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Anion Gap Calculator
The anion gap is used to distinguish between causes of metabolic acidosis. It is a measure of the unmeasured anions in serum. The gap-gap ratio is the difference between the change in anion gap and the change in bicarbonate, and is used to identify a normal anion gap metabolic acidosis or a coexisting metabolic alkalosis in the presence of a high-anion gap metabolic acidosis.
Anion Gap = Na - (HCO₃ + Cl)
Gap-Gap Ratio =
Anion Gap - 12 24-HCO₃