This version was machine-translated from German and has not been medically reviewed. The authoritative version is the German version.
Delta gap
Anion gap minus 12 – rise in the anion gap relative to the reference value and comparison with the bicarbonate decrease
Scientific basis
Reference range of your own laboratory
Anion gap and delta ratio depend on the measurement method for sodium and chloride. The reference values used here (AG 12, HCO₃⁻ 24) are conventions of the cited papers; your own laboratory's reference range takes precedence.
Calculation aid for healthcare professionals: the calculator reproduces what the sources cited assign to the inputs. Clinical assessment and every treatment decision remain with the treating physician. Inputs and results are not stored.
Frequently asked questions
Delta gap: What does this calculator compute?
Calculates the delta gap (AG − 12) and compares it with the bicarbonate decrease (24 − HCO₃): a delta gap clearly above the bicarbonate decrease suggests an additional metabolic alkalosis, clearly below it an additional hyperchloremic acidosis (Wrenn 1990).
Delta gap: Which sources is this calculator based on?
Kraut JA, Madias NE: Serum anion gap: its uses and limitations in clinical medicine (Clin J Am Soc Nephrol 2:162–174) (2007); Figge J, Jabor A, Kazda A, Fencl V: Anion gap and hypoalbuminemia (Crit Care Med 26:1807–1810) (1998); Wrenn K: The delta (Δ) gap: an approach to mixed acid-base disorders (Ann Emerg Med 19:1310–1313) (1990); Albert MS, Dell RB, Winters RW: Quantitative displacement of acid-base equilibrium in metabolic acidosis (Ann Intern Med 66:312–322) – “Winter formula” (1967); Berend K, de Vries AP, Gans RO: Physiological approach to assessment of acid-base disturbances (N Engl J Med 371:1434–1445) – Table 2: Expected compensatory responses (2014); Kraut JA, Madias NE: Metabolic acidosis: pathophysiology, diagnosis and management (Nat Rev Nephrol 6:274–285) (2010)