Point-of-care ketone meters may be used to estimate serum β-hydroxybutyrate concentrations in healthy African penguins (Spheniscus demersus)

Abstract

To evaluate the agreement between 3 point-of-care (POC) devices and a reference laboratory for measuring β-hydroxybutyrate (β-HB) concentration in African penguin (Spheniscus demersus) whole blood (WB) and plasma samples and the precision of each POC device for measuring β-HB concentration in plasma samples. 48 healthy African penguins. Blood was obtained from the right jugular vein of each penguin, and β-HB concentration was measured on each POC device using fresh WB and heparinized plasma and at the reference laboratory using plasma. β-HB concentration was measured in plasma on each POC device. All devices overestimated serum β-HB concentrations on average by 0.46 mM relative to the reference laboratory. WB samples had less error than plasma for meters A and C. Meter A had the lowest total error observed (26.4%) and the lowest mean difference (0.19 mmol/L) relative to the reference laboratory. Controlling for other factors, the magnitude of disagreement was not affected by sex, age, packed cell volume, or serum total solids concentration. WB, not plasma, should be used for measurement of β-HB concentration on the POC meters tested. Meter A showed good correlation with the reference laboratory for WB. The use of POC devices for the measurement of β-HB concentration may be acceptable when laboratory analyzers are not available. Further research is needed for clinical application and the diagnostic value of POC meters compared with reference laboratories.