Importance Patients undergoing cardiac surgery with cardiopulmonary bypass often require platelet transfusions for bleeding. Platelets are routinely stored at room temperature (20-24 °C) for up to 5 to 7 days; however, cold storage (1-6 °C) may allow for increased storage duration without loss of hemostatic function. Objective To determine the maximum cold-storage duration, up to 21 days, for which cold-stored platelets (CSPs) are noninferior or superior in hemostatic efficacy to room-temperature platelets (RTPs) when transfused in actively bleeding patients undergoing cardiac surgery with cardiopulmonary bypass. Design, Setting, and Participants A phase 3, multicenter, randomized, partially blinded, adaptive, noninferiority, storage duration–ranging trial conducted in pediatric and adult patients undergoing cardiac surgery with planned cardiopulmonary bypass at 27 sites in the US and Australia from December 2021 to March 2025. Statistical analysis was conducted from September 9 to October 3, 2025. Intervention Patients were randomized 2:1 to receive CSPs with a maximum of 21 days of storage vs RTPs with a maximum of 7 days of storage. Main Outcomes and Measures The primary outcome was a hemostatic efficacy score with values ranging from 1 to 5 and higher values indicating greater bleeding. The noninferiority margin was 1 point. The success criterion was met if at least 1 cold-storage duration of 7 days or more had a posterior probability of noninferiority of at least 97.5%. The secondary outcome was 24-hour chest tube output. Results Of the 1000 patients who underwent platelet transfusion, 989 were included in the primary analysis (650 CSPs and 339 RTPs). The cohort had a mean (SD) age of 42.1 (30.1) years and 67.8% were male. CSPs were noninferior to RTPs for the primary outcome, with a probability of greater than 99.9% for all cold-storage durations. Pooled across storage durations, CSPs had a mean difference from RTPs of 0.09 (95% credible interval, −0.06 to 0.23). Median (IQR) chest tube output at 24 hours (8.9 mL/kg [5.2-15.4] for CSPs vs 8.4 mL/kg [5.5-15.9] for RTPs; difference in medians, 0.4 [95% CI, −1.0 to 1.5]) was not statistically different between study groups. In a post hoc analysis, as all storage durations were noninferior, considering the CSPs as a single group, the hemostatic efficacy score was similar between both groups: mean (SD) of 3.08 (1.15) CSPs vs 2.99 (1.10) RTPs. There were no differences in venous or arterial thrombotic events, transfusion-associated adverse events, acute respiratory distress syndrome, kidney failure, septic shock, and mortality between the study groups, except for increased reexploration rates in the CSP group. Conclusions and Relevance For patients undergoing cardiac surgery, CSPs stored up to 21 days are noninferior to RTPs for the control of active surgical bleeding. Use of CSPs may allow for increased availability of platelets by reducing wastage and shortages and may allow for incorporation of platelets into inventory at locations where platelets cannot be maintained due to the 5- to 7-day shelf life of RTPs. Trial Registration ClinicalTrials.gov Identifier: NCT04834414
Expanding the platelet inventory to mitigate the impact of severe shortages
Abstract The platelet collection and distribution system, based on volunteer nonremunerated donors, apheresis platelet collections, and primarily 1-directional distribution of platelets for up to 5-day room temperature storage at hospitals, typically performs well and provides therapeutic support for hundreds of thousands of patients annually. However, direct and indirect effects of the coronavirus disease 2019 pandemic, particularly during the Omicron wave, produced dramatic systemic failures and severe shortages. We propose 4 initiatives to reinforce the existing platelet pipeline and buffer the platelet supply against future unexpected disruptions.
Clinical Practice Guidelines From the Association for the Advancement of Blood and Biotherapies (AABB): COVID-19 Convalescent Plasma
Seasonal variability is not observed in the rates of high anti‐A and anti‐B titers in plasma, apheresis platelet, and whole blood units tested by different methods
BACKGROUNDABO‐incompatible platelet transfusions are common, and transfusions with ABO‐incompatible plasma are increasing with the use of group A plasma and group O whole blood (WB) in emergencies. Many centers screen blood products for anti‐A and/or anti‐B titers to help prevent hemolysis from ABO‐incompatible transfusions, yet titer methods and definition of high titers are not standardized.STUDY DESIGN AND METHODSThis international multicenter study collected data on anti‐A and anti‐B titer practices for plasma, apheresis platelet (AP), and WB units from January 2015 through December 2017 to determine the prevalence of high‐titer units using local definitions.RESULTSA total of 87,701 plasma, AP and WB units were screened for high‐titer anti‐A and/or anti‐B. High‐titer detection rates for group A plasma ranged 0%–13.6%; group A AP 2.7%–9.3%; group O AP 2.3%–65.7%; and group O WB 6.4%–20.7%. At the one center that collected group B AP, the high‐titer rate was 10.9%. High‐titer rates varied from month to month, as well as between years for a given month. There was no clear pattern of when high‐titer units were donated.CONCLUSIONThe prevalence of high‐titer plasma, AP, and WB units varies by titer method and local definition of high titer. Even at the lowest titer threshold of 50, a significant proportion of units had a high‐titer antibody, although the clinical relevance of this finding needs further investigation.
2015 proceedings of the National Heart, Lung, and Blood Institute's State of the Science in Transfusion Medicine symposium
On March 25 and 26, 2015, the National Heart, Lung, and Blood Institute sponsored a meeting on the State of the Science in Transfusion Medicine on the National Institutes of Health (NIH) campus in Bethesda, Maryland, which was attended by a diverse group of 330 registrants. The meeting's goal was to identify important research questions that could be answered in the next 5 to 10 years and which would have the potential to transform the clinical practice of transfusion medicine. These questions could be addressed by basic, translational, and/or clinical research studies and were focused on four areas: the three “classical” transfusion products (i.e., red blood cells, platelets, and plasma) and blood donor issues. Before the meeting, four working groups, one for each area, prepared five major questions for discussion along with a list of five to 10 additional questions for consideration. At the meeting itself, all of these questions, and others, were discussed in keynote lectures, small‐group breakout sessions, and large‐group sessions with open discourse involving all meeting attendees. In addition to the final lists of questions, provided herein, the meeting attendees identified multiple overarching, cross‐cutting themes that addressed issues common to all four areas; the latter are also provided. It is anticipated that addressing these scientific priorities, with careful attention to the overarching themes, will inform funding priorities developed by the NIH and provide a solid research platform for transforming the future practice of transfusion medicine.
A comparison of adverse reaction rates for PAS C versus plasma platelet units
BackgroundPlasma constituents have been implicated in some types of platelet (PLT) transfusion reactions. Leukoreduced apheresis PLTs stored in InterSol have 65% less plasma than apheresis PLTs stored in 100% plasma (PPs). This study compared transfusion reaction rates in InterSol PLTs (PLT additive solution [PAS] C) versus PPs.Study Design and MethodsThe study design was an open‐label, nonrandomized retrospective review. Statistical methods were applied to substantiate noninferiority and superiority of PAS C compared to PP in terms of transfusion reaction rates. Adverse reactions (ARs) were categorized using the Biovigilance Component of the National Healthcare Safety Network. Active surveillance was used to monitor all transfusions, both with ARs and without ARs.ResultsA total of 14,005 transfusions from six study sites were included, with 9845 PP transfusions given to 2202 patients and 4160 PAS C to 1444 patients. A total of 165 ARs were reported. Percentages of transfusions with ARs were 1.37% for PPs, 0.55% for PAS C, and 1.13% overall. The relative risk (RR) for PAS C versus PPs was calculated as 0.403 with an upper confidence limit (UCL) of 0.663. Overall, ARs with the highest incidence were allergic transfusion reactions (ATRs) and febrile nonhemolytic transfusion reactions (FNHTRs), at 0.66 and 0.40% of total transfusions reported, respectively. The relative risks (UCLs) for ATRs and FNHTRs, respectively, were 0.350 (0.686) and 0.336 (0.827).ConclusionsPAS C PLTs were statistically superior and noninferior to PPs with respect to the transfusion‐related AR rate. PAS C noninferiority and superiority were also demonstrated for ATRs and FNHTRs, separately.
How we developed and use the
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pheresis guidelines for therapeutic apheresis pro
The decision to treat a patient with therapeutic apheresis depends on multiple factors, such as what does the patient most likely have, is the diagnosis amenable to apheresis treatment, what is the harm‐versus‐benefit ratio of apheresis treatment in this patient, and what are the internal and external issues associated with receiving apheresis treatment? The “ G uidelines on the U se of T herapeutic A pheresis in C linical P ractice— E vidence‐based A pproach from the Writing C ommittee of the A merican S ociety for A pheresis” addresses these issues and helps aid in clinical decision making. The development and application of these G uidelines as well as potential new applications will be discussed in this article.
Guidelines on the Use of Therapeutic Apheresis in Clinical Practice—Evidence‐Based Approach from the Writing Committee of the American Society for Apheresis: The Sixth Special Issue