Background: Mechanical stress on red blood cells is associated with using infusion pumps for blood administration. Current standards in North America leave it to healthcare facilities to consult with manufacturers about infusion pump safety for transfusion; studies on various pumps and red blood cell (RBC) conditions are scarce. Study design and methods: RBC units were pumped through four infusion pumps on d22 (22 days postcollection), d40, d28 after gamma irradiation on d14 (I14d28), and d22 after irradiation on d21 (I21d22). For each experiment, three units were pooled and split among four bags. Samples were collected at gravity and after pumping at clinical nonemergency rates. Hemolysis %, microvesicles, potassium, lactate dehydrogenase, mechanical fragility index levels, and morphology evaluations were performed (n = 5-6).Results: Hemolysis levels of Piston and Linear Peristaltic pump samples were not different from hemolysis of corresponding gravity samples. Peristaltic samples had significantly higher hemolysis compared to gravity, and other pumps, however, maximum mean difference was limited to 0.05%. Pumping at 50 mL/h resulted in the highest hemolysis level. Change in hemolysis % due to pumping was significantly higher in d40 and I21d22 units. No combination of pumps and RBCs conditions led to hemolysis >0.8%. Besides hemolysis, lactate dehydrogenase release was the only marker that demonstrated some differences between infusions via pump versus gravity.
Conclusion:The pump design affects the degree of hemolysis. However, for all tested pumps and RBC conditions, this increase was minimal. Hemolysis measurement on d40 and I21d22 at 50 mL/h were concluded to be appropriate parameters for pump evaluation.