Seven‐day storage of random donor PLT concentrates

BACKGROUND:  PLT concentrates are licensed for use up to a maximum of 5 days of storage. Increasing storage to 7 days would improve the logistics of supply and have the potential to reduce wastage. STUDY DESIGN AND METHODS:  PLTs were prepared from CP2D blood with standard procedures (n = 16) and then WBC‐reduced. Sampling was carried out at 3, 5, and 7 days for PLT count, pH, aggregation to ADP and collagen, hypotonic shock response, Kunicki morphology score, thromboelastogram response, pO 2 , and pCO 2 , and PLT activation (CD62) was carried out by flow cytometry. Additionally, PLTs stored for 7 days were transfused into thrombocytopenic patients, and the CCI was calculated. RESULTS:  Some of the in vitro tests such as the aggregation response to single stimuli showed decreased values with time. The hypotonic shock was well maintained for 7 days (77%‐68%); the Kunicki morphology score showed progressive shape change (300 to 164). The CCI of 7‐day PLTs averaged 16,000 (n = 9). CONCLUSIONS:  The data indicate acceptable in vitro PLT function at 7 days. Transfusion of the 7‐day‐old CP2D PLTs resulted in an appropriate posttransfusion increment in thrombocytopenic patients. Random donor PLTs collected into CP2D can be successfully stored for 7 days before use.