High anion gap metabolic acidosis critical pathways

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Approach

Anion gap

Delta-delta (ΔΔ) value

Definition

Delta-Delta value is used to determine whether there is an additional metabolic acid-base disturbance or not.
Delta-Delta (ΔΔ) = Delta anion gap (ΔAG) / Delta bicarbonate (ΔHCO3)
- Delta anion gap (ΔAG) = Calculated anion gap – Expected anion gap
  - Calculated anion gap = [Na⁺] – [Cl^–] – [HCO₃^–]
  - Expected anion gap = 2.5 x serum albumin level
- Delta bicarbonate (ΔHCO₃) = 24 – serum bicarbonate level

References

Approach