Evaluation of the Correlation of Arterial and Venous Lactate and Glucose Concentrations in Anesthetized Critically Ill Dogs.

OBJECTIVE: To investigate the correlation between arterial and venous concentrations of lactate and glucose and to explore the relationship between hyperlactatemia and hyperglycemia in critically ill dogs. DESIGN: Prospective clinical study. SETTING: University veterinary teaching hospital. ANIMALS: Ninety client-owned dogs presenting for emergency surgery between June 2015 and March 2024. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Arterial and venous blood samples were collected from the dorsal pedal artery and jugular vein, respectively, ≤5 min apart to measure lactate and glucose concentrations with portable devices. Dogs with known diabetes mellitus were excluded. Based on arterial blood, 35 of 90 dogs (38.9%) were hyperlactatemic, 49 (54.4%) were hyperglycemic, and 9 (10.0%) were hypoglycemic. Based on venous blood, 41 of 90 dogs (45.6%) were hyperlactatemic, 46 (51.1%) were hyperglycemic, and 8 (8.9%) were hypoglycemic. A very strong correlation was found between arterial and venous lactate and glucose concentrations (ρ = 0.850; 95% confidence interval [CI]: 0.766-0.905; p < 0.001 and ρ = 0.970; 95% CI: 0.950-0.982; p < 0.001, respectively). In dogs with arterial hyperlactatemia, a very strong correlation was found between arterial and venous samples (ρ = 0.835; 95% CI: 0.683-0.918; p < 0.001), whereas the correlation was fair in normolactatemic dogs (ρ = 0.488; 95% CI: 0.224-0.685; p < 0.001). The sensitivity and specificity of venous lactate to detect arterial hyperlactatemia were 81.8% and 88.6%, respectively. No correlation was found between arterial lactate and glucose concentrations (ρ = -0.57; 95% CI: -0.261 to -0.152; p = 0.593). CONCLUSIONS: Venous lactate and glucose concentrations correlated well with arterial values; however, hyperlactatemia was not correlated with hyperglycemia. Venous blood sampling offers a practical and reliable method for assessing lactate and glucose concentrations in critically ill dogs, reducing the need for arterial sampling in emergency situations.