BACKGROUND: Advantages to storing whole blood–derived platelets (PLTs) as a pool for 7 days would include operational efficiencies and facilitation of bacterial testing and pathogen inactivation. The in vitro quality of pre‐storage pooled PLTs stored for up to 7 days was assessed.
STUDY DESIGN AND METHODS: Leukoreduced PLTs were pooled before storage (5 units/pool) and stored for either 5 or 7 days. Samples were collected at the time of pooling and either on Day 5 (n = 16‐29) or on Day 7 (n = 4‐30) and tested for biochemical and activation markers and morphology and/or shape change. Control PLTs were stored individually for 5 or 7 days and then tested as indicated above.
RESULTS: The mean PLT counts (×109/L) were similar: control PLTs, 1344 (464 SD); and prestorage pooled PLTs, 1327 (220 SD; p = 0.93). On Day 5, the pH value was significantly lower (p ≤ 0.0001) for the prestorage pooled PLTs. Lactate and partial pressure of O2 (pO2) were significantly higher (p ≤ 0.003). On Day 7 of storage, significant differences were noted with pH, pCO2, and hypotonic shock all being lower with the prestorage pooled product, whereas pO2, lactate, and morphology scores were higher (p values all < 0.03). Although significant differences were found, the magnitude of the difference would not be expected to impact on transfusion outcomes.
CONCLUSION: These results suggest that prestorage pooled PLTs can be stored for up to 7 days; however, studies are needed to ensure that the clinical benefit of PLTs stored as a pool is not inferior to those stored individually.