Comparison of canine capillary and jugular venous blood lactate concentrations determined by use of an enzymatic-amperometric bedside system

Abstract

To evaluate the analytical agreement between blood lactate concentrations determined by use of an enzymatic-amperometric bedside system in capillary blood samples from the pinna and in jugular venous blood samples from dogs. 53 dogs. For each dog, venous and capillary blood samples were obtained from a jugular vein and from the ear pinna (by use of a lancing device), respectively, following a randomized sequence of collection. Lactate concentrations in both types of samples were analyzed by use of an enzymatic-amperometric bedside system intended for lactate detection in capillary blood samples from humans that was previously validated in dogs. The Passing-Bablock regression analysis was used to compare venous and capillary blood lactate concentrations; the level of agreement was calculated by use of the Bland-Altman method. Jugular venous blood samples were collected without difficulty from all 53 dogs. A capillary blood sample was obtained from only 47 dogs. The correlation coefficient between lactate concentrations measured in venous and capillary blood samples was 0.58 (slope, 2.0 [95% confidence interval, 1.5 to 3.0]; intercept, -1.2 [95% confidence interval, -3.1 to 0.4]). The mean difference between methods was 0.72 mmol/L (95% confidence interval, 0.38 to 1.06) with limits of agreement of -1.55 to 2.99 mmol/L. Because of the lack of agreement between lactate concentrations determined in capillary and jugular venous blood samples, measurement of capillary blood lactate concentration in dogs performed with the technique used in the study does not appear to be a reliable alternative to jugular venous blood measurements.