Preparing small-dose red cell concentrates (RCCs) for neonatal and pediatric transfusions: Impact of RCC volume, storage, and irradiation.

BACKGROUND: Preparing small-dose red cell concentrates (RCCs) is a common practice for pediatric and neonatal transfusions. However, there is a lack of quality monitoring data to indicate that both the preparation and storage of small-dose RCCs does not alter in vitro red cell quality. The present study seeks to provide data to support this practice. MATERIALS AND METHODS: To evaluate quality of stored small aliquots, six ABO/Rh matched leukoreduced citrate phosphate-dextrose/saline-adenine-glucose-mannitol (LR CPD/SAGM) RCCs were pooled and split into 30 ml aliquots, 80 ml aliquots, and a standard 290 ml unit, with testing performed for up to 43 days post-collection. To evaluate the impact of irradiation on small-dose RCC preparation, a total of 48 independent LR CPD/SAGM RCCs were used (non-irradiated: n = 24; irradiated: n = 24). Aliquoting with/without irradiation was performed within 7 days of collection and baseline testing was performed within 24 h of aliquot production. RESULTS: Limited variability in hemolysis, mean cell volume, and extracellular potassium concentrations were seen between the different aliquot sizes throughout the 43-day storage period. Aliquot production did not accentuate damage based on any of these tested parameters in both the non-irradiated and irradiated subsets. A significant increase was seen in the potassium concentrations in the irradiated parent and aliquot samples relative to their non-irradiated counterparts. CONCLUSIONS: Non-irradiated small-aliquot dose RCCs meet in vitro quality criteria required for safe transfusion throughout the 42-day storage period. The same can be said for aliquots derived from irradiated units and tested within 24 h of aliquot production.

Minimal impact of anticoagulant on in vitro whole blood quality throughout a 35-day cold-storage regardless of leukoreduction timing.

BACKGROUND: There is increasing interest in leukoreduced whole blood (WB) as a transfusion product for trauma patients. In some jurisdictions, few leukoreduced filters are approved or appropriate for WB leukoreduction and quality information is therefore limited. This study assessed the impact of filtration timing of WB collected in CPDA-1 versus CPD on in vitro quality. STUDY DESIGN AND METHODS: WB was collected in CPDA-1 or CPD and leukoreduction filtered either after 3-8 h (early) or 18-24 h (late) from stop bleed time. In vitro quality was assessed after filtration and throughout 5 weeks of storage at 4°C. Cell count and hemoglobin levels were determined by hematology analyzer, platelet activation and responsiveness to ADP by surface expression of P-selectin by flow cytometry, hemolysis by HemoCue, and metabolic parameters by blood gas analyzer. Hemostatic properties were assessed by rotational thromboelastometry. Plasma protein activities and clotting times were determined by automated coagulation. RESULTS: Although there were some data points which showed statistically significant differences associated with anticoagulant choices or the filtration timing, no general trend in inferiority/performance could be discerned. After 35 days' storage, only clotting time, alpha angle and factor II in the early filtration arm comparing anticoagulants and prothrombin time and factor II in the CPDA-1 study arm comparing filtration timing showed a significant difference. CONCLUSION: In vitro WB quality seems to be independent on the choice of anticoagulant and filtration timing supporting WB hold-times to up to 24 h, increasing operational flexibility for transfusion services.

Assessment of bacterial growth in leukoreduced cold-stored whole blood supports overnight hold at room temperature prior to filtration: A pilot study.

BACKGROUND AND OBJECTIVES: Whole blood (WB) transfusion has regained attention to treat trauma patients. We reported no significant changes in in vitro quality through 21 days of cold storage for leukoreduced WB (LCWB) when time to filtration was extended from 8 to 24 h from collection. This study evaluated the impact of extended WB-hold at room temperature (RT) prior to leukoreduction on proliferation of transfusion-relevant bacteria. MATERIALS AND METHODS: WB units were spiked with suspensions of Klebsiella pneumoniae, Streptococcus pyogenes, Staphylococcus aureus and Listeria monocytogenes prepared in saline solution (SS) or trypticase soy broth (TSB) to a concentration of ~0.2 CFU/ml (N = 6). Spiked units were held at RT for 18-24 h before leukoreduction and cold-stored for 21 days. Bacterial growth was determined on days 2, 7, 14 and 21. In vitro quality of WB inoculated with unspiked diluents was assessed. RESULTS: K. pneumoniae and S. pyogenes proliferated in WB prior to leukoreduction reaching concentrations ≤102 CFU/ml. These bacteria, however, did not proliferate during the subsequent cold storage. S. aureus did not survive in WB while L. monocytogenes reached a concentration of ~102 CFU/ml by day 21. LCWB in vitro quality was not affected by SS or TSB. CONCLUSION: Extended WB-hold prior to leukoreduction allowed proliferation of bacteria able to resist immune clearance, although they did not grow to clinically significant levels. While L. monocytogenes proliferated in LCWB, clinically relevant concentrations were not reached by day 21. These data suggest that transfusing LCWB may not pose a significant bacterial contamination safety risk to transfusion patients.

Estimating the impact on the inventory of implementing pathogen-reduced platelets in Canada.

BACKGROUND: Pathogen reduction (PR) technology will be implemented in pooled platelets in Canada. It is anticipated that PR platelets will be licensed in Canada for a maximum shelf life of 5 days, while non-treated apheresis platelet products will continue to be licensed for 7 days. STUDY DESIGN AND METHODS: This study evaluates the impact on inventory, wastage, and shortages of implementing PR platelets. A custom-built simulation model was used to represent a regional distribution network. Experiments with the model were used to estimate product wastage and shortages when a 5-day PR pooled platelet product is introduced alongside a 7-day apheresis platelet product. RESULTS: Pooled platelet waste and shortages both increase as pooled shelf life decreases. Apheresis platelets, however, show a different response: While shortages of apheresis platelets increase as the shelf life of pooled units decreases, apheresis waste declines as pooled shelf life decreases. CONCLUSION: Additional platelet collections will be necessary to accommodate the shorter PR platelet shelf life and to cover increased patient transfusion needs due to a lower platelet yield in PR units. Increases of 9% for pooled units and 6% for apheresis units beyond expected demand, were found to be sufficient to ensure a non-inferior level of customer service while minimizing waste.

Cold-stored leukoreduced whole blood: Extending the time between donation and filtration has minimal impact on in vitro quality.

BACKGROUND: Leukoreduced whole blood (LR-WB) has received renewed attention as alternative to component-based transfusion in trauma. According to the manufacturer's instructions, leukoreduction should be carried out within 8 h after collection. This study assessed impact of (1) WB collection bag, (2) LR filtration, and (3) timing of filtration on in vitro quality. STUDY DESIGN AND METHODS: WB collected into different vendor bags was held at room temperature for <8 h or >16 h but <24 h prior to LR. In vitro quality was assessed before and after filtration, and throughout 3 weeks of storage at 4°C. Cell count and hemoglobin levels were determined by hematology analyzer, platelet activation, and responsiveness to ADP by surface expression of P-selectin by flow cytometry, hemolysis by HemoCue, and metabolic parameters by blood gas analyzer. Hemostatic properties were assessed by rotational thromboelastometry. Plasma protein activities and clotting times were determined by automated coagulation analyzer or quantitative immunoblotting. RESULTS: Bag type had no impact on WB in vitro quality. LR by filtration had some impact, but is aligned with data in the literature. The time between donation and filtration resulted in some statistically significant differences in metabolic activity, platelet yield, platelet activation, and factor protein activity initially; however, these differences in in vitro quality attributes decreased throughout 21-day cold storage. CONCLUSION: WB hold time showed only a minor impact on WB in vitro quality, so it may be possible for blood processing facilities to explore extended hold times prior to filtration in order to provide greater operational flexibility.