HEMOFILTRATION DURING CARDIOPULMONARY BYPASS - QUALITY ASSESSMENT OF HEMOCONCENTRATED BLOOD

Hemofiltration is often used during cardiopulmonary bypass (CPB) for w ater removal. In a prospective random study 11 patients undergoing ele ctive coronary artery surgery with hemofiltration during CPB were obse rved and compared to 11 patients without filtration. The quantitative and qualitative aspects of blood before and after filtration while sti ll on CPB and until the first postoperative day were assessed. Intra- and postoperative volume requirements, standard hematology and chemist ry, as well as hemolysis, complement activation, and coagulation facto rs were analysed at nine sequential points in time. Results: There wer e no significant differences in pre- and postoperative patient data be tween the two groups except that the majority of patients in the study group (55 %) were anti-coagulated and required a significantly longer CPB time with higher doses of protamine and had higher postoperative drainage (2.9 vs. 1.4 L). Intra- and postoperative hemoglobin concentr ations, transfusion and volume requirements were similar in both group s. 927 ml of plasma water were filtered during CPB within 4 min 20 s w ithout hemodynamic changes or electrolyte imbalance. Hemoglobin and pr otein concentrations increased significantly during hemofiltration (Hb up 3.6 g/dl). Hemolysis and activated complement fractions were eleva ted during CPB but showed no further increase during filtration; in co ntrast C4a, C5a, and prothrombin F1 + 2 increased significantly after cessation of CPB. In conclusion, hemofiltration during CPB is a safe a nd efficient method for water removal and for concentration of red blo od cells and proteins without adverse effects on the patient's hemodyn amics, blood quality, and volume requirements. More especially, no neg ative influence of hemofiltration could be determined with regard to a ctivation of the coagulation and complement system.