Balancing safety and efficacy: Assessment of a weight-based, anti-Xa-guided enoxaparin venous thromboembolism prophylaxis dosing strategy for traumatic brain injury patients.

BACKGROUND

Patients with traumatic brain injury (TBI) with intracranial hemorrhage (ICH) are at high risk for venous thromboembolism (VTE) but are also prone to hemorrhagic progression. The efficacy and safety of weight-based, anti-Xa-guided enoxaparin dosing for patients with ICH are unknown. Therefore, this study aimed to compare fixed chemoprophylaxis versus weight-based, anti-Xa-guided enoxaparin dosing in the setting of ICH, hypothesizing reduced VTE incidence with similar ICH progression with weight-based, anti-Xa-guided dosing.

METHODS

This was a retrospective pre-post, quasi-experimental study conducted at a single, academic, Level I trauma center. Adult TBI patients admitted from December 2017 to May 2023 with ICH identified on computed tomography imaging who received at least 24 hours of chemoprophylaxis were included. A weight-based, anti-Xa-guided enoxaparin arm was compared with fixed doses of enoxaparin (40 mg) daily or unfractionated heparin (5,000 units) two to three times daily. Treatment groups were compared using a 1:1 propensity score matching (PSM), which matched for demographics and injury profile.

RESULTS

Of 831 included patients, 252 PSM cohorts were compared. A significantly lower incidence of VTE was observed in the anti-Xa-guided cohort (2.4% vs. 6.4%; p = 0.029), while radiographic ICH progression was equivalent between the two cohorts (4.4% vs. 4.4%; p = 0.99). A subgroup PSM analysis comparing 208 patients each from the anti-Xa-guided versus enoxaparin-only control cohort also demonstrated a significantly lower incidence of VTE with the anti-Xa-guided treatment (1.4% vs. 5.8%; p = 0.032) with no difference in radiographic ICH progression (4.3% vs. 2.4%; p = 0.28).

CONCLUSION

Weight-based, anti-Xa-guided enoxaparin dosing was associated with reduced VTE incidence without increased ICH progression in TBI patients with existing ICH.

LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.