The anion gap estimates unmeasured anions in serum and helps classify metabolic acidosis. A corrected anion gap adjusts for hypoalbuminemia. The delta-delta ratio identifies mixed acid-base disorders.
Anion Gap
Corrected Anion Gap (albumin-adjusted):
Delta-Delta Ratio:
Formula
AG = Na − (Cl + HCO₃) Normal: 8–12 mEq/L Corrected AG = AG + 2.5 × (4.0 − Albumin) Delta-Ratio = (AG − 12) / (24 − HCO₃)
