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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]

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. [ABSTRACT FROM AUTHOR]

Background and Objectives: The results of quality monitoring leucocyte counts were analysed nationally for the first 2 years of universal leucocyte depletion (LD), spanning the time-period before and after standardization of the counting and LD methods. The objectives were twofold: first to determine whether the implementation strategy was effective in achieving the LD specification (< 5 x 10(6) leucocytes in 99% of components with 95% statistical confidence); and second, whether quality monitoring was able to detect potential non-conformance., Materials and Methods: Residual leucocytes were counted using Beckman Coulter or Becton Dickinson (BD) flow cytometers and reagents. Data were collected into standardized analysis software (NWA Quality Analyst) for local trend analysis and checks for conformance to process specification, and collated centrally. Analysis was performed for six time-periods between January 1999 and March 2001. Specification failures were analysed to determine the likelihood of extreme failure. Statistical process monitoring was adjusted to suit LD processes., Results: Data from red cells in optimal additive solution (OAS), filtered either as whole blood or red cell concentrates, and platelet pools improved significantly over the 2-year period with specification failures falling from 0.35%, 0.48% and 0.56%, respectively, in January-June 1999 to 0.06%, 0.01% and 0.04% in January-March 2001. Specification failures in red cells in OAS LD for the period January-December 2000 showed only 0.02% with a leucocyte count of > 30 x 10(6)/unit. Extreme failures are now very rare. Monitoring methods have been effective in detecting process change and drift., Conclusion: LD performance varies between different LD systems, but monitoring has proved sufficiently robust to detect processes that perform poorly. The chosen specification has been both achievable and appropriate to the systems in use. Standardization of the counting method is central to the ability to monitor and analyse results effectively across the whole service.