1.
Age of transfused blood in critically ill adults
Lacroix J, Hebert PC, Fergusson DA, Tinmouth A, Cook DJ, Marshall JC, Clayton L, McIntyre L, Callum J, Turgeon AF, et al
New England Journal of Medicine. 2015;372((15):):1410-8.
Abstract
BACKGROUND Fresh red cells may improve outcomes in critically ill patients by enhancing oxygen delivery while minimizing the risks of toxic effects from cellular changes and the accumulation of bioactive materials in blood components during prolonged storage. METHODS In this multicenter, randomized, blinded trial, we assigned critically ill adults to receive either red cells that had been stored for less than 8 days or standard-issue red cells (the oldest compatible units available in the blood bank). The primary outcome measure was 90-day mortality. RESULTS Between March 2009 and May 2014, at 64 centers in Canada and Europe, 1211 patients were assigned to receive fresh red cells (fresh-blood group) and 1219 patients were assigned to receive standard-issue red cells (standard-blood group). Red cells were stored a mean (+/-SD) of 6.1+/-4.9 days in the fresh-blood group as compared with 22.0+/-8.4 days in the standard-blood group (P<0.001). At 90 days, 448 patients (37.0%) in the fresh-blood group and 430 patients (35.3%) in the standard-blood group had died (absolute risk difference, 1.7 percentage points; 95% confidence interval [CI], -2.1 to 5.5). In the survival analysis, the hazard ratio for death in the fresh-blood group, as compared with the standard-blood group, was 1.1 (95% CI, 0.9 to 1.2; P=0.38). There were no significant between-group differences in any of the secondary outcomes (major illnesses; duration of respiratory, hemodynamic, or renal support; length of stay in the hospital; and transfusion reactions) or in the subgroup analyses. CONCLUSIONS Transfusion of fresh red cells, as compared with standard-issue red cells, did not decrease the 90-day mortality among critically ill adults. (Funded by the Canadian Institutes of Health Research and others; Current Controlled Trials number, ISRCTN44878718.).
2.
The Age of Blood Evaluation (ABLE) randomized controlled trial: study design
Lacroix J, Hebert P, Fergusson D, Tinmouth A, Blajchman MA, Callum J, Cook D, Marshall JC, McIntyre L, Turgeon AF
Transfusion Medicine Reviews. 2011;25((3):):197-205.
Abstract
Red blood cells (RBCs) are transfused to treat anemia and to maintain oxygen delivery to vital organs during critical illness. Laboratory and observational studies have raised the possibility that prolonged RBC storage may adversely affect clinical outcomes. Compared with RBCs stored less than 1 week, there are no clinical data demonstrating that RBCs stored longer remain as effective at carrying or releasing oxygen, and observational studies have risen to possibility that prolonged RBC storage might result in harm to vulnerable patients requiring blood transfusions. The Age of Blood Evaluation(ABLE) study (ISRCTN44878718) is a double-blind, multicenter, parallel randomized controlled clinical trial. It will test the hypothesis that the transfusion of prestorage leukoreduced RBCs stored for 7 days or less (fresh arm) as compared with standard-issue RBCs stored, on average, 15 to 20 days (control arm) will lead to lower 90-day all-cause mortality and reduced morbidity in critically ill adults. We include adults in intensive care units (ICUs) who (1) have had a request for a first RBC unit transfusion during the first 7 days of ICU admission and (2) have an anticipated requirement for ongoing invasive and noninvasive mechanical ventilation exceeding 48 hours. Enrolled patients are randomized at the time of transfusion to receive either standard-issue RBC units or RBCs stored 7 days or less issued by the local hospital transfusion service. The primary outcome is 90-day all-cause mortality. Secondary outcomes include ICU and hospital mortality, organ failure, and serious nosocomial infections. With 2510 patients, we will be able to detect a 5% absolute risk reduction (from 25% to 20%). The ABLE study is currently enrolling patients in 23 university-affiliated and community-hospital ICUs across Canada; sites in France and United Kingdom are expected to start recruitment in 2011. Regardless of the results, ABLE study will have significant implications on the duration of RBC storage. A negative trial will reassure clinicians and blood bankers regarding the effectiveness and safety of standard-issue RBCs. A positive trial will have significant implications with respect to inventory management of RBCs given to critically ill adults with a high risk of mortality and will also prompt research to better understand the RBC storage lesion in the hopes of minimizing its clinical consequences through the development of better storage methods.
3.
Effect of a liberal versus restrictive transfusion strategy on mortality in patients with moderate to severe head injury
McIntyre LA, Fergusson DA, Hutchison JS, Pagliarello G, Marshall JC, Yetisir E, Hare GM, Hébert PC
Neurocritical Care. 2006;5((1):):4-9.
Abstract
OBJECTIVE To compare a restrictive versus a liberal transfusion strategy in patients with moderate to severe closed head injury following multiple trauma in 13 Canadian intensive care units (ICUs). METHODS This is a subgroup analysis of a multicenter randomized controlled clinical trial involving sixty-seven critically ill patients from the Transfusion Requirements in the Critical Care trial who sustained a closed head injury. Patients had a hemoglobin concentration less than 9. 0 g/dL within 72 hours of admission to the ICU. Patients were randomized to a restrictive allogeneic red blood cell transfusion strategy (hemoglobin 7. 0 g/dL and maintained between 7. 0 and 9. 0 g/dL) or a liberal strategy (hemoglobin 10. 0 g/dL and maintained between 10. 0 and 12. 0 g/dL). RESULTS Baseline characteristics in the restrictive ( n = 29) and the liberal ( n = 38) transfusion groups were comparable. Average hemoglobin concentrations and red blood cell units transfused per patient were significantly lower in the restrictive compared to the liberal group. The 30-day all-cause mortality rates in the restrictive group were 17% as compared to 13% in the liberal group (risk difference 4. 1 with 95% confidence interval [CI], 13. 4 to 21. 5, p = 0. 64). Presence of multiple organ dysfunction (12. 1 +/- 6. 4 versus 10. 6 +/- 6. 3, p = 0. 35) and changes in multiple organ dysfunction from baseline scores adjusted for death (4. 5 +/- 6. 2 versus 3. 4 +/- 6. 2, p = 0. 49) were similar between the restrictive and liberal transfusion groups, respectively. Median length of stay in ICU (10 days, interquartile range 5 to 21 days versus 8 days, interquartile range 5 to 11 days, p = 0. 26) and hospital (27 days, interquartile range 14 to 39 days versus 30. 5 days, interquartile range 17 to 47 days, p = 0. 72) were similar between the restrictive and liberal transfusion groups. CONCLUSIONS We were unable to detect significant improvements in mortality with a liberal as compared to restrictive transfusion strategy in critically ill trauma victims with moderate to severe head injury.