Blood procurement is a vital national priority that is met in the United States (U.S.) by volunteer donors and a pluralistic blood collection program that includes the American Red Cross, independent community blood centers, and hospitals. Approximately 12 million units of whole blood are collected from approximately 9 million donors annually.1,2 Recruitment of donors is preceded by a medical history and limited physical examination. The donated blood is subjected to tests of blood type, red cell antibodies, and infectious agents that may be transmitted by blood transfusion. In some cases, collection of red cells, platelets, leukocytes, or plasma is achieved by hemapheresis. Plasma for the subsequent manufacture of derivatives such as albumin and intravenous immunoglobulin (IVIG) is obtained from paid donors by for-profit organizations different from those that collect whole blood and prepare blood components. The meticulous attention to donor risk characteristics and the use of sensitive assays to detect infectious agents that may be transmitted by blood have greatly improved the safety of blood.
It is widely accepted that red blood cell (RBC) transfusions save lives and prevent ischemic-related morbidity in severely hemorrhaging patients and those with acute anemia (hemoglobin [Hb] <60 g/L). When a patient’s Hb level exceeds 100 g/L, oxygen delivery and consumption do not necessarily increase with RBC transfusions. For patients in the 60 to 100 g/L Hb “gray zone,” the benefit of a transfusion will depend on a patient’s clinical status, and should be weighed against the inherent risks of allogeneic blood, but primarily these patients do not benefit from transfusion (see later in this chapter).
These risks include adverse reactions, which occur in up to 3% of transfusions. Transfusion-associated circulatory overload (TACO) is the number one cause of transfusion-related fatalities, and new pathogens causing transfusion-transmitted infections continue to pose a threat to the blood supply. TACO overload is often not recognized but has been associated with increased morbidity and prolonged lengths of hospital stay.
As the older population grows in the U.S., the demand for blood will increase, even as the donor population declines. Patient blood management efforts are growing in popularity as hospitals grapple with the risks and costs associated with transfusion. The implementation of evidence-based practice is the best way to benefit patients and minimize the risks of transfusion.
Acronyms and Abbreviations:
AABB, American Association of Blood Banks; AHTR, acute hemolytic transfusion reactions; APACHE II, Acute Physiology and Chronic Health Evaluation II; ARDS, acute respiratory distress syndrome; ARV, antiretroviral; ATRs, allergic transfusion reactions; BCHS, British Committee for Standards in Haematology; BNP, B-type natriuretic peptide; CI, confidence interval; CMV, cytomegalovirus; DAT, direct antiglobulin test; DHTRs, delayed hemolytic transfusion reactions; ESAs, erythropoiesis-stimulating agents; FDA, Food and Drug Administration; FFP, fresh frozen plasma; FNHTRs, febrile non-hemolytic transfusion reactions; FOCUS, Functional Outcomes in Cardiovascular Patients Undergoing Surgical Hip Fracture Repair; FP, frozen plasma; GI, gastrointestinal; GVHD, graft-versus-host disease; Hb, hemoglobin; Hct, hematocrit; HLA, human leukocyte antigen; HPC-A, hematopoietic progenitor cells ...