Influence of modified ultrafiltration on coagulation, fibrinolysis and blood loss in adult cardiac surgery

Objectives: Modified ultrafiltration (MUF) significantly reduce blood loss and transfusion requirements in pediatric cardiac surgery presumably by a reduction in inflammatory mediators which decrease the inflammatory axes and decrease the cross-activation of fibrinolysis and thrombosis. The influence of MUF on blood loss and homologous blood transfusion in adult cardiac surgery has not yet been determined. Furthermore, data about the influence on routine coagulation tests, platelet activation as well as the coagulation and fibrinolytic systems are limited. Methods: In a prospective randomized study 48 patients scheduled for elective myocardial revascularization were randomized into a control group (n = 16), a conventional ultrafiltration (CUF) group (n = 16) and a MUF group (n = 16). Perioperatively, serial blood samples were drawn at specific intervals to evaluate coagulation, fibrinolysis, and platelet function. Results: Neither the coagulation nor the fibrinolytic system was positively influenced by MUF or CUF. The routine clotting tests were comparable except for a significantly higher antithrombin III activity after MUF compared to the CUF control group persisting 24 h postoperatively. Platelet factor 4 activity and platelet counts showed no differences among the groups. MUF considerably reduced the postoperative blood loss (MUF, 6.4 +/- 1.7 ml/kg bw per 24 h vs. CUF, 9.2 +/- 2.5 ml/kg bw per 24 h (P = 0.003) vs. control, 8.9 +/- 2.2 ml/kg bw per 24 h (P = 0.008)) and allogeneic blood transfusion (MUF, 2.0 +/- 3.4 ml/kg bw per 24 h vs. CUF, 6.9 +/- 5.1 ml/kg bw per 24 h (P = 0.034) vs. control, 7.0 +/- 6.3 ml/kg bw per 24 h (P = 0.029)). Conclusions: MUF in adult cardiac surgery significantly reduces postoperative blood loss and transfusion requirements. The mechanism for reduced blood loss could not be elucidated in this study. (C) 2001 Elsevier Science B.V. All rights reserved.