Proposal of an algorithm to help the choice of the best transfusion strategy.

Autologous blood donation (ABD) reduces both the real and perceived risks of allogeneic blood exposure, although wasted units increase overall costs. Wastage of autologous blood can be contained by using rational blood ordering and collection strategies. These identify procedures with transfusion requirements, utilizing ABD predeposit in patients undergoing surgery for which the need for blood transfusion has been clearly established, and where the average blood loss for each procedure has been determined. ABD programmes can be optimized by adopting a personalized approach for each individual patient. The predicted and tolerated blood loss is calculated for each patient, and the difference between the two determines the patient's transfusion need. Taking into account the type of surgery, time to surgery and the clinical condition of the patient, the best and most cost-conscious transfusion strategy can then be determined. Options include: reducing the blood loss pharmacologically, transfusing allogeneic blood, using autologous blood from a variety of techniques, using recombinant erythropoietin (epoetin alfa) to increment baseline haematocrit (Hct) or to increase the volume of predonated blood, and using blood substitutes in addition to autotransfusion techniques. Autotransfusion techniques available include ABD predeposit, normovolaemic haemodilution and perioperative salvage. ABD predeposit may be limited by the delay in the natural erythropoietic response to allow recovery of red cells collected. Together with adequate iron support, epoetin alfa accelerates recovery of the Hct and increases the tolerated blood loss. The availability and judicious use of these blood conservation strategies provide for both effective and cost-conscious blood transfusion strategies.