title: Impact of transfusion of autologous 7- versus 42-day-old AS-3 red blood cells on tissue oxygenation and the microcirculation in healthy volunteers.
abstract: BACKGROUND
  Stored red blood cells (RBCs) accumulate biochemical and biophysical changes. Maximum storage duration is based on acceptable in vitro characteristics and 24-hour survival, but not RBC function. Relatively little is known about the impact of RBC storage duration on oxygenation and the microcirculation.
  
  
  METHODS
  Eight healthy subjects donated a double RBC apheresis, which were prestorage leukoreduced and processed in AS-3. Subjects were transfused 1 unit of RBCs at 7 and 42 days after blood collection. Measurements of percentage of tissue oxygenation in the thenar eminence muscle (StO2) and brain (SctO2) were recorded with Food and Drug Administration-cleared noninvasive devices. Sublingual microvascular blood flow (microcirculatory flow index [MFI]) was quantified before and after RBC transfusion using a video microscope. Raw electronic data for all measurements were analyzed by a blinded observer at a core laboratory.
  
  
  RESULTS
  The only pre- versus posttransfusion change observed in measurements of SctO2, StO2, or MFI was a very small increase in SctO2, from 70.4 to 71.8 (means, p=0.032) at 7 days. There was no significant difference in the amount of pre-post change at 7 days versus 42 days for any of the measures.
  
  
  CONCLUSIONS
  Transfusion of 1 unit of 42-day-stored RBCs to healthy subjects has no overt detrimental effect on tissue oxygenation or the microcirculation assessed by clinically available monitors.
authors.affiliation: Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: Russell S
authors.initials: RS
authors.lastname: Roberson
authors.forename: Evelyn
authors.initials: E
authors.lastname: Lockhart
authors.forename: Nathan I
authors.initials: NI
authors.lastname: Shapiro
authors.forename: Nicholas
authors.initials: N
authors.lastname: Bandarenko
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: McMahon
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Massey
authors.forename: William D
authors.initials: WD
authors.lastname: White
authors.forename: Elliott
authors.initials: E
authors.lastname: Bennett-Guerrero
mesh_terms: D019794:2,3-Diphosphoglycerate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D001781:Blood Component Removal; D001793:Blood Preservation / Q000379:methods* / Q000592:standards*; D001804:Blood Transfusion, Autologous / Q000379:methods / Q000592:standards; D017707:Erythrocyte Transfusion / Q000379:methods* / Q000592:standards*; D004912:Erythrocytes / Q000166:cytology / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology*; D009060:Mouth Floor / Q000098:blood supply; D010100:Oxygen / Q000097:blood*; D012016:Reference Values; D015203:Reproducibility of Results; D013997:Time Factors; D055815:Young Adult
chemical_list: D019794:2,3-Diphosphoglycerate; D000255:Adenosine Triphosphate; D010100:Oxygen