Late VTE Chemoprophylaxis Increases Risk of Serious Complications in Patients with Traumatic Spinal Injury

Morgan G, Karyssa MN, Wilson K, et al. Late Venous Thromboembolism Chemoprophylaxis and Increased Risk of Deep Venous Thrombosis, Pulmonary Embolism, and Mortality in Patients with Traumatic Spinal Injury. J Am Coll Surg. March 2026.

Optimal timing of venous thromboembolism chemoprophylaxis after traumatic spinal injury remains controversial due to bleeding concerns, particularly surrounding operative intervention. National-level mortality data evaluating delayed prophylaxis in this population are limited.

Authors performed a retrospective cohort study of the 2021 National Trauma Data Bank, including adult trauma patients with spinal injury and hospital length of stay >48 hours (n = 96,515). Patients were stratified by early (<48 hours; n = 63,051) versus late (≥48 hours; n = 33,464) chemoprophylaxis. Primary endpoints were deep vein thrombosis (DVT), pulmonary embolism, and in-hospital mortality. 

Multivariate logistic regression adjusted for age, gender, mechanism, severe regional Abbreviated Injury Scale scores (spine, thorax, abdomen ≥3), spine surgery, unplanned return to the operating room, and chemoprophylaxis type.

Late chemoprophylaxis was associated with higher rates of DVT (3.5% vs 1.3%), pulmonary embolism (1.8% vs 0.8%), and mortality (5.4% vs 2.9%) (all p <0.0001). After adjustment, delayed prophylaxis remained independently associated with DVT (OR 2.3, 95% CI 2.102–2.553), pulmonary embolism (OR 1.7, 95% CI 1.529–1.967), and mortality (OR 1.9, 95% CI 1.807–2.092) (all p <0.0001). 

Spine surgery was the strongest predictor of delayed initiation (OR 3.3, 95% CI 3.208–3.433). Increased thromboembolic risk with delayed prophylaxis persisted across operative, isolated spine injury, and spinal cord injury subgroups.

For surgeons, these findings support early initiation when clinically feasible while highlighting the need for prospective evaluation of bleeding risk.