SurgCritCare calculator

Anion Gap

Calculate anion gap to evaluate metabolic acidosis.

Sodium mEq/LChloride mEq/LBicarbonate mEq/LAlbumin optional g/dL

Formula: AG = Na - (Cl + HCO3)
Clinical context: Elevated AG suggests unmeasured anions such as lactic acidosis, DKA, toxins, or renal failure.
Limitations: Normal range varies by institution. Albumin correction is important in many ICU patients.
Source note: Standard acid-base formula; Figge J et al. J Lab Clin Med 1991. PMID: 2045713

SurgCritCare

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SurgCritCare calculator

Calculate anion gap to evaluate metabolic acidosis.

Sodium mEq/LChloride mEq/LBicarbonate mEq/LAlbumin optional g/dL

Formula: AG = Na - (Cl + HCO3)
Clinical context: Elevated AG suggests unmeasured anions such as lactic acidosis, DKA, toxins, or renal failure.
Limitations: Normal range varies by institution. Albumin correction is important in many ICU patients.
Source note: Standard acid-base formula; Figge J et al. J Lab Clin Med 1991. PMID: 2045713