title: Comparison of manual and laboratory PCV and total protein using EDTA and lithium heparin canine samples.
abstract: OBJECTIVE
  To evaluate if lithium heparin (LiH) and potassium ethylenediaminetetraacetic acid (EDTA) can be used interchangeably to obtain packed cell volume (PCV) and total protein by refractometry (TPr), and to compare those values with laboratorywderived haematocrit (Hct) and total protein (TP) concentration, respectively, in canine blood samples.
  
  
  METHODS
  Blood samples taken in LiH and EDTA were manually assessed for PCV and TPr. Results were correlated to Hct and TP.
  
  
  RESULTS
  238 EDTA and corresponding serum/LiH samples were obtained. There was excellent correlation but statistically significant difference between LiH and EDTA PCV (n=43). LiH and EDTA TPr (n=43) were excellently correlated without significant difference. PCV and Hct (n=176) were excellently correlated without significant difference. LiH (n=105) and serum (n=133) TP was respectively fairly or well correlated with TPr but with significant differences. An increase in cholesterol of 1 mmol/L was associated with a mean independent increase in TPr of approximately 1 g/L.
  
  
  CONCLUSIONS
  LiH and EDTA can be used interchangeably for TPr. Although TPr and serum/plasma TP were correlated, there were statistically significant differences that could impact on clinical decision making. TPr is increased by cholesterol but this alone could not account for the magnitude of the difference observed.
authors.affiliation: University College Dublin Veterinary Hospital, School of Veterinary Medicine, University College Dublin, Dublin, Ireland.
authors.forename: A
authors.initials: A
authors.lastname: Tamborini
authors.forename: S
authors.initials: S
authors.lastname: Papakonstantinou
authors.forename: A
authors.initials: A
authors.lastname: Brown
authors.forename: S
authors.initials: S
authors.lastname: Brennan
authors.forename: R E
authors.initials: RE
authors.lastname: Shiel
authors.forename: J N
authors.initials: JN
authors.lastname: Mills
authors.forename: C T
authors.initials: CT
authors.lastname: Mooney
mesh_terms: D000818:Animals; D001738:Biuret Reaction / Q000662:veterinary; D001798:Blood Proteins / Q000032:analysis*; D004285:Dogs / Q000097:blood; D004492:Edetic Acid; D006400:Hematocrit / Q000379:methods / Q000662:veterinary*; D006493:Heparin; D008094:Lithium; D012031:Refractometry / Q000662:veterinary
chemical_list: D001798:Blood Proteins; D006493:Heparin; D008094:Lithium; D004492:Edetic Acid