Synopsis
Assess and plan an adult elective airway, optimise oxygen delivery and first-attempt success, recognise failed ventilation early, and progress without delay through the current adult rescue sequence.
- Airway assessment predicts difficulty imperfectly. Combine prior records, symptoms, examination, aspiration risk, physiology, procedure and positioning with explicit plans for ventilation, intubation, extubation and failure.
- For an unanticipated difficult adult airway, preserve oxygen delivery, call for help early, optimise each attempt, confirm ventilation with waveform capnography and move forward when a plan fails.
- The 2025 DAS sequence is Plan A tracheal intubation, Plan B second-generation supraglottic-airway ventilation, Plan C final optimised facemask ventilation and Plan D emergency front-of-neck access.
Key red flags
Previous difficult or failed facemask ventilation, supraglottic-airway use, laryngoscopy, tracheal intubation or front-of-neck access is the most consequential airway history and should trigger retrieval of the original anaesthetic record.
Stridor, voice change, dysphagia, drooling, inability to lie flat or rapidly progressive neck swelling may indicate dynamic obstruction; routine elective induction can remove the remaining airway tone and precipitate complete obstruction.
Restricted mouth opening, fixed cervical movement, upper-airway tumour, prior radiotherapy, facial trauma or marked distortion can make both primary intubation and rescue access difficult and require a preformulated specialist strategy.
A flat capnogram after attempted intubation indicates oesophageal intubation until excluded; chest movement, misting and auscultation do not replace sustained waveform capnography.
Falling saturation, absent capnographic ventilation or rapidly increasing difficulty after repeated attempts demands progression through the rescue algorithm rather than repeated use of the same unsuccessful technique.
Awake intubation, obstetric failed intubation, paediatric airway management and critically ill tracheal intubation have separate guidance; their drug, attempt and rescue details must not be imported into this planned adult pathway.
Stridor, positional dyspnoea, voice change, dysphagia, drooling, sleep-related obstruction or progressive swelling may identify a dynamic airway that could worsen when consciousness and tone are lost.
Absent or inadequate capnogram, poor chest movement, falling saturation, leak, high resistance or absent expired volume means ventilation is not confirmed and requires immediate corrective action.
Reasoning priorities
Recover direct evidence of previous mask, supraglottic, laryngoscopic, intubation and extubation performance.
A specific successful technique and the circumstances of failure are more actionable than an unsupported difficult-airway alert; unresolved prior failure warrants senior review and an alternative plan.
Worked reasoning
After elective induction in an adult, the initial optimised videolaryngoscopy attempt fails but facemask ventilation and saturation remain adequate.
- Announce the difficulty, call for help, continue facemask plus nasal oxygen, verify adequate anaesthetic depth and neuromuscular blockade, optimise position and ask the assistant to count attempts and elapsed time.
- For each further Plan A attempt, change a plausible cause of failure: improve laryngeal view or external manipulation, remove cricoid force if applied, use an introducer, change blade or device, or change to a more experienced operator.
- Stop after no more than three attempts plus one by a more experienced operator. Declare failed intubation, make the eFONA kit immediately accessible and move to Plan B rather than repeating laryngoscopy.
- Insert a second-generation supraglottic airway, limiting insertion to three attempts and confirming ventilation with waveform capnography. If ventilation succeeds, stop, think and communicate with senior input about waking, intubating through the device, proceeding without intubation, or planned surgical front-of-neck access.
- If supraglottic ventilation fails, declare failure, open the eFONA kit and move to the final optimised facemask attempt; if that does not oxygenate, declare CICO and proceed immediately to Plan D.