Hemostatic function of cold-stored platelets in a thrombocytopenic rabbit bleeding model

Area of Science:

• Hematology
• Transfusion Medicine
• Thrombosis and Hemostasis

Background:

• Cold-stored platelet concentrates (CS-PCs) are increasingly used for massive bleeding.
• Their in vivo hemostatic function in severe thrombocytopenia remains under-evaluated.
• This study investigates the efficacy of CS-PCs in a preclinical model of thrombocytopenia.

Purpose of the Study:

• To evaluate the in vivo hemostatic function of plasma-depleted human CS-PCs compared to room temperature-stored (RTS) PCs.
• To assess the efficacy of these transfusions in rabbits with induced severe thrombocytopenia.
• To determine if storage temperature affects platelet hemostatic performance.

Main Methods:

• Human apheresis platelets were processed and stored at cold (4°C) or room temperature (20-24°C) in platelet additive solution (PAS).
• Rabbits with busulfan-induced thrombocytopenia and a blocked reticuloendothelial system received transfusions of RTS- or CS-PAS-PCs.
• Hemostatic efficacy was measured by ear bleeding time, and platelet counts were monitored post-transfusion.

Main Results:

• Both RTS- and CS-PAS-PCs achieved 100% hemostasis on day 3.
• On days 6 and 9, hemostatic rates were comparable between RTS- and CS-PAS-PCs, although not statistically significant (p > 0.05).
• Platelet counts were significantly lower after CS-PAS-PC transfusion compared to RTS-PAS-PC, particularly on day 9 (p=0.0007).

Conclusions:

• CS-PAS-PCs may provide similar hemostasis to RTS-PAS-PCs in thrombocytopenic patients with mild bleeding.
• Higher doses of CS-PAS-PCs might be necessary to achieve optimal hemostatic efficacy.
• Further studies are warranted to optimize CS-PC transfusion strategies.