Efficacy of currently recommended enoxaparin dosing titration for therapeutic use in neonates

Abstract

Specific Aims: To determine if current published enoxaparin dose titration recommendations are effective in achieving therapeutic anti-FXa concentrations on the first dose titration in neonates. Methods: Retrospective chart review included neonates (< 28 days old) who received therapeutic enoxaparin between 09/01/2018 to 09/01/2021. Patients on mechanical circulatory support (MCS) or renal replacement therapy (RRT) during or within 48 hours of enoxaparin therapy, or had a creatinine clearance (CrCl) < 30 ml/min/m2 were excluded. Primary objective analyzed correlation between age (preterm < 37 weeks gestation and term ≥ 37 weeks gestation) and anti-FXa concentrations after the first enoxaparin dose titration when following published titration guidelines in neonates. Secondary objective determined the frequency of anti-FXa concentration achievement after first enoxaparin dose titration. Results: Twenty-six patients were included for analysis, with 76.9% being full term infants. Between age and anti-FXa concentrations after the first dose titration, preterm correlation coefficient of -0.71 and 0.29 for term. Fifty percent of the subjects were not at a therapeutic anti- FXa concentration on their first draw. Of those, 62% reached therapeutic concentrations after their initial enoxaparin dose titration in accordance with the published guidelines. Conclusions: Due to the small sample size, it is unclear whether current enoxaparin dosing titration recommendations are adequate to achieve therapeutic anti-FXa concentrations after the first dose titration in neonates. Further studies should be conducted with larger sample sizes.