Verification of the Heska Element Point-of-Care blood gas instrument for use with venous blood from alpacas and llamas, with determination of reference intervals.

BACKGROUND: The Heska Element POC ("EPOC") is a blood gas instrument intended for use with canine, feline, and equine whole blood; no verification for use with camelid specimens has been reported.

OBJECTIVES: Using camelid specimens and commercial quality control materials (QCM), we investigatee EPOC analytical performance and establish EPOC camelid reference intervals (RIs).

METHODS: Camelid blood (n = 124) was analyzed using the EPOC (pH, pCO2 , pO2 , HCO3 , base excess, SO2 , sodium, potassium, chloride, ionized calcium, TCO2 , anion gap, HCT, HGB, glucose, lactate, and creatinine); plasma was analyzed using a Roche Cobas c501 (sodium, potassium, chloride, TCO2 , anion gap, glucose, and creatinine). Method comparison data were assessed using Pearson's correlation, Passing-Bablok regression, and Bland-Altman plots. EPOC precision was evaluated using QCM and camelid blood.

RESULTS: For all measurands except anion gap, the EPOC vs Cobas instrument correlation was r > .85. Except for pO2 and pCO2 , EPOC precision (QCM and blood) ranged from a repeatability CV <1%-6.3%. Mild constant bias for chloride, glucose, TCO2 , anion gap, and creatinine, and mild proportional bias for chloride, glucose, and anion gap were present. The total error (QCM data) for the EPOC instrument was below the ASVCP-recommended allowable total error. Alpacas had higher potassium and lactate, while llamas had higher creatinine, sodium, chloride, ionized calcium, pO2 , and SO2 . Statistical RIs based on alpaca (n = 74-96) and llama data (n = 12-17) are reported descriptively.

CONCLUSIONS: The EPOC analyzer shows good performance with camelid blood. A lack of complete agreement with automated chemistry analyzers highlights the importance of interpreting patient data using instrument-specific RIs.