Background
Providing safe blood for transfusion remains a challenge despite advances in preventing transmission of hepatitis B, hepatitis C, AIDS/HIV, West Nile virus (WNV), and transfusion-transmitted bacterial infection. Human errors such as misidentifying patients and drawing blood samples from the wrong person present much more of a risk than transmissible diseases.
Additional risks include transfusion related acute lung injury (TRALI), a potentially life-threatening condition with symptoms such as dyspnea, fever, and hypotension occurring within hours of transfusion, and also transfusion-associated immunomodulation, which may suppress the immune response and cause adverse effects such a small increase in the risk of postoperative infection.
Other risks such as variant Creutzfeldt-Jakob disease (vCJD), an invariably fatal disease, remain worrisome. Blood centers worldwide have instituted criteria to reject donors who may have been exposed to vCJD. Screening for transmissible diseases and deferral policies for vCJD designed to improve safety have contributed to shrinking the donor pool. Blood shortages exist in the United States and worldwide. In many industrialized countries 5% or less of the eligible population are blood donors.
As a result, the global medical community has increasingly moved from allogenic blood (blood collected from another person) towards autologous infusion, in which patients receive their own blood. Another impetus for autologous transfusion is the position of Jehovah's Witnesses on blood transfusions. For religious reasons, Jehovah's Witnesses will not accept any allogeneic transfusions from a volunteer's blood donation, but may accept the use of autologous blood salvaged during surgery to restore their blood volume and homeostasis during the course of an operation, although not autologous blood donated beforehand.
Read more about this topic: Intraoperative Blood Salvage
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