Delayed Cold-Stored Platelets -PLTS-1

To prepare cold-stored platelets, blood banks will transition conventional room temperature platelets up to 4 days after collection (with agitation) to cold-storage (at 1-6 C without agitation) for a minimum of 1 day (24 hours) and a maximum of 10 days after collection (for a total shelf life of ≤ 14 days after collection). Thus, cold-stored platelets will be produced and stored the same way as room temperature platelets up until their transition to cold-storage, ensuring similar products differing only in storage conditions and expiration date (as cold-stored platelets will have an expiration date beyond the current 5 days for pathogen inactivated platelets or 7 days for bacterially cultured platelets). Pathogen reduced platelets will be used for the pilot study (Canada is transitioning in 2022-23 to pathogen-reduced platelets and one site has already transitioned).

Room temperature stored platelets are prepared from donor whole blood, which is centrifuged to collect the buffy coat layer containing platelets. Seven ABO matched buffy coats from male and/or female donors are pooled in 280 ml of platelet additive solution and split into a single dose after pathogen inactivation, resulting in a product with a final platelet count of approximately 1300 x 109. Pathogen inactivated platelets (shelf-life of 5 days, with recent Health Canada approval for an extension of the shelf-life to 7 days), will be used as Canada is transitioning in 2022-23 to pathogen-inactivated platelets and one site has already transitioned.