Step 1 of 6
Recognition, Severity Grading & Team Activation
Grade the airway threat (1–5) and activate the multidisciplinary airway team before any examination.
The first decision in every patient with suspected acute airway
obstruction is severity grading. The bespoke
threat_grade_matrix collates the five-grade scheme — Grade 1
(mild stridor, stable saturation) through Grade 5 (respiratory
arrest) — and the immediate action each grade demands.
Grade ≥3 mandates activation of the multidisciplinary airway
team — otolaryngology, anaesthesia, intensive care, emergency
medicine, and (where applicable) thoracic surgery and ECMO. The
team operates under Crisis Resource Management principles
(see framework_crm_airway): a named leader, closed-loop
communication, verbalised backup plans, and explicit declaration
of "difficult airway" or "CICO" the moment criteria are met.
Avoid the cognitive trap of grading by what the patient looks like at a single instant. The same patient at Grade 2 thirty minutes ago is at Grade 4 now if exhaustion has set in; trends matter as much as static signs.
- Grade 1–5 severity classification
- Activate multidisciplinary airway team at Grade ≥3
- Crisis Resource Management — leader, intubator, surgical operator, medication, monitoring nurse
- Closed-loop communication; explicit declaration of "difficult airway" / "CICO"
- Recognise exhaustion + falling effort = critical, not improving
Key statistics
Critical-narrowing physiology
1 mm = major resistance rise
Airway resistance scales as the fourth power of radius (Poiseuille); one millimetre of subglottic oedema can halve cross-sectional area in an adult.
★ High-yield pearls (chapter-wide)
- Oxygenation is more important than intubation — secure SpO₂ first, definitive airway second.
- Preserve spontaneous ventilation whenever possible; paralysis converts a difficult airway into a CICO crisis.
- The first airway attempt is the best attempt — optimise position, preoxygenation, operator, equipment, and team before the first laryngoscopy.
- Call for help early; do not wait until you are committed and failing.
- Do not paralyse an uncertain airway — awake fibreoptic intubation is the safe path when difficulty is predicted.
- Failed airway = surgical airway. Declare CICO and proceed to front-of-neck access without further laryngoscopic attempts.
- Extubation is also an airway procedure — plan it with the same rigour as intubation.
- Never transport an unstable airway unnecessarily; secure it where you stand.
- Children deteriorate rapidly; for paediatric stridor see the dedicated chapter rather than extrapolating from adult algorithms.
- Airway algorithms must adapt dynamically to pathology and physiology — the right next step in a mediastinal mass is the wrong next step in angioedema.
Evidence base
1 source- HIGH
Apfelbaum JL et al. · Anesthesiology · 2022Practice guidelinePMID 34762729
ASA 2022 practice guidelines for management of the difficult airway — current anchor for predicted difficult airway, controlled airway pathway, and CICO escalation. Vol 136(1):31-81.
Decision tree
The first gate is severity (Grade 1–5). Grade 4–5 mobilises the difficult-airway trolley and surgical operator; CICO criteria (cannot oxygenate AND cannot ventilate) trigger emergency front-of-neck access. For stable Grade 1–3, an etiology trigger routes to one of 8 management pathways.