Assessment of five portable blood glucose meters for use in cats

OBJECTIVE: To evaluate the clinical and analytic accuracy of 5 portable blood glucose meters (PBGM) in cats, with emphasis on the detection of potential sources of error. ANIMALS: 200 cats. PROCEDURE: Venous blood glucose readings from 5 PBGM were compared with the results of a hexokinase reference method. Agreement among methods was determined by error grid analysis and statistical methods. RESULTS: A total of 2,975 PBGM readings and 513 reference values were analyzed. The accuracy of the PBGM varied in different glycemic ranges. The largest differences between PBGM readings and reference values were in the high glycemic range; 4 PBGM underestimated and 1 PBGM overestimated the reference values in most instances. In the low and reference glycemic ranges, the absolute differences between PBGM readings and reference values were small. Despite the analytic differences in accuracy, 4 PBGM had 100% and 1 PBGM had 98.7% of readings in the clinically acceptable values of the error grid analysis. Within- and between-day precisions were good for all PBGM. Significant differences were not detected between readings of EDTA and lithium-heparinized blood and fresh blood without anticoagulant. Compared with these blood types, 1 PBGM had significantly different readings with fluoride anticoagulated blood. In blood samples with a low Hct, all PBGM overestimated glucose concentrations. Sample volumes < 3 microl resulted in inaccurate measurements in 3 PBGM. CONCLUSIONS AND CLINICAL RELEVANCE: Performance varied among the 5 PBGM analyzed; however, all PBGM were deemed acceptable for clinical use in cats.