Accuracy of a Portable Blood Gas Analyzer Incorporating Optodes for Canine Blood

Abstract

The accuracy of a portable blood gas analyzer (OPTI 1) was evaluated using canine blood and aqueous control solutions. Sixty‐four arterial blood samples were collected from 11 anesthetized dogs and were analyzed for pH, partial pressure of carbon dioxide (Pco2), partial pressure of oxygen (Po2), and bicarbonate concentration ([HCO3‐]) values by the OPTI 1 and a conventional blood gas analyzer (GASTAT 3). The conventional analyzer was considered as a standard against which the OPTI 1 was evaluated. Comparison of OPTI 1 results with those of GASTAT 3 by linear regression analysis revealed a high degree of correlation with the GASTAT 3 (r= .90‐.91). The mean ± SD of the differences between OPTI 1 and GASTAT 3 values was ‐0.008 ± 0.017 for pH, ‐0.88 ± 3.33 mm Hg for Pco2, 3.71 ± 6.98 mm Hg for Po2, and ‐0.34 ± 1.45 mEq/L for [HCO3‐]. No statistically significant difference was found between the OPTI 1 and the GASTAT 3. Agreement between these 2 methods is within clinically acceptable ranges for pH, Pco2, Po2, and [HCO3‐]. The coefficients of variation for measured pH, Pco2, and Po2 values of 3 aqueous control solutions (acidic, normal, and alkalotic) analyzed by the OPTI 1 ranged from 0.047 to 0.072% for pH, 0.78 to 1.81% for Pco2, and 0.73 to 2.77% for Po2. The OPTI 1 is concluded to provide canine blood gas analysis with an accuracy that is comparable with that of conventional benchtop blood gas analyzers.