Delta Ratio

The Delta Ratio is a formula that can be used to assess elevated anion gap metabolic acidosis and to evaluate whether a mixed acid base disorder (metabolic acidosis) is present. The anion gap (AG) is calculated first and if an anion gap is present, results in either a HAGMA high anion gap metabolic acidosis or a NAGMA normal anion gap acidosis. Occasionally there will be a low anion gap but this is usually an oddity of measurement rather than a clinical concern [see anion gap for an explanation of low anion gap metabolic acidosis].