title: Red blood cell transfusions and tissue oxygenation in anemic hematology outpatients.
abstract: BACKGROUND
  There is little clinical evidence that red blood cell (RBC) transfusions improve oxygen availability at the microcirculatory level. We tested the hypotheses that anemia in chronically anemic patients with relatively healthy microcirculation would be associated with low tissue hemoglobin (Hb) and tissue oxygenation levels and that these conditions would be improved after RBC transfusions.
  
  
  METHODS
  Near-infrared spectroscopy (NIRS) was used to determine tissue oxygen saturation (StO(2)) and tissue Hb index (THI; an index of the amount of Hb in the NIRS measurement volume) in the thenar eminence and sublingual tissue before and 30 minutes after RBC transfusions in 20 chronically anemic hematology outpatients. Data are presented as median (25%-75%).
  
  
  RESULTS
  The patients received three (two to three) bags of RBCs in saline-adenine-glucose-mannitol with an age of 21 (7-21) days, which was infused intravenously at the rate of 0.7 bag/hr. RBC transfusions significantly increased hematocrit level from 26% (24%-28%) to 32% (30%-34%; p < 0.0001), Hb level from 8.2 (7.6-8.9) g/dL to 11.0 (9.9-11.8) g/dL (p < 0.0001), whole blood viscosity from 3.4 (3.1-3.5) mPa/sec to 4.2 (4.0-4.5) mPa/sec (p < 0.0001), thenar StO(2) from 81% (80%-84%) to 86% (81%-89%; p = 0.002), thenar THI from 11.2 (9.3-13.3) AU to 13.7 (9.7-15.3) AU (p = 0.024), sublingual StO(2) from 86% (81%-89%) to 91% (86%-92%; p < 0.0001), and sublingual THI from 15.2 (13.0-17.4) AU to 17.2 (13.5-19.7) AU (p = 0.040).
  
  
  CONCLUSIONS
  Although anemia in chronically anemic hematology outpatients was not associated with low StO(2) and THI levels, RBC transfusions were successful in improving these variables.
authors: Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands. k.yuruk@amc.uva.nl
authors: Koray
authors: K
authors: Yuruk
authors: Sebastiaan A
authors: SA
authors: Bartels
authors: Dan M J
authors: DM
authors: Milstein
authors: Rick
authors: R
authors: Bezemer
authors: Bart J
authors: BJ
authors: Biemond
authors: Can
authors: C
authors: Ince
mesh_terms: D000368:Aged; D000740:Anemia / Q000097:blood* / Q000628:therapy*; D002908:Chronic Disease; D017707:Erythrocyte Transfusion; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D010045:Outpatients; D010092:Oximetry; D010100:Oxygen / Q000097:blood*; D019265:Spectroscopy, Near-Infrared; D016896:Treatment Outcome
chemical_list: D006454:Hemoglobins; D010100:Oxygen