title: Cryopreserved red blood cells are superior to standard liquid red blood cells.
abstract: BACKGROUND
  Liquid preserved packed red blood cell (LPRBC) transfusions are used to treat anemia and increase end-organ perfusion. Throughout their storage duration, LPRBCs undergo biochemical and structural changes collectively known as the storage lesion. These changes adversely affect perfusion and oxygen off-loading. Cryopreserved RBCs (CPRBC) can be stored for up to 10 years and potentially minimize the associated storage lesion. We hypothesized that CPRBCs maintain a superior biochemical profile compared with LPRBCs.
  
  
  METHODS
  This was a prospective, randomized, double-blinded study. Adult trauma patients with an Injury Severity Score (ISS) greater than 4 and an anticipated 1-U to 2-U transfusion of PRBCs were eligible. Enrolled patients were randomized to receive either CPRBCs or LPRBCs. Serum proteins (haptoglobin, serum amyloid P, and C-reactive protein), proinflammatory and anti-inflammatory cytokines, d-dimer, nitric oxide, and 2,3-DPG concentrations were analyzed. Mann-Whitney U-test and Wilcoxon rank sum test were used to assess significance (p < 0.05).
  
  
  RESULTS
  Fifty-seven patients were enrolled (CPRBC, n = 22; LPRBC, n = 35). The LPRBC group's final interleukin 8, tumor necrosis factor α, and d-dimer concentrations were elevated compared with their pretransfusion values (p < 0.05). After the second transfused units, 2,3-DPG was higher in the patients receiving CPRBCs (p < 0.05); this difference persisted throughout the study. Finally, serum protein concentrations were decreased in the transfused CPRBC units compared with LPRBC (p < 0.01).
  
  
  CONCLUSIONS
  CPRBC transfusions have a superior biochemical profile: an absent inflammatory response, attenuated fibrinolytic state, and increased 2,3-DPG. A blood banking system using both storage techniques will offer the highest-quality products to critically injured patients virtually independent of periodic changes in donor availability and transfusion needs.
  
  
  METHODS
  Therapeutic study, level II.
authors: From the Oregon Health and Science University, Division of Trauma, Critical Care and Acute Care Surgery, Trauma Research Institute of Oregon (D.A.H., L.J.F., L.K., J.D., S.U., D.L., J.W., M.A.S.); and Portland State University (C.W.),Portland, Oregon.
authors: David A
authors: DA
authors: Hampton
authors: Connor
authors: C
authors: Wiles
authors: Loïc J
authors: LJ
authors: Fabricant
authors: Laszlo
authors: L
authors: Kiraly
authors: Jerome
authors: J
authors: Differding
authors: Samantha
authors: S
authors: Underwood
authors: Dinh
authors: D
authors: Le
authors: Jennifer
authors: J
authors: Watters
authors: Martin A
authors: MA
authors: Schreiber
mesh_terms: D001771:Blood Banks; D001793:Blood Preservation / Q000379:methods*; D015925:Cryopreservation; D016207:Cytokines / Q000097:blood; D004311:Double-Blind Method; D017707:Erythrocyte Transfusion / Q000379:methods; D004912:Erythrocytes; D006801:Humans; D010865:Pilot Projects; D011446:Prospective Studies
chemical_list: D016207:Cytokines