IntroductionLactate concentrations can increase with hypoperfusion in dogs and could be used as a prognostic indicator in sick dogs. In a busy emergency service, sample evaluation could be delayed. However, sample evaluation delays have been shown to cause lactate concentration increases in healthy dogs. In sick dogs, the magnitude of increased lactate is unknown. The goal of this study was to prospectively evaluate the effect of room temperature storage times on lactate measurements in dogs presenting to an emergency service.MethodsWe evaluated the precision and accuracy of the NOVA Lactate Plus, using standard procedures. To assess the impact of time on lactate concentrations in sick dogs, we prospectively enrolled dogs presenting to an emergency service. Lactate concentrations were measured at six time points using samples stored at room temperature. A Friedman test, followed by a Wilcoxon rank test with a Bonferroni correction was used to evaluate time points.ResultsForty‐five dogs were enrolled in this prospective observational study. The Lactate Plus and table‐top analyzer compared favorably, with an R2 of .98, and a mean bias of 0.26 in 50 canine samples. Precision was acceptable, with a percent coefficient of variation of 5.39. Statistically significant increases in lactate concentrations were found at all time points over baseline (P = .008).ConclusionsIn as little as 7.5 minutes, lactate concentrations increased significantly in samples stored at room temperature. Dogs with lower initial lactate concentrations had had higher increases in lactate concentration percentages over 90 minutes.

Objective: To describe renal tubular acidosis (RTA) and secondary acquired hyperaldosteronism in a cat as an adverse effect of topiramate therapy.Case Summary: An 8-year-old neutered female cat on chronic oral topiramate therapy at a recommended dose (11.9 mg/kg q 8 h) for seizure control was presented with severe metabolic acidosis and hypokalemia. Plasma electrolyte and acid-base analysis identified a severe metabolic acidosis (pH 7.153, reference interval: 7.31-7.46), hypokalemia (2.08 mmol/L [2.08 mEq/L], reference interval: 3.5-4.8 mmol/L [3.5-4.8 mEq/L]), and ionized hypercalcemia (1.85 mmol/L [1.85 mEq/L], reference range: 1.1-1.4 mmol/L [1.1-1.4 mEq/L]). Urinalysis revealed a urine specific gravity of 1.021 and a pH of 7.0. Diagnostic workup suggested distal RTA as a cause of the cat's acid-base and electrolyte disturbances. Aldosterone concentration was moderately increased, suggestive of secondary hyperaldosteronism. The metabolic abnormalities resolved with supportive care and discontinuation of topiramate.