Patients who undergo surgical procedures require skillful management of their total red blood cell (RBC) mass in the preoperative and postoperative periods. Failure to maintain or restore adequate RBC mass in patients undergoing elective or emergency operations can lead to disastrous complications, including severe damage to the heart, kidneys, and brain, as well as death. Less severe complications include delayed recovery of physical and mental function, unnecessary loss of time from work and recreational activities, impaired quality of life, and less successful rehabilitation.
Currently, surgeons use a variety of methods for maintaining and restoring RBC mass, including allogeneic transfusions, transfusion of autologous blood obtained during the preoperative period, infusion of autologous blood salvaged during or immediately after a surgical procedure, and administration of iron. All of these approaches increase the cost of care and all of them, especially blood transfusions, carry risks. Thus, excessive blood replacement or preparation for blood replacement is undesirable. For these reasons, there is a clear need to define the appropriate uses of all blood management methods and to seek new methods of improving perioperative blood management. Recently, surgeons have started using recombinant human erythropoietin (Epoetin alfa) to increase their patients' total RBC mass before elective operations. Their experience indicates that Epoetin alfa is a potentially important addition to current methods of perioperative blood management.
The articles in this issue consider a number of aspects of perioperative blood management. Several manuscripts review problems associated with preoperative blood donation and autologous blood transfusions, including the observations that much preoperatively donated blood is not used and that there are potential complications of autologous blood transfusion, including infection and transfusion of mismatched blood. Some investigators have also suggested that patients who donate blood preoperatively are more likely to receive transfusions of their donated blood than they would be to receive allogeneic blood transfusions. Therefore, some of these patients may undergo unnecessary transfusions. In addition, harvesting and then discarding unused autologous blood is costly. Several studies show that a significant number of patients undergoing elective joint replacements do not need blood transfusions, and that the preoperative hemoglobin (Hb) level is the best predictor of the risk of transfusion. In particular, patients with preoperative Hb levels below 1 1 g/dL have a high risk of requiring a transfusion, while patients with preoperative Hb levels above 13 g/dL have a low risk of requiring transfusion. Patients with preoperative Hb levels between 1 1 and 13 g/dL have an intermediate risk of transfusion. Other work demonstrates that preoperative administration of Epoetin alfa increases Hb levels and decreases the risk of transfusion in anemic patients who undergo joint replacement surgery, without increasing the risk of thromboembolism.
Despite the apparent attractiveness of the use of Epoetin alfa, a number of questions remain concerning its use. The cost effectiveness of Epoetin alfa compared with other perioperative blood management methods has not been studied extensively, and other than anemic patients who undergo joint replacement surgery, the patient populations likely to benefit from perioperative Epoetin alfa have not been well defined. For example, there has been little reported experience with preoperative or postoperative Epoetin alfa use in surgical patients with musculoskeletal tumors, multiple traumatic injuries, or complex spine disorders. However, these patient populations do appear to include individuals who might benefit from Epoetin alfa.
Despite the limitations of current information concerning the clinical applications of Epoetin alfa, a number of factors suggest that Epoetin alfa treatment may be helpful in perioperative blood management. It does not have the risks of infection or donor/ recipient mismatch that exist with both allogeneic and autologous blood transfusions. It produces a relatively rapid increase in Hb and hematocrit in patients scheduled for elective surgery without apparent complications and, thereby, may decrease the risk of transfusion. It also offers the potential for accelerating the restoration of total RBC mass following surgery and, thus, accelerating recovery and rehabilitation. Clearly, these potential benefits justify further clinical investigation and definition of the role of Epoetin alfa in perioperative blood management for a variety of patient populations.