Intubation Difficulty Scale (IDS)

Intubation Difficulty Scale (Adnet 1997): sums N1-N7 (extra attempts, extra operators, alternative techniques, Cormack-Lehane grade - 1, lifting force, laryngeal pressure, cord adduction).

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Attempts beyond the first
1
Operators beyond the first
0
Alternative techniques used
0
Cormack-Lehane grade
2

Result: Intubation Difficulty Scale 2 — slight-to-moderate difficulty (1-5).

The tool opens with these values already filled in. Replace them with your own.

What the result means

0
Easy intubation.
1-5
Slight-to-moderate difficulty.
> 5
Difficult intubation (N1-N7 summed). A complexity score, not a diagnosis.

What you enter

  • Attempts beyond the first (N1)
  • Operators beyond the first (N2)
  • Alternative techniques used (N3)
  • Cormack-Lehane grade (N4 = grade - 1)
  • Increased lifting force required (N5)
  • External laryngeal pressure applied (N6)
  • Vocal cords adducted / closed (N7)
How this is calculated

Adnet F, Borron SW, Racine SX, et al. The intubation difficulty scale (IDS): proposal and evaluation of a new score. Anesthesiology. 1997;87(6):1290-1297. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.