Platelet function after storage in leukocyte : reduced whole blood and preheating to 37°C

Abstract: Introduction: Whole blood transfusions are indicated for the resuscitation of patients with hemorrhagic trauma. In Sweden, whole blood is stored for 14 days at 4°C. If possible, refrigerated blood is rewarmed to 37°C before transfusion to avoid hypothermia. Platelets contribute to hemostasis and can be activated with several pathways. During storage, shedding of platelet surface receptors takes place. Further research on how platelet storage in whole blood and rewarming before transfusion affect platelets is needed. Aim: The aim was to study how storage in whole blood and rewarming to 37°C affect platelet function, platelet activatability, and changes in platelet surface receptors. Method: Whole blood from two healthy donors was stored for 14 days. During these 14 days, two blood samples were taken on day 0, before and after leukocyte reducing filtration, 1, 3, 7, and 14. One of the two blood samples from each whole blood product was tested at room temperature and the other was rewarmed to 37°C. The blood samples were mixed with antibodies and platelet agonists and analyzed on a flow cytometer. The blood samples were also analyzed on a cell counter. Results: This study shows distinct changes in platelet spontaneous activation, platelet count, and platelet receptor shedding by increased storage time in cold-stored whole blood and even more with rewarming to 37°C. Conclusion: This study shows that during storage, spontaneous platelet activation and shedding of GPIb and GPIIb increases while platelet count decreases. All these factors are likely affecting the platelet function and hemostatic function negatively.