Cold and Room-Temperature Platelets in Cardiac Surgery
Philip C. Spinella, Nicole D. Zantek, John M. VanBuren, Susan C. Nicolson, Ashish K. Khanna, Allan M. Klompas, Michael L. Boisen, Tiffany M. Williams, Matthew Monteleone, Dalia A. Bashir, Warren Pavey, Bradford B. Smith, M. Iqbal Ahmed, Robert A. Niebler, Eric Jeng, Brigid C. Flynn, Ravi V. Joshi, James F. Preuss, Dheeraj Goswami, Chisa Yamada, Choy Lewis, Claudia S. Cohn, Hlaing Tint, Jenny Kwak, Neel Sodha, Eric R. Simon, Philbert Y. Van, Philip E. Greilich, Frank V. McL. Booth, Camille P. Carter, Anastazia Keegan, Andrew P. Cap, James Matuk, Anna McGlothlin, Nicholas S. Berry, Roger J. Lewis, Marie E. Steiner, , Paula Hu, Jaleah Hawkins, David R. Jobes, Emmanuel A. Fadeyi, Abigail M.A. Reynolds, Carter G. Bell, Mark M. Smith, Manish J. Gandhi, Beth Montonye, Alesia Kaplan, Derek Serna-Gallegos, Ibrahim Sultan, Stephanie Kinney, Kathleen Molony, Lisa Hensch, Ashraf Resheidat, Martine Malivers, Rebbecca Hahn, Annette Le Viellez, Dominic Pepperell, Qun Lu, Frank X. Downey, Kayla N. Haeger, Sirine A. Baltagi, Robert D.B. Jaquiss, Daniel K. Noland, Regina Cole, Aspen Duffin, John P. Scott, Long Zeng, Angie Ballew, Christopher Webb, Michael Jessen, Erryn Hopson, Peri Mickle, Simon Kavanagh, Shannon Matzelle, Liz Crowe, Colleen Mennie, Robertson Davenport, Therese Chlebeck, Emmy Zenk, Daniel T. Lotz, Warren Choi, Rhonda Hobbs, Amanda Baptise, Phillip DeChristopher, Nancy Schoenecker, Dianna Rodheim, Joseph Connor, Daniel J. Griese, Erin McGuire, Mandy VanSandt, Valerie Sera, Justine O’Donovan, Denese Marks, Lacey Johnson, Kert Viele, Jill M. Cholette, Jerrold H. Levy, Frank Selke, Toby Silverman, Susan Shea, Mark Yazer, Pampee Young, Paul Ness, Geir Strandenes, J. Michael Dean, Beth Shaz, James StubbsImportance
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: