In vitro hemolysis of stored units of canine packed red blood cells.

Background: Hemolysis is an important quality parameter of packed red blood cells (pRBCs) that is used to assess the cellular integrity of stored blood units. According to human standards, hemolysis at the end of storage must not exceed 1%, as otherwise it may be responsible for decreased transfusion effectiveness and acute life-threatening reactions.

Objectives: This prospective study was designed to evaluate the hemolysis of canine pRBCs stored in an additive solution containing adenine, dextrose, mannitol, and sodium chloride, and to assess its associations with storage time, duration of the collection process, collection disturbances, and with the final volume and PCV of the pRBCs units.

Methods: One hundred eighty pRBCs units were collected from canine donors. Hemolysis of the pRBCs units was determined immediately after processing (t = 0). The units were then stored and retested (t = 1) either before administration (during weeks 2, 3, 4, 5, or 6 of storage) or at the end of the storage period (42 d) if not used.

Results: Mean hemolysis at t = 0 was 0.09% (SD 0.06) and increased during storage, at a more pronounced rate from the 5th (mean values of 0.52%, SD 0.29) to the 6th week (1.2%, SD 0.72). Almost 51% of the units with 36-42 days of shelf-life showed more than 1% hemolysis. Disturbances in the collection process, the volume of the whole blood units, and the volume of stored pRBCs units or their PCV were not related to pRBCs hemolysis.

Conclusions: According to human blood bank recommendations regarding acceptable hemolysis, canine pRBCs stored for more than 35 days should be tested to ensure <1% hemolysis prior to administration.