HEPARINIZED CARDIOPULMONARY BYPASS AND FULL HEPARIN DOSE MARGINALLY IMPROVE CLINICAL-PERFORMANCE

Background. The use of completely heparin coated cardiopulmonary bypas s circuits in combination with a reduced systemic heparin dose has pre viously been shown to reduce postoperative bleeding after cardiac oper ations. However, it has remained unknown whether this effect was relat ed to the improved biocompatibility of the heparin-treated surfaces pe r se or to the reduced exposure to circulating heparin. Therefore we i nvestigated patients undergoing heparin-coated extracorporeal circulat ion and full systemic heparinization. Methods. Two hundred seventeen p atients having first-time myocardial revascularization were prospectiv ely randomized either to a group in which a completely (''tip-to-tip'' ) heparin-coated circuit (Duraflo II) was used for perfusion (n = 107) or to a control group (n = 110) in which an uncoated, but otherwise i dentical, circuit was used. Full systemic heparinization was induced i n both groups (activated clotting time, >480 seconds). The postoperati ve blood loss, requirements for homologous blood transfusions, clinica l performance, and complications were recorded. Results. The amount of postoperative mediastinal drainage was nearly identical in the two gr oups. The mean 18-hour drainage was 694 +/- 313 mL in the heparin-coat ed group and 679 +/- 269 mL in the control group (p = not significant) . Three patients in the heparin-coated group and 6 patients in the con trol group received homologous red blood cell transfusions (p = not si gnificant). The incidence of postoperative atrial fibrillation was sig nificantly lower in the heparin-coated group (21.8%) than in the contr ol group (43.1%) (p = 0.002). Otherwise, there were no significant dif ferences in the extubation times, the incidence of perioperative myoca rdial infarction, the creatinine concentration, the incidence of neuro logic dysfunction, the progress in physical rehabilitation, or the hem oglobin concentration at discharge. Conclusions. The use of completely heparin coated cardiopulmonary bypass circuits and full systemic hepa rinization in patients undergoing coronary artery bypass procedures di d not reduce postoperative bleeding or change clinical performance, ex cept for a significant decrease in the incidence of postoperative atri al fibrillation.