BACKGROUND: This study investigated the clinical usefulness of an autotransfusion of drained blood using postoperative wound drainage and a reinfusion system to reduce the allogenic blood transfusion without complications.

METHODS: Eighty patients were allocated randomly to either a control group using a standard drainage system or an autotransfusion group using postoperative wound drainage and a reinfusion system. The collection period was 12 h, and the drainage blood retransfused after 6 h, or a maximum of 500 ml of blood was collected after connecting the reinfusion system. Immediately before reinfusion, blood samples were taken from the reinfusion system and analyzed for the functional and metabolic status of the drained blood and compared with the preoperative values of patient. The hemoglobin level, blood loss, allogenic blood requirement and transfusion-related complications were assessed.

RESULTS: The drained blood had lower hematological values, a prolonged PT and aPTT, a lower fibrinogen, and metabolic acidotic status than the preoperative values of the patients. There were no significant differences in the amount of blood loss compared with the control group. However, the autotransfusion group required significantly less allogenic blood (almost 20% less) without significant complications.

CONCLUSIONS: Autotransfusion by reinfusion with drained blood in bilateral total knee arthroplasty reduces the allogenic blood requirement without significant complications.