Anemia and Red Blood Cell Transfusion: Advances in Critical Care.

Anemia is common in the intensive care unit (ICU), resulting in frequent administration of red blood cell (RBC) transfusions. Significant advances have been made in understanding the pathophysiology of anemia in the ICU, which is anemia of inflammation. This anemia is related to high hepcidin concentrations resulting in iron-restricted erythropoiesis, and decreased erythropoietin concentrations. A new hormone (erythroferrone) has been identified, which mediates hepcidin suppression to allow increased iron absorption and mobilization from iron stores. RBC transfusions are most commonly administered to ICU patients for treatment of anemia. All strategies to reduce anemia in the ICU should be implemented.