Blood banks are laboratory centers that are responsible for the collection, processing, typing, safety and storage of blood for research and medical purposes. Most blood collected for medical use is transfused into patients who need blood because of trauma, for surgery or as therapeutic treatment of diseases, such as sickle cell disease and anemia and as a result of chemotherapy In all, 23 million units of blood are transfused annually, according to the American Association of Blood Banks (AABB).
Blood banks collect and store blood for the community.
Whole Blood Collection
According to the American Association of Blood Banks, eight million people volunteer each year to donate blood. At a local blood bank---or blood drive sponsored by a blood bank---one unit (about a pint) of whole blood is collected from an arm vein into a collection bag. Whole blood is usually separated out later by the laboratory into its component parts for use: white blood cells, red blood cells, plasma and platelets. These usually are pooled with components of similar types for use in the community.
Autologous and Apheresis Donation
Blood banks usually supervise autologous donations, which are whole-blood donations from an individual for later use by that individual. Autologous donations are usually given in advance of that person having surgery or a medical procedure for which there is a possibility the person will need a transfusion.
Some blood banks collect only red blood cells, platelets or both, using a process called apheresis. In apheresis, the blood is collected from the arm, filtered for the specific cells being donated, with the rest immediately filtered back into the donor.
Donor Screening
Blood banks screen donors for safety before ever accepting any blood from them. Blood bank staff ask questions about the donor's heath history, information about possible exposure to infections or pregnancy and take the potential donor's blood pressure, pulse and temperature. Any abnormalities will cause the staff to defer the donor--to disqualify them from donation. The deferred donor is then added to a registry that the blood bank maintains. A donor deferment may be temporary (in the case of a reversible condition, such as the donor has a cold or has recently gotten a tattoo) or permanent (such as donor who is HIV positive), but, in all cases, is enforced to protect the health and safety of the donor and the blood supply.
Blood Safety
Blood banks are responsible for testing and protecting the safety of the blood supply. Aside from manually screening donors, blood banks test all donated blood for ABO and Rh group (known as "blood types"), as well as for multiple transmissible diseases and contamination. Blood banks work to ensure that the blood supply is free of infection, unexpected antibodies present (from pregnancy or past donor transfusions) and ready for use. Diseases tested for in U.S. based blood banks include hepatitis B, hepatitis C, HIV-1 and HIV-2, human T-lymphotropic virus, and syphilis. Tests that aren't required, but commonly performed, also screen for West Nile virus and Chagas disease.
Blood banks work to ensure a continuously available safe blood supply by properly storing it--keeping the blood components labeled and refrigerated or frozen.
Research
Many blood banks are also centers of research, using a portion of donated blood to further study blood cells, diseases and improve blood safety and storage.
Several major blood banks are also involved in cord-blood research, a relatively new area of blood research that has the potential to treat previously untreatable diseases and as a replacement for bone-marrow transplants. Cord blood, which contains stem cells, is collected from volunteer birthing mothers who donate their newborns' placentas and umbilical cords.
