Disproportionate outdating of group A blood

The authors studied the factors responsible for the disproportionate outdating of group A blood compared with group O blood over a 6-month interval. Distribution, transfusion, and outdate data for 99,251 units of blood were collected from representative hospitals within the region served by the Atlanta Regional Red Cross Blood Center. Factors evaluated included: neonatal transfusion of type O blood to type A recipients; use of type O blood in emergencies or due to group-specific shortages; demographic donor and recipient differences; and blood importing practices. Of 43,757 group O units (44.1% of total) available for distribution, 2050 (4.7%) were outdated, compared with 3908 (10.7%) of 36,501 group A units (36.8% of total). One thousand two hundred and seventy-nine units of type O blood were transfused to recipients who were not type O, including 842 group A neonatal patients. A larger inner-city hospital, where 46.8 percent of recipients were group O and 29.2 percent were group A, accounted for 180 more group O and 509 fewer group A transfusions than would be expected if donor-recipient ABO distributions were the same. Three hundred and seventy-four more group A units were imported than were needed. ABO-mismatched transfusions due to shortage or emergency were insignificant. It was concluded that increased use of group O blood for neonatal transfusions, donor-recipient differences in blood group frequencies, and blood importing practices are the major factors that increase the rate of group A outdating.