Photo by Elise Amendola
The length of time red blood cells (RBCs) are stored does not affect transfusion outcomes in critically ill patients, results of the ABLE study suggest.
Researchers compared critically ill patients who received RBCs stored for an average of about 3 weeks to those who received RBCs stored for less than a week.
And there were no significant differences between the groups with regard to mortality, transfusion reactions, and other outcomes.
“Previous observational and laboratory studies have suggested that fresh blood may be better because of the breakdown of red blood cells and accumulation of toxins during storage,” said Alan Tinmouth, MD, of the University of Ottawa in Ontario, Canada.
“But this definitive clinical trial clearly shows that these changes do not affect the quality of blood.”
Dr Tinmouth and his colleagues reported these results in NEJM.
The researchers enrolled 2430 adult intensive care patients in the trial, comparing patients who received fresh RBCs (n=1211) to those who received older RBCs (n=1219). Fresh RBCs were stored for a median of 6.1±4.9 days, and older RBCs were stored for a median of 22.0±8.4 days.
There was no significant difference between the arms with regard to the primary outcome, 90-day mortality. This endpoint was met by 37% of patients who received fresh blood and 35.3% of those who received older blood.
There were no significant differences between the fresh and older RBC arms for other mortality outcomes, either. This included death in the intensive care unit (26.7% vs 24.2%), in-hospital death (33.3% vs 31.9%), and death by day 28 (30.6% vs 28.8%).
Similarly, there were no significant differences between the fresh and older blood arms with regard to major illnesses, including multiple organ dysfunction syndrome (13.4% vs 13%), acute respiratory distress syndrome (5.7% vs 6.6%), cardiovascular failure (5.1% vs 4.2%), cardiac ischemia or infarction (4.5% vs 3.6%), venous thromboembolism (3.6% for both), nosocomial infection (34.1% vs 31.3%), and acute transfusion reaction (0.3% vs 0.5%).
In addition, there was no significant difference between the fresh RBC arm and the older RBC arm in the length of time patients required mechanical ventilation (15.0±18.0 days vs 14.7±14.9 days), cardiac or vasoactive drugs (7.1±10.2 days vs 7.5±11.2 days), or extrarenal epuration (2.5±10.1 days vs 2.5±8.3 days).
And there was no significant difference between the fresh and older blood arms in patients’ length of stay in the hospital (34.4±39.5 days vs 33.9±38.8 days) or the intensive care unit (15.3±15.4 days vs 15.3±14.8 days).
Based on these results, the researchers said there is no need to worry about the age of blood routinely used in hospitals. The team is now conducting a trial to determine if the same can be said for transfusions in pediatric patients.
