The effect of sodium bicarbonate and validation of beckman coulter AU680 analyzers for measuring total carbon dioxide (TCO 2 ) concentrations in horse serum.

This study evaluated the usage of Beckman Coulter AU680 analyzers for measurement of TCO2 in horse serum, and the effect of sodium bicarbonate administrations on serum TCO2 levels in resting horses. Treatment of horses with sodium bicarbonate did not result in any adverse events. Mean TCO2 concentration was significantly higher from 1 to 8 h in the sodium bicarbonate-treated horses compared to the untreated controls. Within an hour, administration of sodium bicarbonate increased the TCO2 level from 31.5 ± -2.5 (SD) to 34.0 ± 2.65 (SD) mmol/L and at 2-8 h post-administration, the TCO2 level was above the 36 mmol/L cut-off level. In all quality control analysis of Australian standard by Beckman Coulter AU680 analyzer, the instrument slightly over estimated the TCO2 level but the values were in close agreement with mean TCO2 level being 38.03 with ± 0.87 mmol/L (SD). Expanded uncertainty was calculated using different levels of confidence interval. Based on 99.5% confidence interval using 0.805% expanded uncertainty using mean measured concentration of 38.05 mmol/L, it was estimated that any race samples TCO2 level higher than 38.5 mmol/L will be indicative of sodium bicarbonate administration using Beckman Coulter AU680 analyzer in Louisiana.