title: In vitro study of variables relevant to perioperative care of the surgical patient: glucose, osmolarity, and rewarming.
abstract: BACKGROUND
  We sought to determine the effects of altering osmolarity and the reversibility of the detrimental immunologic effects of hypothermia on human monocyte HLA-DR surface expression and reactive oxygen species (ROS) formation.
  
  
  METHODS
  The effects of altering osmolarity on HLA-DR surface expression and ROS formation were assessed using lipopolysaccharide (LPS)-treated samples treated with either saline, glucose, or mannitol, incubated at 37°C for 2 hours. HLA-DR surface receptor expression and ROS formation were determined after incubation. The effects of the reversibility of hypothermia were measured by incubating LPS-treated samples at 34°C, 37°C, and 40°C for 1 hour. The samples were subsequently rewarmed at 40°C for 1 and 2 hours. The effects of rewarming on HLA-DR surface receptor expression and ROS formation were reassessed.
  
  
  RESULTS
  In the osmolarity experiments, there was a 49% decrease in ROS formation in samples treated with mannitol as compared with saline and glucose. Alterations of osmolarity had no significant effect on HLA-DR surface expression. In the rewarming experiments, rewarming for either 1 or 2 hours abolished any significant differences in HLA-DR surface expression and ROS formation between samples preincubated at the different temperatures.
  
  
  CONCLUSIONS
  The presumed inert mannitol was found to significantly decrease ROS formation, but had no effect on HLA-DR surface expression. In addition, the effects of hypothermia on HLA-DR surface expression or ROS formation may be better reversed within 2 hours than in 1 hour.
authors.affiliation: Price Institute of Surgical Research, University of Louisville School of Medicine, Louisville, KY.
authors.forename: Ashley
authors.initials: A
authors.lastname: Dickinson
authors.forename: Motaz
authors.initials: M
authors.lastname: Qadan
authors.forename: Clayton
authors.initials: C
authors.lastname: Weller
authors.forename: Sarah
authors.initials: S
authors.lastname: Gardner
authors.forename: Hiram C
authors.initials: HC
authors.lastname: Polk
mesh_terms: D001786:Blood Glucose / Q000378:metabolism*; D005434:Flow Cytometry; D005947:Glucose / Q000008:administration & dosage; D006684:HLA-DR Antigens / Q000096:biosynthesis*; D006801:Humans; D007035:Hypothermia / Q000097:blood / Q000209:etiology / Q000276:immunology* / Q000628:therapy; D066298:In Vitro Techniques; D008070:Lipopolysaccharides; D008353:Mannitol / Q000008:administration & dosage; D009994:Osmolar Concentration; D019990:Perioperative Care / Q000379:methods* / Q000592:standards*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D017694:Rewarming; D013514:Surgical Procedures, Operative / Q000009:adverse effects; D013696:Temperature
chemical_list: D001786:Blood Glucose; D006684:HLA-DR Antigens; D008070:Lipopolysaccharides; D017382:Reactive Oxygen Species; D008353:Mannitol; D005947:Glucose