title: Factors affecting red blood cell storage age at the time of transfusion.
abstract: BACKGROUND
  Clinical trials are investigating the potential benefit resulting from a reduced maximum storage interval for red blood cells (RBCs). The key drivers that determine RBC age at the time of issue vary among individual hospitals. Although progressive reduction in the maximum storage period of RBCs would be expected to result in smaller hospital inventories and reduced blood availability, the magnitude of the effect is unknown.
  
  
  METHODS
  Data on current hospital blood inventories were collected from 11 hospitals and three blood centers in five nations. A general predictive model for the age of RBCs at the time of issue was developed based on considerations of demand for RBCs in the hospital.
  
  
  RESULTS
  Age of RBCs at issue is sensitive to the following factors: ABO group, storage age at the time of receipt by the hospital, the restock interval, inventory reserve, mean demand, and variation in demand.
  
  
  CONCLUSIONS
  A simple model, based on hospital demand, may serve as the basis for examining factors affecting the storage age of RBCs in hospital inventories. The model suggests that the age of RBCs at the time of their issue to the patient depends on factors external to the hospital transfusion service. Any substantial change in the expiration date of stored RBCs will need to address the broad variation in demand for RBCs while attempting to balance considerations of availability and blood wastage.
authors.affiliation: Massachusetts General Hospital, Boston, Massachusetts; Filton Blood Centre, Bristol, UK; John Radcliffe Hospital, National Blood Service, Oxford, UK; University of Washington, Seattle, Washington; New Zealand Blood Service, Auckland, New Zealand; Fletcher Allen Health Care, Burlington, Vermont; Hema Quebec, Ste-Foy, Quebec, Canada; Beth Israel Deaconess Medical Center, Boston, Massachusetts; Hospital Clinic Provincial, Barcelona, Spain; Hoxworth Blood Center, Cincinnati, Ohio; Sírio Libanês Hospital, São Paulo, Brazil; Dartmouth-Hitchcock Medical Center, Lebanon, NH.
authors.forename: Walter H
authors.initials: WH
authors.lastname: Dzik
authors.forename: Neil
authors.initials: N
authors.lastname: Beckman
authors.forename: Michael F
authors.initials: MF
authors.lastname: Murphy
authors.forename: Meghan
authors.initials: M
authors.lastname: Delaney
authors.forename: Peter
authors.initials: P
authors.lastname: Flanagan
authors.forename: Mark
authors.initials: M
authors.lastname: Fung
authors.forename: Marc
authors.initials: M
authors.lastname: Germain
authors.forename: Richard L
authors.initials: RL
authors.lastname: Haspel
authors.forename: Miguel
authors.initials: M
authors.lastname: Lozano
authors.forename: Ronald
authors.initials: R
authors.lastname: Sacher
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Szczepiorkowski
authors.forename: Silvano
authors.initials: S
authors.lastname: Wendel
mesh_terms: D001793:Blood Preservation / Q000379:methods*; D001803:Blood Transfusion; D017707:Erythrocyte Transfusion; D004912:Erythrocytes; D006801:Humans; D013997:Time Factors