title: Red blood cell transfusion and skeletal muscle tissue oxygenation in anaemic haematologic outpatients.
abstract: BACKGROUND
  Stored red blood cells (RBCs) accumulate biochemical and biophysical changes, known as storage lesion. The aim of this study was to re-challenge current data that anaemia in chronically anaemic haematology patients is not associated with low skeletal muscle tissue oxygen (StO2), and that RBC storage age does not influence the tissue response after ischaemic provocation, using near-infrared spectroscopy.
  
  
  METHODS
  Twenty-four chronic anaemic haematology patients were included. Thenar skeletal muscle StO2was measured at rest (basal StO2), with vascular occlusion testing (upslope StO2, maximum StO2) before and after transfusion.
  
  
  RESULTS
  Basal StO2was low (53% ± 7%). Average RBC storage time was 10.5 ± 3.9 days. Effects of RBC transfusions were as follows: basal StO2and upslope StO2did not change significantly; maximum StO2increased compared to baseline (64 ± 14%vs. 59 ± 10%, p = 0.049). Change of basal StO2, upslope StO2and maximum StO2was negatively related to age of RBCs. The decrease of maximum StO2was predicted (sensitivity 70%, specificity 100%), after receiving RBCs ≥ 10days old.
  
  
  CONCLUSIONS
  Resting skeletal muscle StO2in chronic anaemic patients is low. RBC storage time affects skeletal muscle StO2in the resting period and after ischaemic provocation.
authors.affiliation: Clinical Department for Anaesthesiology and Surgical Intensive Care, University Medical Centre Ljubljana, Slovenia; Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
authors.forename: Matej
authors.initials: M
authors.lastname: Podbregar
authors.affiliation: Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
authors.forename: Ana Ursula
authors.initials: AU
authors.lastname: Gavric
authors.affiliation: Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
authors.forename: Eva
authors.initials: E
authors.lastname: Podbregar
authors.affiliation: Emergency Department, University Medical Centre Ljubljana, Ljubljana, Slovenia.
authors.forename: Hugon
authors.initials: H
authors.lastname: Mozina
authors.affiliation: Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Stefanovic
keywords: red blood cells; skeletal muscle; storage lesion; tissue oxygenation; transfusion