Enhanced oxygen availability and preserved aggregative function in platelet concentrates stored at reduced platelet concentration.

Background: Storage of platelets as platelet concentrates for transfusion is limited to 7 days in the United Kingdom due to deleterious effects on platelet quality and function that occur over time. Oxygen (O₂) availability and sufficient gaseous exchange are known to be essential in maintaining the viability and function of platelets stored for transfusion. Despite this, there is a paucity of studies undertaking direct measures of O₂ and optimization of conditions throughout storage. We address this and modulate the storage conditions to improve platelet quality and function.

Study design and methods: Electron paramagnetic resonance oximetry was implemented to directly measure the [O₂] experienced by stored platelet concentrates and the O₂ consumption rate under standard blood banking conditions. From these direct measures the mathematical modeling was then applied to predict the main parameters contributing to effective O₂ distribution throughout the unit.

Results: This study demonstrates reducing the storage [O₂] to reflect near physiological levels significantly alters O₂ distribution within the unit and negatively impacts platelet functionality and quality, and therefore is not a viable storage option.

Discussion: We show the reduction of platelet concentration within a unit improves O₂ availability and pH, promotes a more uniform distribution of O₂ throughout prolonged storage, and maintains platelet agonist-induced aggregation comparable to 100% platelet concentration. This may be a viable option and could potentially lead to reduced donor demand.