Changes in hemostasis during pediatric heart surgery:: Impact of a biocompatible heparin-coated perfusion system

Background. This study describes the response in hemostasis during open-heart surgery with cardiopulmonary bypass (CPB) in children (less than or equal to 10 kg) and tests the hypothesis that the use of a biocompatible perfusion system, in comparison with a conventional system, causes less hemostatic activation. Methods. Prospective, randomized, controlled clinical study. Forty consecutive children less than or equal to 10 kg were included and divided into two groups: group bioc. (n = 19) treated with a fully heparin-coated system, centrifugal pump, and a closed circuit, and group conv. (n = 21) treated with an uncoated system, roller pump, and a hard shell venous reservoir. Concentrations of plasma thrombin-antithrombin (TAT), D-dimer, tissue plasminogen activator antigen (t-PA ag), and the complex consisting of tissue plasminogen activator and its inhibitor plasminogen activator inhibitor-1 (t-PA-PAI-1) were measured. Results. The biochemical variables measured increased significantly in both groups during the study period. There was less activation of fibrinolysis during cardiopulmonary bypass (t-PA ag: p = 0.009) in patients treated with the biocompatible perfusion system than in patients treated with the conventional system. A trend in favor of the biocompatible system based on the D-dimer and TAT data (p = 0.07 for both measurements) was observed but no significant intergroup differences regarding these variables or t-PA-PAI-1 were found. Conclusions. Open-heart surgery with cardiopulmonary bypass in children (less than or equal to 10 kg) causes transient activation of the coagulation and fibrinolytic systems. This study demonstrates that the use of a biocompatible perfusion system results in a lower extent of activation of fibrinolysis during CPB than the use of a conventional system. (C) 2004 by The Society of Thoracic Surgeons.