Evaluation of the Lactate Plus monitor for plasma lactate concentration measurement in dogs.

OBJECTIVE: To compare the Lactate Plus handheld monitor to a reference blood gas analyzer for determining plasma lactate concentrations in canine whole blood.

DESIGN: Prospective observational study.

SETTING: University teaching hospital.

ANIMALS: Ninety-four dogs hospitalized or admitted through the emergency service provided 125 blood samples. Only dogs that required a venous or arterial blood gas evaluation as a part of their diagnostic assessment or ongoing management were included.

INTERVENTIONS: None.

MEASUREMENTS AND MAIN RESULTS: Canine whole blood samples were assayed for plasma lactate concentration with a reference blood gas analyzer and the Lactate Plus monitor. Correlation and Bland-Altman analyses were used to compare results between the 2 methods. A subset of blood samples was repeatedly analyzed with the Lactate Plus to assess monitor precision. Plasma lactate measurements from the Lactate Plus monitor showed excellent correlation with those from the reference analyzer (ρ = 0.98, P < 0.0001). Bland-Altman analysis revealed a small bias (0.1296). Agreement between the 2 methods was less consistent for lactate concentrations >5 mmol/L. The coefficient of variation ranged from 0-26.2% (median, 3.7%) and was <15% for 50/53 samples.

CONCLUSIONS: The Lactate Plus provides a fast and affordable method to measure plasma lactate concentration in dogs. Results showed excellent agreement with the reference analyzer and precision of the instrument was acceptable.