Alternatives to blood product transfusion in the critically ill: Erythropoietin

Abstract

To present information regarding the use of recombinant human erythropoietin (rHuEPO) to treat anemia in intensive care unit (ICU) patients Anemia is common in critically ill patients. Approximately 95% of patients have subnormal hemoglobin (Hb) values by day 3 of their ICU stay. ICU-associated anemia often requires replacement of red blood cells (RBCs) via transfusion. Recent surveys of ICU practice document that approximately 50% of ICU patients receive RBC transfusions. ICU-associated anemia is largely the result of the cumulative effects of blood loss and decreased RBC production. Blood loss in critically ill patients may be overt, occult, or due to phlebotomy. Decreased RBC production is the other major factor influencing the development of anemia. Decreased RBC production is due to the combined effects of abnormal iron metabolism, inappropriately low erythropoietin production, diminished response to erythropoietin, and direct suppression of RBC production. Inflammatory mediators play a pivotal role in the pathogenesis of decreased RBC production. Clinical trials have shown that, compared with nontreated subjects, rHuEPO-treated ICU patients will have increased serum erythropoietin concentrations, increased reticulocyte counts, and increased hemoglobin and hematocrit values and require fewer RBC transfusions. These clinical trials have not detected significant differences in outcomes in association with rHuEPO, however. rHuEPO can be used to increase hemoglobin and hematocrit values and decrease the number of RBC transfusions in ICU patients. Further investigation is necessary to identify the appropriate target population of ICU patients for treatment, to clarify the appropriate dosing schedule, and to ascertain whether such therapy has a positive impact on outcomes.