A landmark Australian-led five-country research trial has found the transfusion of older stored red blood cells is safe and, surprisingly, associated with fewer side effects in severely ill patients. Routine practice in most hospitals is to allocate the oldest available compatible blood but some doctors request fresher blood for specific patients under the belief that ‘fresh must be best’.
In the TRANSFUSE trial, researchers from the Australian and New Zealand Intensive Care Research Centre at Monash University in Melbourne led teams in 5 countries to investigate the effect of the age of transfused red blood cells on critically ill patient’s outcomes.
In the study, the team demonstrated that fresher blood was no better than older blood. Unexpectedly they also found fewer transfusion reactions, including fever, with the older blood; and in the most severely ill patients, the transfusion of older blood was associated with fewer deaths.
Lead researcher Professor Jamie Cooper said “older blood appears to be like a good red wine- better with some age. The findings of our trial confirm that the current duration of storage of red blood cells for transfusion is both safe and optimal.”
In Australia, red blood cells are stored for up to 42 days before transfusion. Routine practice in most hospitals is to allocate the oldest available compatible blood. Concerns regarding changes in the red blood cells for transfusion during storage, have led some countries to reduce this to 35 days, and some doctors to request fresher blood for specific patients under the belief the “fresh must be best.” “Such practices can significantly reduce the availability of blood for transfusion” said Cooper. “Our study shows these practices are not required and are potentially counterproductive.”
Background: It is uncertain whether the duration of red-cell storage affects mortality after transfusion among critically ill adults.
Methods: In an international, multicenter, randomized, double-blind trial, we assigned critically ill adults to receive either the freshest available, compatible, allogeneic red cells (short-term storage group) or standard-issue (oldest available), compatible, allogeneic red cells (long-term storage group). The primary outcome was 90-day mortality.
Results: From November 2012 through December 2016, at 59 centers in five countries, 4994 patients underwent randomization and 4919 (98.5%) were included in the primary analysis. Among the 2457 patients in the short-term storage group, the mean storage duration was 11.8 days. Among the 2462 patients in the long-term storage group, the mean storage duration was 22.4 days. At 90 days, there were 610 deaths (24.8%) in the short-term storage group and 594 (24.1%) in the long-term storage group (absolute risk difference, 0.7 percentage points; 95% confidence interval [CI], −1.7 to 3.1; P=0.57). At 180 days, the absolute risk difference was 0.4 percentage points (95% CI, −2.1 to 3.0; P=0.75). Most of the prespecified secondary measures showed no significant between-group differences in outcome.
Conclusions: The age of transfused red cells did not affect 90-day mortality among critically ill adults.
D James Cooper, Zoe K McQuilten, Alistair Nichol, Bridget Ady, Cécile Aubron, Michael Bailey, Rinaldo Bellomo, Dashiell Gantner, David O Irving, Kirsi-Maija Kaukonen, Colin McArthur, Lynne Murray, Ville Pettilä, Craig French