Retransfusion of suctioned blood during cardiopulmonary bypass impairs hemostasis.

In a previous study we observed extensive clotting and fibrinolysis in blood from the thoracic cavities during cardiopulmonary bypass. We hypothesized that retransfusion of this suctioned blood could impair hemostasis. In this prospective clinical study we investigated the effect of suctioned blood retransfusion on systemic blood activation and on postoperative hemostasis. During coronary artery bypass grafting in 40 patients, suctioned blood was collected separately. It then was retransfused to the patient at the end of the operation (n = 19), or it was retained (n = 21). During the study, 12 consecutive patients, randomized in two groups of 6, were analyzed for biochemical parameters indicating blood activation and clotting. The immediate and significant increase in circulating concentrations of thrombin-antithrombin III complex, tissue-type plasminogen activator, fibrin degradation products, and free plasma hemoglobin demonstrated the effect of suctioned blood retransfusion. Moreover, the increased concentrations of thrombin-antithrombin III complex and fibrin degradation products indicated renewed systemic clotting and fibrinolysis as a direct result of the retransfusion of suctioned blood. Concentrations of all indicators mentioned remained significantly lower in the retainment group. The clinical data showed that retainment of suctioned blood resulted in significantly decreased postoperative blood loss (822 mL in the retransfusion group versus 611 mL in the retainment group; p < 0.05) and similar or even reduced consumption of blood products (513 versus 414 mL red blood cell concentrate and 384 versus 150 mL single-donor plasma; both not significant). We conclude that retransfusion of highly activated suctioned blood during cardiopulmonary bypass exacerbates wound bleeding.