■ Less anticoagulant and preservative in a single unit of WB (+60 ml) than combinations of RBC, fresh frozen plasma (FFP) and platelets (+200 ml) with less overall dilution and potential hemostatic impact.
■ Hemostatic function is better preserved in WB for up to one to two weeks, even with refrigeration.3
■ Accumulating evidence suggests that cold-stored platelets (similar to cold WB) have preserved function even with cold-induced changes in platelet shape and a shorter potential life span, while continuing to be adequate for acute hemorrhagic control.3
Supportive mathematical modelling has shown increased availability of all cell types in a single unit of WB than the sum of availability when given as individual blood components.4
Cost considerations for WB use require close collaboration with blood suppliers.
Possible risk of immunogenicity in emergency trauma situations; group O WB contains both anti-A and anti-B antibodies; so if used as a universal donor, testing is necessary to ensure the absence or low dose of anti-A or anti-B antibodies. A range of acceptable titers from 1:50 to 1:256 is described in the literature and will be related to the local donor community.5
Rh-negative WB should be reserved for females of reproductive age and other patients with known Rh-negative status.
Concerted and coordinated multi-disciplinary education must precede any planned WB use. At an institutional level, approval should be obtained from the chief medical officer and multi-disciplinary patient blood management committee. Physicians and nurses in the emergency medicine, surgical, anesthesiology and pathology departments as well as medical technicians require education. Initially, WB should be available on medevac helicopters (up to two units) and in trauma bays (up to four units) with a clearly distinctive label (Figure 1). Known contraindications should be publicized, accepting that these may not be identifiable in acutely injured patients, including known allo-antibodies, non-O blood groups, or patients with known malignancy or bone marrow transplantation requiring irradiated products.
Coordination With Local Blood Supplier
A WB program cannot be successful without support from blood suppliers. The Gulf Coast Regional Blood Center is providing group O blood from male-only donors with a 21-day expiration, no leukoreduction, and low anti-A and B titers (< 1:200). It is incumbent on the institution to facilitate management and stewardship of these valuable products to avoid unnecessary WB expiration and waste.
WB transfusion is under the review of the American Association of Blood Banks, or AABB, and the Food and Drug Administration. AABB approval is necessary for “variance use” (Standards for Blood Banks and Transfusion Services. 2015, AABB, Bethesda, MD, 30th edition), given current recommendation for ABO-group specific transfusion. Revisions to this AABB standard are forthcoming (31st edition, personal communication, Yu Bai, blood bank, Memorial Hermann Hospital, Texas Medical Center).