COMPARISON OF 3 BLOOD-PROCESSING TECHNIQUES DURING AND AFTER CARDIOPULMONARY BYPASS

The return of extracorporeal circuit blood at the termination of cardi opulmonary bypass is an important feature of blood conservation during open heart procedures. However, the relative benefits and disadvantag es of different circuit blood salvage methods remain unclear. Accordin gly, the purpose of this study was to examine whether quantifiable dif ferences exist between three different circuit blood-salvaging techniq ues: direct infusion, centrifugation, and ultrafiltration. Sixty patie nts with very similar preoperative characteristics were randomly assig ned to each of the three groups, and blood coagulation screens, plasma profiles, and respiratory function were determined at 20 minutes and at 6 and 18 hours after cardiopulmonary bypass. Early after cardiopulm onary bypass (20 minutes), the plasma colloid osmotic pressure and fib rinogen and platelet concentrations were significantly higher with ult rafiltration (p < 0.05) versus those observed for the other two method s. The plasma thromboplastin times were significantly (p < 0.05) longe r after cardiopulmonary bypass with centrifugation as compared to dire ct infusion and ultrafiltration. However, the coagulation profiles and plasma composition normalized by 18 hours after cardiopulmonary bypas s with all three blood-salvaging methods. There were no significant di fferences in terms of blood utilization or chest tube drainage over th e entire postoperative period among any of the circuit blood-salvaging methods. These results suggest that ultrafiltration of postcardiopulm onary circuit blood may preserve plasma colloid pressure and platelet concentration in the early postoperative period, but these differences do not persist. Thus, for routine cardiopulmonary bypass procedures, direct infusion, centrifugation, and ultrafiltration may all be satisf actory methods of circuit blood salvage.