title: Microcirculatory hemodynamics after acute blood loss followed by fresh and banked blood transfusion.
abstract: BACKGROUND
  Red blood cell (RBC) conformational changes occur when blood is stored. This study was designed to be a preliminary evaluation to assess how these changes affect the microcirculation.
  
  
  METHODS
  The rat cremaster muscle flap model was used to evaluate in vivo microcirculatory changes after withdrawal of 1 mL blood with subsequent administration of fresh blood (group I, n=6) and banked blood (group II, n=6). Each group underwent a 3-stage evaluation: baseline, after blood withdrawal, and after transfusion. Using intravital microscopy, RBC velocity, vessel diameter, functional capillary perfusion, and leukocyte-endothelial interactions were noted.
  
  
  RESULTS
  After blood withdrawal, changes in RBC velocity, vessel diameter, functional capillary perfusion, and number of activated leukocytes were observed in both groups, but these changes were more significant in stored blood compared with fresh blood (P<or=.05).
  
  
  CONCLUSIONS
  Further work is needed to validate these findings, but these preliminary data suggest that stored blood may have a deleterious effect on the microcirculation.
authors.affiliation: Department of Plastic Surgery, The Cleveland Clinic Foundation, 9500 Euclid Ave., Cleveland, OH 44195, USA.
authors.forename: Emrah
authors.initials: E
authors.lastname: Arslan
authors.forename: Emilia
authors.initials: E
authors.lastname: Sierko
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Waters
authors.forename: Maria
authors.initials: M
authors.lastname: Siemionow
mesh_terms: D000818:Animals; D001771:Blood Banks; D001800:Blood Specimen Collection; D001803:Blood Transfusion; D004730:Endothelium, Vascular / Q000276:immunology; D006439:Hemodynamics; D006470:Hemorrhage / Q000503:physiopathology / Q000628:therapy*; D007962:Leukocytes / Q000378:metabolism; D008213:Lymphocyte Activation; D008297:Male; D008833:Microcirculation / Q000502:physiology*; D018482:Muscle, Skeletal / Q000098:blood supply; D010100:Oxygen / Q000097:blood; D051381:Rats; D011917:Rats, Inbred Lew; D018709:Statistics, Nonparametric
chemical_list: D010100:Oxygen