Weight-Based Dosing for Venous Thromboembolism Prophylaxis in Spinal Trauma Patients Appears Safe

Venous thromboembolism (VTE) is a substantial cause of morbidity and mortality in trauma patients. VTE prophylaxis (VTEP) initiation is often delayed in certain patients due to the perceived risk of bleeding complications. Our VTEP guideline was changed from fixed-dosing to a weight-based dosing strategy using enoxaparin in June 2019. We investigated the rate of postoperative bleeding complications with a weight-based and a standard dosing protocol in traumatic spine injury patients requiring surgical stabilization.

A retrospective pre-post cohort study using an institutional trauma database was conducted, comparing bleeding complications between fixed and weight-based VTEP protocols. Patients undergoing surgical stabilization of a spine injury were included. The preintervention cohort received fixed-dose thromboprophylaxis (30 mg twice daily or 40 mg daily); the postcohort received weight-based thromboprophylaxis (0.5 mg/kg q12 h with anti-factor Xa monitoring). All patients received VTEP 24-48 h after surgery. International Classification of Diseases codes were used to identify bleeding complications.

There were 68 patients in the pregroup and 68 in the postgroup with comparable demographics. Incidence of bleeding complications in the pre- and postgroups were 2.94% and 0% respectively.

VTEP initiated 24-48 h after surgical stabilization of a spine fracture using a weight-based dosing strategy and has a similar rate of bleeding complications as a standard dose protocol. Our study is limited by the low overall incidence of bleeding complications and small sample size. These findings could be validated by a larger multicenter trial.