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Background: As patient blood management becomes more widespread, fewer red blood cell (RBC) units have been transfused. This multinational study evaluated changes in blood center RBC distributions., Study Design and Methods: Data on number and ABO and D groups of RBC distributions were obtained from several large American blood centers and national or provincial blood services (NPBS) from fiscal year (FY) 2010 through FY2014. Due to relatively larger numbers of distributions and differences in ABO and D groups between the Japanese Red Cross and the other NPBS, Japanese data were not included in distributions calculations., Results: Data from seven American blood centers and eight NPBS were obtained. Overall, at both the American and the seven NPBS that were analyzed, there were declines in the number of RBC distributions between FY2010 and FY2014, 16.9 and 8.0%, respectively. The number of O- RBC distributions decreased by 9.0% at American blood centers but the proportion of RBC distributions that were O- increased by 9.3% during this time. The NPBS had 1.6% increase in O- RBC distributions and 10.5% increase in the proportion of O- distributions. The proportion of O+ distributions increased slightly over time at American centers (2.9%) while decreasing slightly (1.1%) at NPBS despite reductions in the absolute numbers of O+ distributions. Overall there was 2.6% decrease in the proportion of B+ and AB+ RBCs distributed and 13.6% absolute reduction in the number of these units distributed., Conclusion: Although overall RBC distributions have decreased over time, the proportion of O units has increased substantially., (© 2016 AABB.)

Background: Clinical trials are investigating the potential benefit resulting from a reduced maximum storage interval for red blood cells (RBCs). The key drivers that determine RBC age at the time of issue vary among individual hospitals. Although progressive reduction in the maximum storage period of RBCs would be expected to result in smaller hospital inventories and reduced blood availability, the magnitude of the effect is unknown., Study Design and Methods: Data on current hospital blood inventories were collected from 11 hospitals and three blood centers in five nations. A general predictive model for the age of RBCs at the time of issue was developed based on considerations of demand for RBCs in the hospital., Results: Age of RBCs at issue is sensitive to the following factors: ABO group, storage age at the time of receipt by the hospital, the restock interval, inventory reserve, mean demand, and variation in demand., Conclusions: A simple model, based on hospital demand, may serve as the basis for examining factors affecting the storage age of RBCs in hospital inventories. The model suggests that the age of RBCs at the time of their issue to the patient depends on factors external to the hospital transfusion service. Any substantial change in the expiration date of stored RBCs will need to address the broad variation in demand for RBCs while attempting to balance considerations of availability and blood wastage., (© 2013 American Association of Blood Banks.)

Background: Oxidative stress is a major driving force in the development of storage lesions in red cell concentrates (RCCs). Unlike manufactured pharmaceuticals, differences in component preparation methods and genetic/physiological status of donors result in nonuniform biochemical characteristics of RCCs. Various characteristics of donated blood on oxygen saturation (SO2) distribution were investigated, and a model to estimate potential oxidative stress burden of stored RCC at transfusion is proposed. Study design and methods: The oxygen content of freshly prepared RCCs (770) was quantified noninvasively as fractional hemoglobin saturation (SO2) with visible reflectance spectrometry. Using separate RCCs and mimicking typical handling of RCCs during routine storage, evolution of SO2 was followed for construction of an empirical model. Based on this model, the oxygen exposure index (OEI) was formulated to estimate the accumulated oxygen exposure burden of RCC at the time of transfusion. Results: The SO2 of RCCs varied widely at donation (mean 43% ± 1.3%; range 20%–93%). Multivariate regression model showed that sex and processing method had small effects on SO2 (R2 = 0.12), indicating that variability was mainly attributed to other individual donor characteristics. Storage simulation model indicated that median SO2 increased gradually over 6 weeks (approx. 1.3 fold), while OEI increased at a faster rate (approx. eight‐fold). Conclusion: In addition to storage age, the OEI provides a potential new metric to assess the quality of RCCs at the time of transfusion in terms of their oxidative stress. In future studies, a single noninvasive measurement during storage could link OEI to clinical outcomes in transfusion recipients. [ABSTRACT FROM AUTHOR]