title: In vitro effects of 6 % hydroxyethyl starch 130/0.42 solution on feline whole blood coagulation measured by rotational thromboelastometry.
abstract: BACKGROUND
  The artificial colloid, hydroxyethyl starch (HES), is recommended for intravascular volume expansion and colloid-osmotic pressure enhancement in dogs and cats. A well-known side effect of HES solutions in humans and dogs is coagulopathy. However, HES-associated coagulopathy has thus far not been investigated in cats. The goal of this study was to assess the in vitro effects of 6 % HES 130/0.42 on feline whole blood samples using rotational thromboelastometry (ROTEM). A further goal was to develop feline reference intervals for ROTEM at our institution. In this in vitro experimental study, blood samples of 24 adult healthy cats were collected by atraumatic jugular phlebotomy following intramuscular sedation. Baseline ROTEM analyses (using ex-tem, in-tem and fib-tem assays) were performed in duplicate. Additionally, ROTEM analyses were performed on blood samples after dilution with either Ringer's acetate (RA) or 6 % HES 130/0.42 (HES) in a 1:6 dilution (i.e. 1 part solution and 6 parts blood).
  
  
  RESULTS
  Coefficients of variation of duplicate measures were below 12 % in all ex-tem assays, 3 of 4 in-tem assays but only 1 of 3 fib-tem assays. Reference intervals were similar albeit somewhat narrower than those previously published. Dilution with both solutions lead to significantly prolonged CT (in-tem), CFT (ex-tem and in-tem), and reduced MCF (ex-tem, in-tem, and fib-tem) and alpha (ex-tem and in-tem). Compared to RA, dilution with HES caused a significant prolongation of CT in fib-tem (P = 0.016), CFT in ex-tem (P = 0.017) and in-tem (P = 0.019), as well as a reduction in MCF in in-tem (P = 0.032) and fib-tem (P = 0.020), and alpha in ex-tem (P = 0.014). However, only a single parameter (CFT in ex-tem) was outside of the established reference interval after dilution with HES.
  
  
  CONCLUSIONS
  In vitro hemodilution of feline blood with RA and HES causes a small but significant impairment of whole blood coagulation, with HES leading to a significantly greater effect on coagulation than RA. Further studies are necessary to evaluate the in vivo effects and the clinical significance of these findings.
authors.affiliation: Division of Emergency and Critical Care, Laenggassstrasse 128, 3012, Bern, Switzerland.
authors.forename: Nathalie A
authors.initials: NA
authors.lastname: Albrecht
authors.affiliation: Clinical Diagnostic Laboratory, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Laenggassstrasse 124, 3012, Bern, Switzerland.
authors.forename: Judith
authors.initials: J
authors.lastname: Howard
authors.affiliation: Division of Internal Medicine/Cardiology, Small Animal Clinic, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Laenggassstrasse 128, 3012, Bern, Switzerland.
authors.forename: Alan
authors.initials: A
authors.lastname: Kovacevic
authors.affiliation: Division of Emergency and Critical Care, Laenggassstrasse 128, 3012, Bern, Switzerland. katja.adamik@vetsuisse.unib.ch.
authors.forename: Katja N
authors.initials: KN
authors.lastname: Adamik
mesh_terms: D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects*; D002415:Cats; D005260:Female; D006895:Hydroxyethyl Starch Derivatives / Q000494:pharmacology*; D066298:In Vitro Techniques; D007552:Isotonic Solutions / Q000494:pharmacology; D008297:Male; D013916:Thrombelastography / Q000662:veterinary*
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D007552:Isotonic Solutions; C028570:Ringer's acetate
keywords: Cat; Coagulation; Colloid; Hemostasis; Hydroxyethyl starch; Thromboelastometry