title: Comparison of pH, lactate, and glucose analysis of equine synovial fluid using a portable clinical analyzer with a bench-top blood gas analyzer.
abstract: OBJECTIVE
  To compare agreement between a portable clinical analyzer and laboratory-based bench-top analyzer for analysis of pH, lactate, and glucose concentrations in synovial fluid.
  
  
  METHODS
  Prospective experimental study.
  
  
  METHODS
  Clinically normal horses (n=8); 6 horses euthanatized for reasons unrelated to the study; 11 horses that had synoviocentesis for reasons other than sepsis; 7 horses that had synoviocentesis for evaluation of sepsis; and 2 horses without recorded clinical data. Median age of horses was 8 years (range, 1 day to 24 years).
  
  
  METHODS
  Supernatant from each synovial fluid sample was analyzed for pH, lactate, and glucose concentrations using an ABL 705 laboratory-based bench-top analyzer and i-STAT portable clinical analyzer. Bland-Altman plots were constructed and concordance analysis performed to determine bias and agreement between the 2 analyzers.
  
  
  RESULTS
  There was acceptable agreement between analyzers for lactate and glucose concentrations, with biases of 0.198 mmol/L and 9 mg/dL and concordance correlation coefficients of 0.97 and 0.96 for lactate and glucose, respectively. The agreement between analyzers for pH was not acceptable, with a bias of -0.057 and concordance correlation coefficient of 0.89.
  
  
  CONCLUSIONS
  This study found that the portable clinical analyzer performed similarly to the bench-top blood gas analyzer for evaluation of lactate and glucose concentrations, but not pH, in synovial fluid.
authors.affiliation: Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, CA 95616, USA. jedechant@ucdavis.edu
authors.forename: Julie E
authors.initials: JE
authors.lastname: Dechant
authors.forename: William A
authors.initials: WA
authors.lastname: Symm
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Nieto
mesh_terms: D000818:Animals; D001424:Bacterial Infections / Q000175:diagnosis / Q000378:metabolism / Q000662:veterinary*; D001784:Blood Gas Analysis / Q000295:instrumentation / Q000662:veterinary*; D005947:Glucose / Q000032:analysis*; D006734:Horse Diseases / Q000378:metabolism*; D006736:Horses; D006863:Hydrogen-Ion Concentration; D007592:Joint Diseases / Q000175:diagnosis / Q000662:veterinary*; D019344:Lactic Acid / Q000032:analysis*; D013582:Synovial Fluid / Q000737:chemistry*
chemical_list: D019344:Lactic Acid; D005947:Glucose