title: In vitro effects of three formulations of hydroxyethyl starch solutions on coagulation and platelet function in horses.
abstract: OBJECTIVE
  To investigate the in vitro effects of 3 hydroxyethyl starch (HES) solutions on viscoelastic coagulation testing and platelet function in horses.
  
  
  METHODS
  Blood samples collected from 7 healthy adult horses.
  
  
  METHODS
  Blood samples were diluted with various crystalloid and HES solutions to approximate the dilution of blood in vivo that occurs with administration of a 10 and 20 mL/kg fluid bolus to a horse (1:8 and 1:4 dilutions, respectively). Diluted samples were analyzed through optical platelet aggregometry, platelet function analysis, thromboelastography, and dynamic viscoelastic coagulometry. Colloid osmotic pressure and concentrations of von Willebrand factor and factor VIII:C were also determined for each sample.
  
  
  RESULTS
  For all HES products, at both dilutions, the colloid osmotic pressure was significantly higher than that in the respective carrier solutions. At the 1:4 dilution, nearly all HES solutions resulted in significant alterations in platelet function as measured via the platelet function analyzer and dynamic viscoelastic coagulometer. Significant decreases in platelet aggregation and factor concentrations were also evident. Fewer HES-associated changes were identified at the 1:8 dilutions.
  
  
  CONCLUSIONS
  Dilution of blood samples with all HES solutions resulted in changes in viscoelastic coagulation and platelet function that did not appear to be attributable to dilution alone. In vivo evaluations are necessary to understand the clinical impact of these in vitro changes.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA. aeb287@cornell.edu
authors.forename: April E
authors.initials: AE
authors.lastname: Blong
authors.forename: Kira L
authors.initials: KL
authors.lastname: Epstein
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Brainard
mesh_terms: D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects*; D001792:Blood Platelets / Q000187:drug effects*; D005260:Female; D006736:Horses / Q000097:blood*; D006895:Hydroxyethyl Starch Derivatives / Q000737:chemistry* / Q000494:pharmacology*; D007552:Isotonic Solutions; D008297:Male; D010974:Platelet Aggregation / Q000187:drug effects*; D000077325:Ringer's Lactate
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D007552:Isotonic Solutions; D000077325:Ringer's Lactate