title: Evaluation of acid-base disorders in dogs and cats presenting to an emergency room. Part 1: comparison of three methods of acid-base analysis.
abstract: OBJECTIVE
  To compare the diagnostic performance of the traditional approach to acid-base analysis with the Stewart approach and a semiquantitative approach.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  University teaching hospital.
  
  
  METHODS
  A total number of 84 dogs and 14 cats presenting to a university teaching hospital emergency room.
  
  
  METHODS
  All dogs and cats in which venous blood samples for acid-base, lactate, and serum biochemical analysis were all collected within 60 minutes of each other, over a 5-month enrollment period. Acid-base analysis was performed using the traditional approach, Stewart approach, and a semiquantitative approach.
  
  
  RESULTS
  Traditional acid-base analysis identified respiratory acid-base abnormalities in 14/98 animals and metabolic acid-base abnormalities in 67/98. A mixed disorder of metabolic acidosis and respiratory alkalosis was most common occurring in 29/98 patients. The Stewart approach identified metabolic abnormalities in 82/98 patients; strong ion difference abnormalities were evident in 68/98 cases; an increased strong ion gap acidosis was identified in 49/98 cases; and changes in the quantity of weak acids in 25/98 cases. The semiquantitative approach identified abnormalities in all cases evaluated. Of the 14 patients with a primary respiratory acid-base abnormality, the Stewart approach identified metabolic abnormalities in 9 and the semiquantitative approach found abnormalities in all animals.
  
  
  CONCLUSIONS
  The physicochemical approaches diagnosed more acid-base abnormalities in this population than the traditional approach although many of the abnormalities identified were small and of unknown clinical relevance. The physicochemical approaches may provide greater insight as to the underlying etiology of abnormalities, which maybe of particular relevance to cases with changes in albumin and/or phosphorus concentration.
authors.affiliation: Departments of Veterinary Surgical and Radiological Sciences, School of Veterinary Medicine, University of California at Davis, Davis, CA, 95616.
authors.forename: Kate
authors.initials: K
authors.lastname: Hopper
authors.forename: Steven E
authors.initials: SE
authors.lastname: Epstein
authors.forename: Philip H
authors.initials: PH
authors.lastname: Kass
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Mellema
mesh_terms: D000137:Acid-Base Imbalance / Q000097:blood / Q000175:diagnosis / Q000662:veterinary*; D000818:Animals; D001774:Blood Chemical Analysis / Q000379:methods / Q000662:veterinary*; D002371:Cat Diseases / Q000097:blood / Q000175:diagnosis*; D002415:Cats; D004283:Dog Diseases / Q000097:blood / Q000175:diagnosis*; D004285:Dogs; D012016:Reference Values
keywords: Stewart approach; anion gap; strong ion difference