No Time for Clots: Protocolizing Enoxaparin in Trauma Patients

Venous thromboembolism (VTE) remains a significant complication following traumatic injury. Despite Western Trauma Association (WTA) 2020 guidance recommending enoxaparin 40mg every 12 hours for VTE prophylaxis, practice variation persists. In April 2024, Novant Health trauma facilities implemented a standardized trauma enoxaparin protocol aligning with WTA dosing, with defined modifications for bleeding risk, renal impairment, advanced age, low body weight (<50kg), and traumatic brain/spinal cord injury (TBI/SCI). This study evaluated its impact on dosing adherence, VTE outcomes, bleeding, and timing of prophylaxis.

This retrospective, multicenter, cohort study included adult trauma patients receiving prophylactic enoxaparin at Novant Health facilities from December 2021 to June 2025. Patients receiving therapeutic anticoagulation, with ESRD, pregnant, incarcerated, or lacking data were excluded. The primary outcome was inpatient VTE events. Secondary outcomes included protocol adherence, timing of prophylaxis initiation, major bleeding, anti-Xa utilization, and length of stay. Non-parametric tests were used for continuous variables and chi-square testing for categorical data; significance was defined as p<0.05.

A total of 148 patients were included with 74 patients in each cohort. Post-protocol patients had higher red-level trauma activations (39% vs. 11%) and greater TBI/SCI events (42% vs. 22%). Inpatient VTE rates remained low and similar between both cohorts (4% vs. 1%) despite higher acuity in the post-protocol cohort. Use of guideline-recommended enoxaparin 40mg every 12 hours increased substantially following protocol implementation (43% vs. 12%). Time to prophylaxis initiation was longer post-protocol (40 vs. 16 hours). No increase in major bleeding occurred. Anti-Xa monitoring increased (11% vs. 1%) and all TBI/SCI patients received appropriate prophylaxis. Hospital length of stay was longer post-protocol (7 vs. 4 days), consistent with higher injury severity.

A standardized trauma enoxaparin protocol significantly improved adherence to evidence-based dosing without increasing bleeding events and maintained low VTE rates despite treating a more critically injured population. Findings support continued system-wide protocol use to optimize thromboprophylaxis in trauma patients.