Correlation between glucose concentrations in serum, plasma, and whole blood measured by a point-of-care glucometer and serum glucose concentration measured by an automated biochemical analyzer for canine and feline blood samples.

Tauk, Barbara S; Drobatz, Kenneth J; Wallace, Koranda A; Hess, Rebecka S

OBJECTIVE To investigate the correlation between glucose concentrations in serum, plasma, and whole blood measured by a point-of-care glucometer (POCG) and serum glucose concentration measured by a biochemical analyzer. DESIGN Prospective clinical study. SAMPLES 96 blood samples from 80 dogs and 90 blood samples from 65 cats. PROCEDURES Serum, plasma, and whole blood were obtained from each blood sample. The glucose concentrations in serum, plasma, and whole blood measured by a POCG were compared with the serum glucose concentration measured by a biochemical analyzer by use of the Lin concordance correlation coefficient (ρc) and Bland-Altman plots. RESULTS For both canine and feline samples, glucose concentrations in serum and plasma measured by the POCG were more strongly correlated with the serum glucose concentration measured by the biochemical analyzer (ρc, 0.98 for both canine serum and plasma; ρc, 0.99 for both feline serum and plasma) than was that in whole blood (ρc, 0.62 for canine samples; ρc, 0.90 for feline samples). The mean difference between the glucose concentrations determined by the biochemical analyzer and the POCG in serum, plasma, and whole blood was 0.4, 0.3, and 31 mg/dL, respectively, for canine samples and 7, 6, and 32 mg/dL, respectively, for feline samples. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that use of a POCG to measure glucose concentrations in serum or plasma may increase the accuracy and reliability of diagnostic and treatment decisions associated with glucose homeostasis disorders in dogs and cats.