SLR - March 2023 - Emily Stefanski, DPM
Title: A Prospective Randomized Controlled Trial Comparing Enoxaparin & Rivaroxaban for Venous Thromboembolism Prophylaxis in Orthopaedic TraumaReference: Mitchell JP, Streufert BD, Downes K, Chase CB, Mir HR. A Prospective Randomized Controlled Trial Comparing Enoxaparin & Rivaroxaban for Venous Thromboembolism Prophylaxis in Orthopaedic Trauma. J Orthop Trauma. 2022 Dec; 36(12):615-622.
Level of Evidence: II
Reviewed By: Emily Stefanski, DPM
Residency Program: Kent Hospital, Warwick, RI
Podiatric Relevance: An unfortunate and potentially catastrophic post-operative complication is venous thromboembolism (VTE) with the rates of deep vein thrombosis (DVT) cited at 2.8% and pulmonary embolism (PE) at 1.5%. Multiple pharmacologic agents have been used prophylactically and noted to be effective in reducing the incidence of VTEs following surgery, however the advantages and disadvantages of these different medications have long been debated. This study compares patient medication satisfaction and adherence with a prophylactic regimen of subcutaneously injected enoxaparin or oral rivaroxaban in patients with surgical orthopedic trauma.
Methods: This was a prospective, randomized, controlled trial of orthopedic trauma patients at a Level 1 trauma center. All 121 patients presented with an operative fracture and were initially prophylactically treated with the institutional protocol of mechanical compression and enoxaparin 30 mg twice daily unless medically contraindicated. At discharge, patients were randomized into group A (63 patients) receiving a 20-day course of 40 mg of enoxaparin daily or group B (58 patients) receiving 10mg of rivaroxaban once daily for 20 days, each followed by an identical 3-week course of once daily Aspirin. Outcomes included patient medication satisfaction and adherence, clinically important DVT, PE, major bleeding events, adverse reactions and cost to patients.
Results: Overall, 120 patients completed final analysis with one patient lost to follow up. Medication satisfaction and adherence were measured using the Treatment Satisfaction Questionnaire for Medication (TSQM-9) and Morisky Medication Adherence Scale (MMAS-8). Greater medication satisfaction was linked to group B. Medication adherence was noted to be good overall with 65.5% in group A and 67.7% in group B. A single DVT event was reported in group B at 6 weeks. Group A however has greater adverse events including injection site bruising (14.5%) and inability to self-administer medication (11%). Average medication cost for uninsured patients was noted to be $4/20 day supply for 10 mg rivaroxaban and $43.50/20 day supply of enoxaparin; otherwise direct patient cost varied based on insurance plan.
Conclusions: While protocols for postoperative prophylactic anticoagulation regimen following operative repair of lower leg fractures remain controversial, this study demonstrates higher patient satisfaction with an oral versus an injectable. This study did have some notable weaknesses: institutional protocol started all patients initially on enoxaparin which may confound drug efficacy; patient-reported surveys are subject to recall and participant bias; insurance plans lead to variability in direct patient costs. Overall, patients demonstrated similar adherence to both enoxaparin and rivaroxaban with no statistically significant difference in thrombotic or bleeding events. Patients were more satisfied with the oral medication and had fewer adverse reactions.