The effects of preoperative autologous donations on perioperative blood levels.

The purpose of this study was to evaluate the blood levels of patients preparing for total knee arthroplasty (TKA) who were enrolled in a preoperative autologous donation program. The charts and hospital records of 70 consecutive patients who underwent primary unilateral TKA between 2000 and 2002 were retrospectively reviewed. Study participants were instructed to donate one unit of blood approximately 4 weeks prior to surgery. Predonation and preoperative hemoglobin levels were assessed throughout the study and transfusion requirements were recorded. Transfusions were administered only when warranted by clinical symptoms. The mean initial (predonation) hemoglobin concentration was 14.1 g/dL. The mean number of days donations were made prior to surgery was 13 +/- 3.3 days. Prior to surgery, the average hemoglobin concentration dropped to 12.8 g/dL. Fifty (71%) patients had a hemoglobin value > 13.0 g/dL prior to their autologous donation, but only 30 (43%) patients had blood levels > or = 13.0 g/dL following blood donation. Postoperatively, the mean hemoglobin concentration in the recovery room was 11.6 g/dL and dropped to a nadir of 10.8 g/dL on postoperative day 3. Overall, 91% of patients required autologous blood transfusion following TKA but no patients required allogeneic blood transfusions. Preoperative autologous donation was associated with a decrease in preoperative hemoglobin levels and with a high rate of autologous transfusion based on clinical symptoms of postoperative anemia.