Development of standards for stored autologous blood transfusion

Standards for stored autologous blood transfusion were established recently based on the clinical experience and research data for 140 autologous blood transfusions, which have been carried out in orthognathic surgery patients between 1985 and 1992 at the First Department of Oral and Maxillofacial Surgery, Kagoshima University Dental Hospital, Japan. Regarding standards designed to avoid anemia after phlebotomy, one time collection volume was decided using the following formula: predicted Hb level after collection=(circulating blood volume-one time collection volume) ÷circulating blood volume×Hb level before collection ≥10 g/dl. Fifteen female patients with mandibular prognathism were studied hematologically following a 400 ml autologous blood collection and a transfusion to evaluate the efficiency of this new standard.Two units of whole blood were collected 15 days before each patient's operation. All units of collected blood were transfused without homologous blood transfusion. RBCs, Hb and Hct, which were reduced after the phlebotomy, normalized the day before operation. The rate of reticulocytes was tended to increase during the period of blood storage and for one week after operation. The iron level in the serum was minimum on the day following operation, suggesting the need for postoperative iron supplementation. Increased serum erythropoietin levels, similar to reticulocytes, showed high erythropoietic activity from the first day following the phlebotomy to the postoperative period. There were no differences between the actual minimum Hb level and the predicted Hb level after blood collection of 400 ml. The Hb level on the first day after operation was significantly higher than the calculated Hb level on the same day without blood transfusion (p<0.01).These results suggested the usefulness of our standards.