title: Transfusion of packed red blood cells reduces selenium levels  and increases lipid peroxidation in an in vivo ovine model.
abstract: BACKGROUND
  Oxidative stress from surgery or critically illness has been shown to adversely contribute to morbidity and mortality. Recent studies record that oxidative stress is heightened following packed red blood cell (PRBC) transfusions and that products of oxidative stress accumulate as the PRBC ages. However, there are no studies that investigate if transfusion of aged PRBC actually increases the recipient's oxidative stress profile more than fresh PRBC.
  
  
  OBJECTIVE
  To compare the effect of fresh vs aged PRBC transfusions on the recipient's oxidative stress using an ovine model.
  
  
  METHODS
  Male sheep were transfused with either fresh (n = 6) or aged (n = 6) ovine PRBC, and serial blood samples taken. Plasma samples were analysed for lipid peroxidation using the thiobarbituric acid reactive substances (TBARS) assay. This served as an indicator of oxidative injury. Antioxidant function and trace element levels were also measured.
  
  
  RESULTS
  Like human PRBC, the ovine PRBC had negligible selenium levels. Irrespective of age, PRBC transfusion was associated with reduced selenium levels and antioxidant function, which correlated with increased markers of lipid peroxidation.
  
  
  CONCLUSIONS
  Transfusion of selenium poor PRBC can dilute selenium levels and compromise glutathione peroxidase antioxidant activity and thereby allow lipid peroxidation. As there was no evidence that aged PRBC induced more severe oxidative injury this suggests that selenium dilution is a key underlying mechanism. Further studies are needed to assess the impact of transfusion-related oxidative stress in massive transfusions.
authors.forename: C I
authors.initials: CI
authors.lastname: McDonald
authors.forename: J F
authors.initials: JF
authors.lastname: Fraser
authors.forename: K
authors.initials: K
authors.lastname: Shekar
authors.forename: K R
authors.initials: KR
authors.lastname: Dunster
authors.forename: O
authors.initials: O
authors.lastname: Thom
authors.forename: Y L
authors.initials: YL
authors.lastname: Fung
mesh_terms: D000818:Animals; D001793:Blood Preservation / Q000009:adverse effects; D017707:Erythrocyte Transfusion; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008954:Models, Biological; D018384:Oxidative Stress; D012643:Selenium / Q000097:blood*; D012756:Sheep; D013997:Time Factors
chemical_list: D012643:Selenium