title: Blood storage alters mechanical stress responses of erythrocytes.
abstract: BACKGROUND
  Erythrocytes undergo irreversible morphological and biochemical changes during storage. Reduced levels of deformability have been reported for stored erythrocytes. Erythrocyte deformability is essential for healthy microcirculation.
  
  
  OBJECTIVE
  The aim of this study is to evaluate shear stress (SS) induced improvements of erythrocyte deformability in stored blood.
  
  
  METHODS
  Deformability changes were evaluated by applying physiological levels of SS (5 and 10 Pa) in metabolically depleted blood for 48 hours and stored blood for 35 days with citrate phosphate dextrose adenine-1 (CPDA-1). Laser diffractometry was used to measure erythrocyte deformability before and after application of SS.
  
  
  RESULTS
  Erythrocyte deformability, as a response to continuous SS, was significantly improved in metabolically depleted blood, whereas it was significantly impaired in the blood stored for 35 days with CPDA-1 (p≤0.05). The SS-induced improvements of deformability were deteriorated due to storage and relatively impaired according to the storage time. However, deformability of stored blood after exposure to mechanical stress tends to increase at low levels of shear while decreasing at high SS levels.
  
  
  CONCLUSIONS
  Impairment of erythrocyte deformability after storage may contribute to impairments in the recipient's microcirculation after blood transfusion. The period of the storage should be considered to prevent microcirculatory problems and insufficient oxygen delivery to the tissues.
authors.forename: Elif
authors.initials: E
authors.lastname: Ugurel
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Kucuksumer
authors.forename: Buse
authors.initials: B
authors.lastname: Eglenen
authors.forename: Ozlem
authors.initials: O
authors.lastname: Yalcin
mesh_terms: D001793:Blood Preservation / Q000379:methods*; D004907:Erythrocyte Deformability / Q000502:physiology*; D004912:Erythrocytes / Q000502:physiology*; D006801:Humans; D013314:Stress, Mechanical
keywords: CPDA-1; Erythrocyte deformability; blood storage; metabolic depletion; shear stress