A systematic review published by Brunksill et al. in Transfusion Medicine Reviews evaluated existing quality guidelines for RBC exposure to uncontrolled temperature environments. Current standards are that RBCs should be transfused within 4 hours of the unit being removed from a controlled temperature environment and an RBC unit should not be returned to storage and re-issued if the unit was outside a controlled temperature environment for more than 30-minutes. The authors suggest both the “30 minute” and “4-hour” standards may be extended without adverse risks for the RBC unit’s viability, although further research is needed. By reviewing 23 studies which evaluated RBC quality and/or bacterial contamination after exposure to temperatures above 4°C± 2°C for between 20 minutes to 42 days, the authors did not find that temperature exposure decreased RBC quality or increased bacterial contamination. Variation in the studies analyzed, including temperature and duration of exposure, limited the interpretations of this review.
Reference:
Brunskill S, Thomas S, Whitmore E, McDonald CP, Doree C, Hopewell S, Staves J, Cardigan R, Murphy MF. What is the maximum time that a unit of red blood cells can be safely left out of controlled temperature storage? Transfus Med Rev 2012;26: 209-23 e3.