Heparin Use in Pediatric Bypass—Empirical Regimen (ACT) vs. Heparin Concentration: A Multicenter Trial

There are two common approaches to heparin administration for pediatric bypass: one involves the empirical dosing of heparin based on the activated clotting time (ACT), and the other on heparin concentration. It has been observed that heparin requirements are substantially greater when maintaining a concentration as opposed to an ACT. This study gathered heparin administration data from five pediatric centers, two using an empirical regimen and ACT technique and three using heparin concentration as measured by the Heparin Management System (HMS). All patients less than or equal to 20 kg were evaluated and grouped by technique. There were 49 patients in the HMS group and 46 in the ACT group. There was no significant difference between groups for patient weight, bypass time, postheparin ACT, bypass ACT, protamine dose, or 24-h blood loss (mL/kg/24). There was a significant difference ( p < .01) for prime heparin (4.7 ± 1.3 units/cc HMS vs. 1.9 ± 0.4 units/cc ACT), heparin loading dose (476.5 ± 175.3 units/kg HMS vs. 384.6 ± 54.3 units/kg ACT), and total heparin (16.6 ± 6.7 units/kg/min HMS vs. 9.5 ± 5.9 units/kg/min ACT). The use of the HMS for heparin management in pediatric bypass required more heparin but no difference in protamine use or 24-h blood loss.