Cold-Stored Platelets Could Transform Blood Supply And Help More Patients

A simple change in how platelets are stored could mean fewer shortages, less wastage, and potentially greater access to lifesaving transfusions.

Highlights:

• Cold-stored platelets kept for up to 21 days controlled active bleeding during cardiac surgery as effectively as conventional room-temperature platelets




• Longer platelet storage could reduce wastage and improve availability, especially for hospitals facing unpredictable demand or limited blood inventories




• The findings are promising but currently apply most directly to actively bleeding cardiac surgery patients studied in the CHIPS trial

Imagine a blood component that can help stop dangerous bleeding but has to be used within just a few days. That narrow window makes every platelet donation a race against time. Platelets are routinely stored at room temperature for only five to seven days, creating challenges for hospitals managing unpredictable demand.

Now, researchers have tested an unexpectedly simple solution: keeping donated platelets refrigerated instead. A major randomized clinical trial found that chilled platelets stored for up to 21 days controlled active bleeding during cardiac surgery as effectively as standard room-temperature platelets (1). The finding could potentially change how hospitals think about platelet shortages, wastage, and access to transfusions.

Can Platelets be Stored in the Refrigerator for 21 Days?

The short answer is yes, at least for the specific clinical situation studied. The CHIPS randomized clinical trial compared cold-stored platelets kept at 1 to 6°C with conventional platelets stored at 20 to 24°C. Standard platelets can generally be stored for five to seven days, whereas the study tested refrigerated platelets for periods extending to 21 days. The refrigerated platelets remained noninferior for controlling active surgical bleeding in patients undergoing cardiac surgery.

That distinction matters because platelets are not simply another component of donated blood. They are living cell fragments that participate directly in forming clots and stopping bleeding. Their short storage life creates logistical difficulties, particularly when demand suddenly rises, or hospitals are located far from major blood centres. Extending storage could therefore give blood banks considerably more flexibility when managing their inventories.

What did the New Chilled Platelet Study Find?

The phase 3 CHIPS trial included adults and children undergoing cardiac surgery with cardiopulmonary bypass across 27 centres in the United States and Australia. Among 1,000 participants who received study platelets, 650 received cold-stored units while 339 received room-temperature units in the primary analysis. Researchers assessed how effectively transfused platelets helped control bleeding following surgery. Cold-stored platelets had a greater than 99.9% probability of being noninferior to conventional platelets across the tested storage durations.

The numbers were remarkably close when researchers compared the main bleeding-control measure between groups. The mean hemostatic efficacy score was 3.08 with cold-stored platelets compared with 2.99 for room-temperature platelets. 24-hour chest tube drainage also showed no statistically meaningful difference between the groups. Major outcomes including mortality, thrombotic events, kidney failure, septic shock, and transfusion-related adverse events were not significantly different, although reexploration rates were higher in the cold-storage group.

Why is Cold Platelet Storage such a Big Deal?

The importance of this discovery becomes clearer when you look at what happens before a platelet reaches a patient. Platelet donations require careful collection, testing, and controlled storage, followed by continuous agitation under carefully maintained conditions. Because their conventional shelf life is so short, some donated units can expire before the right patient needs them. The usable window can become even shorter because testing consumes part of those precious days.

Refrigeration could change that equation by dramatically extending the inventory window. A 21-day storage period would be roughly three times longer than the conventional maximum of seven days. That extra time could reduce wastage and make it easier for hospitals to maintain supplies during periods of unpredictable demand. Researchers also suggest that cold storage could potentially make platelet inventories feasible in locations that struggle to maintain conventional room-temperature supplies.

Do Cold-Stored Platelets Work as Well as Fresh Platelets?

The study provides reassuring evidence for bleeding control, but it does not suggest that every platelet transfusion should immediately switch to refrigerated products. The trial specifically examined patients actively bleeding during cardiac surgery involving cardiopulmonary bypass. Researchers found similar clinical hemostatic outcomes despite known differences in how cold-stored platelets behave after transfusion.

Cold storage can make platelets more immediately active while reducing how long they remain circulating after transfusion. This means platelet counts after transfusion may not rise in exactly the same way as they do with room-temperature products. Clinical effectiveness, rather than platelet count alone, was therefore crucial to interpreting this trial. Further research and regulatory decisions will determine where cold-stored platelets should become part of routine practice.

Future Of Blood Transfusions

For someone needing an urgent platelet transfusion, the biggest benefit could be something remarkably simple: availability. More flexible storage could mean blood banks have a better chance of having compatible platelets available when serious bleeding occurs. This could be particularly valuable during emergencies, major operations, disasters, or situations where transportation from larger blood centres takes time. A longer shelf life could make lifesaving platelets easier to keep within reach.

The findings should still be viewed as an important step rather than an immediate worldwide change in transfusion practice. The trial focused on cardiac surgery, so researchers need to establish how well these findings translate to trauma, obstetric bleeding, cancer care, and other situations requiring platelet transfusion. For now, the message is encouraging: something as ordinary as refrigeration may help solve an unusually difficult problem in modern blood medicine.

Frequently Asked Questions

Can platelets be stored in a refrigerator?
Yes, the CHIPS trial found that platelets stored at 1 to 6°C for up to 21 days remained effective for controlling active bleeding during cardiac surgery.

How long are platelets normally stored?

Conventional platelets are generally stored at room temperature for approximately five to seven days.

Are cold-stored platelets safe?

The trial found no significant differences in most major safety outcomes between cold-stored and room-temperature platelets.

Why do platelets have such a short shelf life?

Room-temperature storage limits platelet shelf life because of bacterial contamination risks and progressive changes affecting platelet quality.

Will all hospitals start using chilled platelets now?

Not immediately, because further evidence and regulatory decisions are needed before wider routine use can be established.

References:

1. Cold and Room-Temperature Platelets in Cardiac Surgery: The CHIPS Randomized Clinical Trial
   
   (Spinella PC, Zantek ND, VanBuren JM, et al. Cold and Room-Temperature Platelets in Cardiac Surgery: The CHIPS Randomized Clinical Trial. JAMA. Published online August 17, 2026. doi:10.1001/jama.2026.13328)

Source-Medindia