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Anion Gap Calculator
Calculate anion gap for metabolic acidosis assessment

About This Calculator

The anion gap helps determine the cause of metabolic acidosis by measuring unmeasured anions in blood. An elevated anion gap suggests accumulation of acids like lactate or ketones.

Formula:

Anion Gap = Na⁺ - (Cl⁻ + HCO₃⁻)

Reference Ranges:

  • • Normal: 8-12 mEq/L
  • • High anion gap: >12 mEq/L (suggests MUDPILES causes)
  • • Low anion gap: <8 mEq/L (rare)

References:

  1. 1. Emmett M, Narins RG. Clinical use of the anion gap. Medicine (Baltimore). 1977;56(1):38-54.
  2. 2. Kraut JA, Madias NE. Serum anion gap: its uses and limitations in clinical medicine. Clin J Am Soc Nephrol. 2007;2(1):162-174.
  3. 3. Berend K, et al. Diagnostic use of base excess in acid-base disorders. N Engl J Med. 2018;378(15):1419-1428.

Medical Disclaimer: This calculator is for educational purposes only. Always consult with healthcare professionals for medical decisions.

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