Mixed disorder screening for high anion gap metabolic acidosis
Delta Gap Calculator for Mixed Acid-Base Disorders
Calculate the delta gap to help determine whether a patient with a high anion gap metabolic acidosis may also have a second metabolic disorder. This is one of the fastest bedside tools for screening for mixed acid-base disorders.
Use this alongside our Anion Gap Calculator, Winter's Formula tool, Mixed Acid-Base Disorders guide, and our Anion Gap guide for a more complete acid-base interpretation workflow.
Calculator inputs
What the delta gap helps you detect
Low delta gap
Suggests the bicarbonate has fallen more than expected, which can support a second normal anion gap metabolic acidosis.
High delta gap
Suggests the bicarbonate has not fallen as much as expected, which can support a concurrent metabolic alkalosis or chronic respiratory process.
Results
How to think about the delta gap
The delta gap is most useful when you already know the patient has a high anion gap metabolic acidosis. It helps answer the next question: is that the only metabolic process going on, or is there another acid-base disorder layered on top?
This is why delta gap is often paired with the anion gap, Winter's formula, and the full ABG interpretation workflow rather than used alone.
How this fits into the PulmTools acid-base cluster
- • Start with the anion gap to identify a high gap process
- • Use Winter's Formula to assess respiratory compensation
- • Use Mixed Acid-Base Disorders for the broader framework
- • Review the Delta Gap guide for examples and bedside pattern recognition
- • Use the ABG Analyzer to tie the whole picture together