Cuff Leak Test
Computes the cuff leak volume before extubation and reports it against both cutoffs in common use.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Inspired tidal volume with the cuff up, mL
- 500 mL
- Averaged expired volume with the cuff down, mL
- 450 mL
Result: a leak of 50 mL, 10 percent, small by both cutoffs
The tool opens with these values already filled in. Replace them with your own.
What the result means
- The measurement
- The inspired tidal volume minus the averaged expired volume with the cuff down. Averaged over several breaths, not taken from one.
- The two cutoffs
- An absolute leak under 110 mL, or a leak under 10 to 15 percent of the inspired volume. The guideline does not fix one, so both are reported.
- Who to test
- Only patients at high risk of post-extubation stridor. Performed on everybody the test delays extubations that did not need delaying.
- A failed test
- Not an instruction to keep the tube in. For a patient who fails and is otherwise ready, systemic steroids at least 4 hours before extubation are suggested.
- Predictive value
- Poor in the positive direction. A small leak raises the probability of stridor without establishing it, and a normal leak does not exclude it.
- What moves it
- Secretions, tube size and patient effort. A single discordant breath is not a result.
What you enter
- Inspired tidal volume with the cuff up, mL
- Averaged expired volume with the cuff down, mL
- At high risk of post-extubation stridor (the group the guideline recommends testing)
How this is calculated
Girard TD, Alhazzani W, Kress JP, et al. An Official ATS/ACCP Clinical Practice Guideline: Liberation from Mechanical Ventilation in Critically Ill Adults. Am J Respir Crit Care Med. 2017;195(1):120-133. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.