Quality of drainage blood: survival of red cells after re-transfusion and content of free hemoglobin and potassium.

Re-transfusion of drainage blood is widely used in orthopedic surgery, but objective evidence of the efficacy of re-transfusion of drainage blood in view of post-transfusion survival of RBC has not been given so far. With this study we wanted to evaluate the efficacy and safety of transfusion of drainage blood collected with HandyVac autotransfusion system. In 7 patients red cells in drainage blood were labeled with biotin and percentage of labeled red cells in circulation were determined immediately after re-transfusion, and during 10 days after surgery. To assess further unwanted side-effects of re-transfusion of drainage blood potassium and free hemoglobin were determined in the collected blood. Ten days after re-transfusion at mean 78.9% of drainage-blood derived RBC were found in circulation. Free hemoglobin in drainage blood ranged from 16.8 to 59.2 mg/dL; potassium in drainage blood ranged from 3.84 to 4.52 mmol/L. Our results suggest that re-transfusion of drainage blood collected with HandyVac autotransfusion system is an efficient procedure that seems to be safe in view of free hemoglobin and potassium in the product.