Background: No data exist on the viability of red cells (RBCs) stored in modern additive solution systems and allowed to warm above 10 degrees C.
Study design and methods: In a randomized crossover study, 3 units of blood were collected at least 8 weeks apart from 11 volunteer donors and stored in additive solution 5 (AS-5). Of 3 units from each volunteer, 1 was stored for 6 weeks at 4 degrees C, 1 for 5 weeks at 4 degrees C except for 24 hours at 25 degrees C on Day 14, and 1 for 5 weeks at 4 degrees C except for 24 hours at 25 degrees C on Day 28. Units were sampled periodically during storage; at the end of storage, viability was measured by the 99mTc/51 Cr double-label method.
Results: RBC viability was not significantly different in the storage protocols. Less than 1 percent of stored cells hemolyzed. RBC ATP concentrations at the end of storage correlated with viability and were approximately equal in the warmed units after 30 days' storage and the conventionally stored units after 42 days.
Conclusions: The data suggest that RBCs stored in AS-5 and allowed to warm to 25 degrees C for 24 hours lose about 12 days of their shelf life.