The oxygen saturation of red blood cell concentrates: The basis for a novel index of red cell oxidative stress

Abstract

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.

A deep 96-well plate RBC storage platform for high-throughput screening of novel storage solutions

“…Table 1A shows the ATP values for the N and for H RBCs throughout the 6-week storage accompanied by descriptive statistics and the results of analysis by a mixed model analysis of variance ( Table 3 ). Higher ATP levels were observed for samples stored hypoxically, as reported previously ( Yoshida and Shevkoplyas, 2010 ; Dumont et al, 2016 ; Yoshida et al, 2022 ) with an overall estimated difference = 0.48µmol/gHb, p ≤ 0.0001. The three observed ATP profiles of the samples stored in the 96-well plate with PVC strips were similar to the values and trends seen in samples stored in PVC bags, both in N and H storage conditions over the 6-week study period.…”

“…A large and expected difference in the sO 2 was maintained between N and H samples throughout the study (Figure 2A) as intended. Under N conditions a noticeable difference of sO 2 was observed between the bag and the plate samples Frontiers in Physiology frontiersin.org (Figure 2A), which can be attributed to the bag having a larger surface area exposed to ambient air and allowing for higher levels of oxygenation due to O 2 diffusion during storage (Yoshida et al, 2022). Additionally, metallic foil seals were used for both types of plates, which eliminated O 2 ingress from the top.…”

Evaluating the effects of hypoxic storage on platelet function and health using a novel storage system

“…Figure 1 provides an illustration of the processing method. Briefly, HbSO 2 was measured non-invasively using a moorVMS-OXY Tissue Oxygen Monitor (Moor Instruments Inc., Wilmington, DE), a device designed to measure shallow tissue oxygenation levels based on visible reflectance spectroscopy, 23 and recorded before transferring approximately 100 mL into a 150 mL Fenwal transfer pack container (Fresenius Kabi, Bad Homburg, Germany), which served as the normoxic control. The remaining WB was transferred to the Hemanext ONE ® System's ORB and placed in a blood bank agitator (Helmer, Noblesville, IN) at room temperature, with periodic assessment of HbSO 2 .…”

Effect of Hypoxic Blood Infusion on Pulmonary Physiology

“…Typically, RBC units prepared from donors are characterized by fractional O 2 saturation of hemoglobin (SO 2 ) ranging from 30-68% (49 ± 19) with corresponding PO 2 of about 70 mmHg (Dumont et al, 2016;Yoshida et al, 2021). Leukocytes and plasma usually are removed before RBC storage under refrigerated conditions (≈2-6 • C).…”

“…When RBCs are separated from plasma, the packed RBCs are stored in a solution formulated to achieve post-transfusion survival of at least 75% in healthy autologous donors, with less than 1% pre-transfusion hemolysis while maintaining adequate levels of adenosine triphosphate (ATP). The storage bag is made of an oxygen-permeable Polyvinyl Chloride (PVC) film and placed in room air (PO 2 ≈155 mmHg; PCO 2 ≈0 mmHg), gradually gaining oxygen during storage estimated to reach SO 2 of 59-94% at day 42 (Yoshida et al, 2021).…”