title: Red blood cells stored 35 days or more are associated with adverse outcomes in high-risk patients.
abstract: Clinical trials have shown that longer red blood cell (RBC) storage duration does not worsen outcomes; however, these studies included few RBCs near the end of the 42-day storage limit. We tested the hypothesis that these "oldest" RBCs are associated with adverse outcomes.
  
  
  
  In a retrospective study, 28,247 transfused patients given 129,483 RBC units were assessed. Morbidity, mortality, and length of stay (LOS) were compared in patients transfused exclusively with RBCs stored not more than 21 days versus patients transfused exclusively with RBCs stored 28 days or more and patients transfused exclusively with RBCs stored 35 days or more.
  
  
  
  After risk adjustment, ≥35-day RBCs were associated with increased morbidity (adjusted odds ratio [adjOR], 1.19; 95% confidence interval [CI], 1.07-1.32; p = 0.002), but ≥28-day RBCs were not (adjOR, 1.06; 95% CI, 0.97-1.15; p = 0.2). Neither ≥35-day nor ≥28-day RBCs were associated with increased mortality. In critically ill patients, ≥35-day RBCs were associated with increased morbidity (adjOR, 1.25; 95% CI, 1.08-1.44; p = 0.002) and mortality (adjOR, 1.38; 95% CI, 1.08-1.74; p = 0.009), but ≥28-day RBCs were associated with neither. In older patients, ≥35-day RBCs were associated with increased morbidity (adjOR, 1.22; 95% CI, 1.04-1.42; p = 0.01), but not mortality (adjOR, 1.28; 95% CI, 0.96-1.71; p = 0.1), and ≥28-day RBCs were associated with neither. LOS was increased for both ≥28- and ≥35-day RBCs for all patients and the critically ill and older subgroups.
  
  
  
  RBCs transfused in the last 7 days of their 42-day storage limit may be associated with adverse clinical outcomes in high-risk patients.
authors.affiliation: Departments of Pathology and Pediatric Hematology/Oncology, New York Presbyterian Hospital, Weill Cornell Medical College, and The New York Blood Center, New York, New York.
authors.forename: Ruchika
authors.initials: R
authors.lastname: Goel
authors.affiliation: Department of Anesthesiology/Critical Care Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Johnson
authors.affiliation: Department of Anesthesiology/Critical Care Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Andrew V
authors.initials: AV
authors.lastname: Scott
authors.affiliation: Department of Pathology (Transfusion Medicine), The Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Aaron A R
authors.initials: AA
authors.lastname: Tobian
authors.affiliation: Department of Pathology (Transfusion Medicine), The Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Ness
authors.affiliation: Department of Anesthesiology/Critical Care Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Enika
authors.initials: E
authors.lastname: Nagababu
authors.affiliation: Department of Anesthesiology/Critical Care Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Frank
mesh_terms: D000328:Adult; D000368:Aged; D001793:Blood Preservation / Q000592:standards*; D016638:Critical Illness; D017707:Erythrocyte Transfusion / Q000009:adverse effects*; D004912:Erythrocytes; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012306:Risk; D013997:Time Factors