Transfusion of stored platelets: balancing risks and product availability

Cécile Aubron,1,2 Andrew W Flint,2,3 Yves Ozier,4 Zoe McQuilten2,5 1Medical Intensive Care Unit, Centre Hospitalier et Universitaire de Brest site La Cavale Blanche–Université de Bretagne Occidentale, Brest, France; 2Department of Epidemiology and Preventive Medicine, The Australian and New Zealand Intensive Care Research Centre, Monash University, Melbourne, VIC, Australia; 3Royal Australian Navy, Australian Defence Force, Canberra, ACT, Australia; 4Department of Anesthesiology, Centre Hospitalier et Universitaire de Brest site La Cavale Blanche–Université de Bretagne Occidentale, Brest, France; 5Department of Epidemiology and Preventive Medicine, Transfusion Research Unit, Monash University, Melbourne, VIC, Australia Abstract: Platelet (PLT) transfusions are used for both treatment of bleeding and preventing bleeding in patients with thrombocytopenia and/or functionally abnormal PLTs. To ensure the efficacy of transfused PLTs, they must be stored at room temperature. Due to this storage requirement, PLTs have a short shelf life compared with other blood components of up to 5–7 days to minimize the risk of bacterial contamination. This short shelf life can lead to PLT shortages at times of increased demand or reduced supply and also higher wastage due to expiry. Increasing the PLT storage duration has the potential to improve PLT availability at times of altered demand or supply. However, in addition to the risk of bacterial contamination, functional and biochemical changes occur in PLTs and their storage medium during storage that may lead to PLT activation, changes in efficacy, and adverse events. This narrative review analyzes the issues around PLT inventory management and potential risks of stored PLTs. Although in vitro studies show accumulation of reactive biomarkers in PLT units, the clinical significance of these changes remains uncertain and there is currently no evidence for an association between PLT storage duration and adverse events. Furthermore, PLTs processed and stored for up to 7 days in defined conditions could be as safe as fresh PLTs. Large prospective studies are warranted to better evaluate the safety of PLTs with extended storage and to define the best practice of optimizing PLT inventory management while maintaining PLT transfusion safety. Keywords: platelet storage, storage lesion, PLT inventory management, transfusion adverse events