Original Article

Heparin Reversal in Children Following Cardiopulmonary Bypass

Department of Anesthesiology and Division of Cardiothoracic Surgery, The Children's Hospital, Denver, CO

^* Direct communications to: Dan R. Hydrick, 810 East Grand River, Brighton, MI 48115

Abstract

Inadequate or excessive doses of heparin and protamine during cardiopulmonary bypass (CPB) are associated with both theoretical and well-documented real complications. A simple and safe method of determining optimal doses of heparin and protamine has its place in pediatric cardiac surgery.

Use of a heparin dose-activated clotting time (ACT) response curve method was compared to an older arbitrarily fixed dose method of anticoagulation management for CPB in 85 infants and children. All patients were initially heparinized with 3 mg/kg heparin. In group 1, a two point dose-response curve, generated prior to CPB, was used to determine doses of incremental heparin during CPB and protamine following CPB. In group 2, fixed doses of incremental heparin (1.5 mg/kg each hr of CPB) and protamine (2:1 ratio of protamine to initial heparin dose) were administered.

Age, weight, and duration of CPB were similar in each group. Adequate maintenance of anticoagulation with heparin and its reversal with protamine were demonstrated by ACTs in each group. However, group 1 patients required 28% less heparin (P < 0.01) and 39% less protamine (P < 0.01) than did group 2 patients. The authors conclude that the dose-response curve provides a simple and reliable method to optimize anticoagulation management during CPB in pediatric patients.