A continuous heparin infusion does not prevent catheter-related thrombosis in infants post cardiac surgery

To determine whether a continuous infusion of heparin reduces the rate of catheter-related thrombosis in neonates and infants post cardiac surgery. Central venous and intracardiac catheters are used routinely in postoperative pediatric cardiac patients. Catheter-related thrombosis occurs in 8% to 45% of pediatric patients with central venous catheters.Single-center, randomized, placebo-controlled, double-blinded trial.Cardiovascular intensive care unit, university-affiliated children's hospital.Children <1 yr of age recovering from cardiac surgery.Patients were randomized to receive either continuous heparin at 10 units/kg/hr or placebo. The primary end point was catheter-related thrombosis as assessed by serial ultrasonography.Study enrollment was discontinued early based on results from an interim futility analysis. Ninety subjects were enrolled and received the study drug (heparin, 53; placebo, 37). The catheter-related thrombosis rate in the heparin group, compared with the placebo group, was 15% vs. 16% (p = .89). Subjects in the heparin group had a higher mean partial thromboplastin time (52 secs vs. 42 secs, p = .001), and this difference was greater for those aged <30 days (64 secs vs. 43 secs, p = .008). Catheters in place > or = 7 days had both a greater risk of thrombus formation (odds ratio, 4.3; p = .02) and catheter malfunction (odds ratio, 11.2; p = .008). We observed no significant differences in other outcome measures or in the frequency of adverse events.A continuous infusion of heparin at 10 units/kg/hr was safe but did not reduce catheter-related thrombus formation. Heparin at this dose caused an increase in partial thromboplastin time values, which, unexpectedly, was more pronounced in neonates.