title: The effect of blood storage duration on in-hospital mortality: a randomized controlled pilot feasibility trial.
abstract: BACKGROUND
  Whether the duration of storage of blood has an impact on patient outcomes remains controversial. The objective was to determine feasibility of a comparative effectiveness trial to evaluate duration of storage of blood before transfusion on in-hospital mortality.
  
  
  METHODS
  A single-center randomized controlled trial was performed at an acute care hospital in Canada between June and December 2010, involving consecutive hospitalized patients needing blood transfusion. Patients (n=910) were randomly assigned in a 1:2 ratio to receive freshest available versus standard-issue (oldest available) blood. Four feasibility criteria were measured: proportion of eligible patients randomized, contrast in age of blood between treatment groups, real-time data acquisition, and trial impact on blood outdating. In-hospital mortality was also reported.
  
  
  RESULTS
  A total of 1075 of 1129 patients (95.2%) were eligible and 910 of 1075 (84.7%) were randomized: 309 received freshest available blood (1157 units), and 601 received standard-age blood (2369 units). Contrast in mean age of the oldest blood transfused between groups was 14.6 days: 12.0 (standard deviation [SD], 6.8) days in the fresh arm and 26.6 (SD, 7.8) days in the standard arm. Weekly recruitment and event reporting were achieved for all patients. The blood outdate rate was 0.10%. In-hospital mortality was 10.5%: 35 deaths (11.3%) in the fresh arm and 61 deaths (10.1%) in the standard arm (odds ratio, 1.13; 95% confidence interval [CI], 0.73, 1.76).
  
  
  CONCLUSIONS
  It is feasible to conduct a large comparative effectiveness trial comparing the effect of freshest available versus standard-issue blood on in-hospital mortality. The wide CI around the estimate for in-hospital mortality supports the need for a large trial.
authors.affiliation: Department of Medicine, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada. heddlen@mcmaster.ca
authors.forename: Nancy M
authors.initials: NM
authors.lastname: Heddle
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Cook
authors.forename: Donald M
authors.initials: DM
authors.lastname: Arnold
authors.forename: Mark A
authors.initials: MA
authors.lastname: Crowther
authors.forename: Theodore E
authors.initials: TE
authors.lastname: Warkentin
authors.forename: Kathryn E
authors.initials: KE
authors.lastname: Webert
authors.forename: Jack
authors.initials: J
authors.lastname: Hirsh
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Barty
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Connie
authors.initials: C
authors.lastname: Lester
authors.forename: John W
authors.initials: JW
authors.lastname: Eikelboom
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001793:Blood Preservation / Q000009:adverse effects / Q000401:mortality* / Q000592:standards; D058731:Blood Safety / Q000379:methods / Q000401:mortality; D001803:Blood Transfusion / Q000401:mortality*; D002170:Canada / Q000453:epidemiology; D057186:Comparative Effectiveness Research / Q000379:methods; D005240:Feasibility Studies; D005260:Female; D017052:Hospital Mortality; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D013997:Time Factors; D055815:Young Adult