Unfractionated heparin using actual body weight without dose capping in obese pediatric patients—Subgroup analysis from an observational cohort study

To evaluate the correlation between an uncapped, actual body weight-based unfractionated heparin dosing strategy, we performed a body mass index-based subanalysis of a previously reported pediatric cohort. Nearly half (45%) of obese patients were supra-therapeutic on initial anti-FXa assessment. Obese patients achieved therapeutic anti-FXa significantly faster than nonobese patients (median 4 vs 12 hours, P =.0192) and were more likely to have any supra-therapeutic anti-FXa levels (77% vs 35%; P =.0021). There was no statistically significant difference in major or clinically relevant nonmajor bleeding rates between weight categories (P =.69). Prospective pediatric studies are warranted to confirm our findings.