Comparison of point-of-care NOVA CCX blood gas analyzer to laboratory analyzer in a population of healthy adult cats

Objective: To compare the level of agreement of measurement of analytes (sodium, chloride, potassium, urea nitrogen [UN], creatinine, glucose) in a population of healthy adult cats between the point-of-care (POC) analyzer and laboratory analyzer. To establish reference intervals for the POC analyzer in healthy adult cats. Design: Prospective observational study. Setting: University teaching hospital. Animals: Fifty-five cats were screened. Seven cats were excluded due to aggression that prohibited phlebotomy, and 1 cat was excluded due to prolonged restraint; 47 cats were enrolled. Interventions: None. Measurements and Main Results: In this patient population, reference intervals for the POC analyzer were calculated: sodium 145–157 mmol/L; chloride 116–124 mmol/L; potassium 3.4–5.5 mmol/L; UN 5.71–13.9 mmol/L (16–39 mg/dl); creatinine 74.3–189.2 mmol/L (0.84–2.14 mg/dl); and glucose 4–11.8 mmol/L (72–213 mg/dl). Comparison between the POC analyzer and laboratory analyzer using the Bland–Altman method was performed. The bias for each analyte is as follows: sodium 1.55 mmol/L; chloride 0.99 mmol/L; potassium 0.21 mmol/L; UN –0.25 mmol/L (–0.7 mg/dl); creatinine 9.73 mmol/L (0.11 mg/dl); and glucose 0.5 mmol/L (9.79 mg/dl). Conclusions: Reference intervals for each analyte were similar to other chemistry analyzers. There was no significant difference between the POC and laboratory analyzers in analysis of UN, with a statistically significant difference observed with sodium, potassium, chloride, creatinine, and glucose. However, the values are likely not sufficiently different to alter initial clinical decisions regarding patient care.