Volume-dependent effect of stored red blood cells: A secondary analysis of the Age of Blood Evaluation trial

Department of Medicine, Ottawa General Hospital, University of Ottawa, Ottawa, Ontario, Canada. Department of Medicine and Lady Davis Institute, Jewish General Hospital, McGill University, Montréal, Québec, Canada. Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada. Division of Critical Care, Centre Hospitalier Universitaire de Montréal, Université de Montréal, Montréal, Québec, Canada. Division of Pediatric Critical Care Medicine, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, Québec, Canada.

Transfusion. 2020
BACKGROUND An increased risk of complications, including death, has been associated with stored red blood cell (RBC) units in observational studies but not in randomized trials. We aimed to evaluate for volume-dependent effects attributable to length of RBC storage in a secondary analysis of the Age of Blood Evaluation (ABLE) trial. STUDY DESIGN AND METHODS In the 2510 critically ill adults from the ABLE trial randomized to receive RBC units stored not more than 7 days or the oldest compatible RBC units, we estimated the hazard ratio (HR) for death by intensive care unit (ICU) and hospital discharge and by days 28, 90, and 180, within subgroups defined by the number of RBC units received. Extended Cox proportional hazards regression was used to model the HR. RESULTS A volume-dependent effect of storage age on survival was present for death by 90 and 180 days, but not earlier endpoints. The HR for death by 90 days was 0.55 (95% confidence interval [CI], 0.11-0.98, fresh vs standard) after transfusion of 6 RBC units but 1.45 (95% CI, 1.06-1.98) after transfusion of 1 RBC unit. CONCLUSION In this exploratory analysis, volume-dependent effects related to RBC storage were documented in the ABLE trial. The harms associated with small volumes of fresh RBC units and large volumes of older RBC units should be further explored.
Study details
Language : eng
Credits : Bibliographic data from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine