Evaluation of Enoxaparin Dosing in Infants Greater Than 2 to 6 Months of Age, a Pre and Post Quasi Experiment.

OBJECTIVE

Enoxaparin is regularly used to treat thromboembolism in children. Numerous retrospective studies suggest that infants and young children require higher enoxaparin doses to achieve therapeutic anti-factor Xa (AXA) concentration of 0.5 to 1.0 units/mL compared with adults.

METHODS

This is a retrospective analysis of pre- and post-implementation of an increased initial dose of enoxaparin (1.2 mg/kg every 12 hours) for infants between 2 and 6 months of age. The objective is to compare the number of dose adjustments needed to achieve therapeutic AXA.

RESULTS

A total of 64 patients were included 30 pre- and 34 post-guideline groups. In both the pre- and post-guideline dosing groups the number of dose adjustments required to achieve therapeutic AXA when adjusted per the ACCP guidelines was a median of 1 (p = 0.35). However, the first initial AXA was 0.3 units/mL in the pre-guideline group and 0.48 units/mL in the post-guideline group (p = 0.07). There were no documented instances of major bleeding events in either group.

CONCLUSION

The results support the recommendation of an increased enoxaparin starting dose for therapeutic anticoagulation in the described patient population at the study site. A large prospective study is needed to determine specific dose recommendations that will achieve therapeutic AXA concentrations for the majority of infants and children of all ages.