title: Comparison of jugular and transverse facial venous sinus blood analytes in healthy and critically ill adult horses.
abstract: OBJECTIVE
  To compare blood gas, electrolyte, and metabolic analysis results between blood obtained by jugular and transverse facial venous sinus (TFVS) venipuncture in healthy adult horses and sick adult horses presented for emergency evaluation.
  
  
  METHODS
  Prospective, experimental study, from June 2012 to October 2013.
  
  
  METHODS
  Large animal university teaching hospital.
  
  
  METHODS
  Ten healthy adult University-owned horses and 48 client-owned adult horses (≥2 years old) presenting to the large animal hospital emergency service for medical or surgical evaluation of systemic illness.
  
  
  METHODS
  Venipunctures (jugular vein [JV] and TFVS) were performed using preheparinized syringes and obtained prior to institution of medical therapy. Samples were analyzed in random order within a 10-minute interval using a point-of-care blood gas analyzer (NOVA Critical Care Xpress) that also reports electrolyte and metabolite results. Comparisons between venipuncture sites were analyzed using the Student's paired t-test for normally distributed data and the Wilcoxon paired test for nonnormally distributed data. Bland-Altman analysis was used to assess agreement between venipuncture sites.
  
  
  RESULTS
  There were no statistically significant differences found between variables for JV and TFVS in healthy horses. In sick horses, JV measurements were greater than TFVS for ionized calcium (P = 0.002) and glucose (P = 0.001), and less than TFVS for hematocrit (P = 0.015). Bland-Altman plots demonstrated small biases but overall agreement between sites.
  
  
  CONCLUSIONS
  The TFVS can be used interchangeably with JV for venous blood gas analysis in healthy horses. In sick horses, identified differences were small and likely not clinically important. The reliability of this point-of-care blood gas analyzer for measurement of hematocrit remains to be determined.
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, IL, 61802.
authors.forename: Kara M
authors.initials: KM
authors.lastname: Lascola
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, IL, 61802.
authors.forename: Karie
authors.initials: K
authors.lastname: Vander Werf
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, IL, 61802.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Freese
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, IL, 61802.
authors.forename: Alison
authors.initials: A
authors.lastname: Morgera
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, IL, 61802.
authors.forename: David J
authors.initials: DJ
authors.lastname: Schaeffer
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, IL, 61802.
authors.forename: Pamela
authors.initials: P
authors.lastname: Wilkins
mesh_terms: D000818:Animals; D001784:Blood Gas Analysis / Q000662:veterinary; D001800:Blood Specimen Collection / Q000662:veterinary*; D016022:Case-Control Studies; D003422:Critical Care; D016638:Critical Illness; D004573:Electrolytes / Q000097:blood; D004636:Emergency Service, Hospital; D006400:Hematocrit / Q000662:veterinary; D006734:Horse Diseases / Q000097:blood*; D006736:Horses; D007601:Jugular Veins; D019095:Point-of-Care Systems; D011446:Prospective Studies; D015203:Reproducibility of Results
chemical_list: D004573:Electrolytes
keywords: blood gas; electrolyte; equine; lactate