Bivalirudin anticoagulation in neonates and infants undergoing cardiac surgery

Abstract

Objectives: To determine the dosage of bivalirudin as the anticoagulant for cardiac surgery in neonates and infants.

Design: Pilot study.

Setting: Tertiary-care hospital.

Participants: Twenty-five neonates and infants with congenital heart disease (CHD) undergoing cardiac surgery.

Interventions: The children received a 1 mg/kg bivalirudin bolus followed by a 2.5 mg/kg/h infusion as the anticoagulant for cardiac surgery. The dose was adjusted subsequently to maintain an activated clotting time (ACT) >480 s.

Measurements and main results: The mean age and weight were 5.3 months and 5.2 kg, respectively. Out of the 25 children, 16 were cyanotic. Baseline rotational thromboelastometry (ROTEM) (Tem Innovations GmbH, Munich, Germany) analysis revealed an underlying coagulation defect across EXTEM, INTEM, FIBTEM, and ADPTEM parameters. The dose of anticoagulant required was 1 mg/kg, followed by a 2.2 ± 0.4 mg/kg/h infusion. Only 1 child required an additional bolus dose. The ACT remained elevated for 4 hours after discontinuation of infusion. The mean 24-h postoperative chest tube drainage was 92 ± 36 mL. Excessive bleeding occurred in 4 children, 1 of whom required re-exploration. The platelet count remained low for 5 days, and, postoperatively, the prothrombin time and activated partial thromboplastin time remained low for 2 days.

Conclusions: Effective anticoagulation was achieved with bivalirudin in the neonates and infants undergoing cardiac surgery. The dose required to maintain an ACT >480 s was 1.0 mg/kg, followed by 2.2 ± 0.4 mg/kg/h. The ACT remained elevated for 4 h after the discontinuation of bivalirudin infusion, resulting in an increased chest-tube output in some patients. Randomized, controlled trials are needed to further evaluate the safety of bivalirudin in the neonates and infants with complex congenital heart disease undergoing cardiac surgery with cardiopulmonary bypass.

Keywords: Bivalirudin; Coagulation monitoring; Direct thrombin inhibitors; Heparin alternatives; Pediatric cardiac surgery.