Hemolysis of red blood cells during processing and storage

BACKGROUND: During processing and storage, red blood cells (RBCs) undergo changes and cell injury resulting in hemolysis. Mostly, the separation of whole blood in top‐and‐bottom quadruple bag systems with break openings takes less than 4 minutes. However, longer separation times are not uncommon. The aims were to investigate whether hemolysis is increased in RBCs with longer separation time (RBCs>6 min) compared to regular RBCs (RBCsreg), to measure hemolysis increase during storage and to study whether frequency of hemolytic donations is donor dependent.STUDY DESIGN AND METHODS: RBCs>6 min (n = 172) and 172 matched controls were tested for hemolysis on Days 1 and 21 RBC units from each group were stored at 4 ± 2°C and tested again after 5 weeks. Donor dependency was retrospectively investigated for 100 hemolytic RBC units.RESULTS: RBCs>6 min exhibited a higher mean hemolysis rate than RBCsreg (0.058% vs. 0.033%). Four RBC units were hemolytic (>0.8%), all RBCs>6 min (2.36%). During storage, hemolysis in both groups increased with 0.24%. Hemolysis frequency did not seem to be donor dependent.CONCLUSIONS: Increased separation time is a useful screening tool for potentially increased hemolysis rate in RBCs. Hemolysis rate increased during storage equally in both groups. Hemolysis frequency appears donor independent.