarding the optimal pharmacologic agent for VTE prophylaxis in this patient population. The aim of this study was to compare the efficacy of unfractionated heparin (UH) and low-molecular-weight heparin (LWMH).
Methods: Using the 2013-2019 ACS-TQIP database, adult patients who underwent lower limb amputation and received VTE thromboprophylaxis were included. Patients were excluded if they died within 24 hours of admission or received no thromboprophylaxis. The primary outcome was the rate of VTE, defined as deep venous thrombosis or pulmonary embolism, and in-hospital mortality. Univariate and multivariate logistic regression were used to examine the independent relationship between the type of thromboprophylaxis and VTE.
Results: A total of 4,069 patients who underwent lower extremity amputation following trauma were included. The in-hospital mortality rate was 3.5%, and the overall rate of VTE was 8.5%. 3,122 (76.7%) patients received LMWH. Patients receiving UH had a higher injury severity score (ISS): 16 [10–24] vs. 13 [9–19], p<0.001), a higher rate of hemorrhage control laparotomies performed within 4 hours of admission (9.3% vs. 3.3%, p<0.001), and required a higher number of blood and blood products transfusions within 4 hours (p<0.001). Multivariate analysis adjusting for the patient- and injury-related characteristics showed LMWH has independently associated with a reduced rate of VTE events (aOR: 0.69 [0.53–0.89]) (table 1).
Conclusion: The incidence of VTE events among trauma patients undergoing lower limb amputation was high (8.5%). LMWH thromboprophylaxis was found to be superior to UH for VTE prevention and, therefore, should be the preferred pharmacologic agent for use in this patient population.