Blood supply resilience may be quietly transformed by a finding that challenges a half-century of platelet storage orthodoxy. The standard 5-to-7-day room-temperature shelf life for platelets creates chronic shortages, wastage, and logistical strain — particularly for complex cardiac procedures where platelet demand is high and unpredictable. A trial demonstrating viable cold storage beyond a week could meaningfully reshape transfusion medicine supply chains and patient outcomes.
The CHIPS trial — a phase 3, multicenter, adaptive noninferiority study conducted at 27 sites across the United States and Australia — enrolled pediatric and adult patients undergoing cardiac surgery with cardiopulmonary bypass between December 2021 and March 2025. Participants were randomized 2:1 to receive cold-stored platelets (CSPs, refrigerated at 1–6°C, maximum 21-day storage) versus conventional room-temperature platelets (RTPs, 20–24°C, maximum 7-day storage). The primary endpoint was a hemostatic efficacy score on a 1–5 scale, where higher scores indicated greater bleeding severity. The prespecified noninferiority margin was 1 point, and success required at least one cold-storage duration of 7 days or more to achieve a posterior probability of noninferiority of at least 97%.
This result carries considerable translational weight. Cold storage of platelets fell out of clinical favor in the 1970s after studies suggested refrigerated platelets had inferior post-transfusion survival in circulation — a concern later reframed by mechanistic work showing that cold-activated platelets may actually be more hemostatically potent precisely because of their activated state. The CHIPS trial's adaptive design, allowing duration-ranging up to 21 days, is methodologically sophisticated and positions these results for regulatory consideration. If confirmed in broader populations, cold storage could dramatically reduce platelet wastage rates — currently estimated at 10–20% of collected units in many health systems — and expand access in resource-limited or remote settings. Key caveats include the partially blinded design (full blinding of platelet temperature is logistically difficult), the specific cardiac surgery context limiting generalizability to other bleeding indications, and the need to assess platelet cold-storage outcomes beyond hemostatic scores to include thrombotic and immunologic endpoints over longer follow-up.