Evaluation of the Element point-of-care blood gas analyzer for use in horses

Objective To compare the Element point-of-care (POC) portable blood gas analyzer with a laboratory-based bench-top reference analyzer using whole blood samples obtained from horses presenting to a referral center with various disorders in order to determine agreement between these analyzers. Design Prospective clinical study. Setting The study was conducted at a university teaching hospital at moderate altitude. Animals One hundred paired samples from 80 horses >1 year of age were collected after obtaining informed client consent. Fifty paired samples were from patients admitted for elective procedures and considered to be healthy, and 50 paired samples were emergency admissions and considered to be critically ill. Measurements and Main Results Paired whole blood samples were evaluated on both the Element POC and Radiometer ABL 800 FLEX analyzers simultaneously, and results were compared. Pearson correlation coefficients between analyzers were calculated. To assess agreement, scatter and Bland-Altman plots were evaluated, and mean difference and 95% limits of agreement were calculated for each analyte. Correlation was either good (0.8-0.92) or excellent (>0.93) for the majority of analytes. All analytes apart from hemoglobin had acceptable agreement, with >= 80% of individual results within agreement targets. Precision targets were acceptable for most analytes, with partial pressure of carbon dioxide (pCO(2)) and calcium (Ca2+) exceeding precision targets. Conclusions The portable Element POC system had acceptable agreement with the ABL 800 FLEX bench-top analyzer currently in use at the study center when evaluating the majority of analytes from equine whole blood samples.