“The base excess is another surrogate marker of metabolic acidosis or alkalosis.
- A high base excess (> +2mmol/L) indicates that there is a higher than normal amount of HCO3- in the blood, which may be due to a primary metabolic alkalosis or a compensated respiratory acidosis.
- A low base excess (< -2mmol/L) indicates that there is a lower than normal amount of HCO3- in the blood, suggesting either a primary metabolic acidosis or a compensated respiratory alkalosis.”
Source: https://geekymedics.com/abg-interpretation