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Difficult Airway Algorithm

Source: ASA Practice Guidelines for Management of the Difficult Airway 2022 · Last reviewed: Jul 2026

1
Assessment

Screen for predictors of difficult intubation & difficult ventilation (bag-mask/supraglottic), aspiration risk, rapid desaturation risk, and difficult emergency airway access.

2
Decision

Choose strategy: awake intubation, or intubation after general anaesthesia induction?

Consider Awake Intubation when...

3a
  • Anticipated difficult ventilation
  • Increased aspiration risk
  • Cannot tolerate brief apnoea
  • Predicted difficult emergency/invasive airway access

Intubation After Induction (low risk)

3b

If ventilation is adequate but intubation fails: limit attempts, combine techniques (video-laryngoscopy + flexible bronchoscopy), or wake the patient if non-emergent.

Principles Throughout

Optimise oxygenationLimit laryngoscopy attemptsCall for help earlyConfirm tube with capnography
4
Critical Decision

Can you ventilate?

Yes, ventilation adequate but intubation failed → continue limited attempts/alternative techniques, or postpone & wake the patient if possible.

No — CICO (Can't Ventilate, Can't Oxygenate) → immediate invasive airway (cricothyroidotomy/front-of-neck access), do not delay.

Key principle: the true failure is not needing an invasive airway — it is being late in performing it. Not a substitute for airway-management training.