Indications
- Airway protection — reduced consciousness with loss of protective reflexes, high aspiration risk, or an unstable/threatened airway (burns, angioedema, expanding neck haematoma).
- Ventilatory failure — inability to maintain oxygenation or ventilation despite maximal non-invasive support.
- Anticipated clinical course — for transfer, imaging, or a deteriorating trajectory (e.g. worsening sepsis, major trauma, status epilepticus) where the airway is likely to be lost.
- Combative or agitated patient preventing safe assessment or life-saving treatment (RSI for behavioural indication is high-risk and should involve senior/consultant sign-off).
Contraindications & cautions
Absolute
- None if the airway genuinely cannot be protected or oxygenation cannot be achieved by other means — RSI may still be the safest option even when predicted difficult, provided a failed-airway plan is rehearsed first.
Cautions requiring senior input
- Predicted difficult laryngoscopy, difficult bag-mask ventilation, or difficult front-of-neck access (short neck, radiotherapy, obesity, beard, C-spine immobilisation).
- Haemodynamic instability — induction agents and positive-pressure ventilation both drop preload and cardiac output; have vasopressor ready.
- Severe bronchospasm or raised intracranial pressure — drug choice and induction sequence should be tailored with senior input.
Preparation & checklist culture
- Use a structured RSI checklist read aloud by a second clinician before every attempt — most ED and prehospital RSI protocols in the UK are built around a shared checklist culture, following the same crisis-resource-management principles as the DAS guidelines.
- SOAPME-style preparation: Suction (on, under the pillow, ready), Oxygen (preoxygenation and apnoeic oxygenation devices ready), Airway equipment (two laryngoscopes, sizes of tube, bougie, supraglottic device, surgical airway kit opened and visible), Positioning, Monitoring (capnography running before induction), End-tidal CO2/drugs drawn up and labelled.
- Team brief: roles assigned (team leader, drug giver, airway operator, cricoid/manual in-line stabilisation if needed, documenter); shared mental model of Plan A–D and who does what if Plan A fails.
- IV/IO access secured and working; full monitoring (ECG, SpO2, non-invasive blood pressure cycling frequently, capnography); vasopressor drawn up and immediately available.
- Optimise physiology before pushing drugs where possible — fluid bolus for hypotension, correct hypoxia, treat reversible causes; "resuscitate before you intubate."
Equipment
Drugs
Choice and dose are individualised to physiology, and must follow your local RSI drug protocol — figures below are typical adult ranges used in UK emergency and prehospital practice; always confirm against your department's own guideline before use.
Induction agents
- Ketamine ~1–2 mg/kg IV — favoured in haemodynamic instability, bronchospasm and where cardiovascular stability is a priority.
- Propofol ~1.5–2.5 mg/kg IV, reduced substantially in shock/older patients — favoured when blunting the pressor response or airway reflexes is prioritised, but causes vasodilation and myocardial depression.
- Reduce induction dose (and use small titrated boluses) in shock, sepsis and the elderly — "resuscitate before you intubate" rather than compensating with a bigger dose.
Neuromuscular blockade
- Rocuronium 1.0–1.2 mg/kg IV — at the higher end of this range, onset and intubating conditions are comparable to suxamethonium (many UK services use 1.0 mg/kg first line); longer duration of action — have sugammadex available if a rescue reversal plan requires it.
- Suxamethonium ~1–1.5 mg/kg IV — rapid onset and offset; caution in hyperkalaemia, neuromuscular disease, and burns/major trauma beyond the acute phase.
Positioning & preoxygenation
Position
Ramp the patient (ear-to-sternal-notch alignment) unless C-spine precautions dictate neutral positioning; head-up/reverse Trendelenburg improves apnoea tolerance and reduces aspiration risk where not contraindicated.
Preoxygenate
High-flow oxygen via a tight-fitting mask (or non-invasive ventilation/PEEP-valve bagging in shunt physiology) for several minutes, aiming to denitrogenate and maximise the oxygen reservoir before apnoea.
Apnoeic oxygenation
Add nasal cannulae at flow tolerated by the patient, left running through preoxygenation and continued through the apnoeic phase and laryngoscopy — extends safe apnoea time.
Cricoid pressure
Use per local protocol; if applied and it worsens the laryngoscopic view, release or adjust it — a good view takes priority.
Laryngoscopy & first-pass strategy
First look with the best available tools
DAS 2025 recommends videolaryngoscopy as first-line where available — it improves glottic view and first-attempt success. Have suction immediately to hand for airway soiling.
Load an adjunct for the first attempt
DAS 2025 advises using an adjunct — stylet, bougie or flexible bronchoscope — with a hyperangulated videolaryngoscope blade, where tube delivery rather than glottic view is the limiting step; a rigid stylet is often the more practical choice with that geometry. With Macintosh-style direct or video laryngoscopy the choice of bougie versus stylet is operator preference: the multicentre BOUGIE trial found no difference in first-attempt success, so a routine bougie-first policy is reasonable but is not superior and is not mandated. The bougie earns its place in a restricted view (grade 2b–3), C-spine immobilisation or a soiled airway — pass the coudé tip anteriorly under the epiglottis, feel for tracheal "clicks"/hold-up, then railroad the tube. Weigh any adjunct against the small risk of airway trauma.
Limit attempts
Declare difficulty early. DAS 2025 sets a limit of three attempts, plus one further attempt by a more experienced operator (3+1), before moving to Plan B — change something meaningful between attempts (position, device, operator, blade), not just repeating the same technique.
Call for help early
Escalate to the most experienced airway operator available in the department, and to anaesthetics/ICU, as soon as any difficulty is anticipated or encountered — do not wait until Plan A has already failed.
Tube confirmation
- Look for a persistent, sustained square-wave capnography trace over several breaths, alongside chest rise, bilateral air entry, and misting in the tube.
- If any doubt exists about tube position at any time — re-confirm immediately; a lost or displaced airway is a leading cause of preventable death in airway registries.
- Secure the tube, note the length at the teeth/lips, and obtain a chest X-ray to check tube tip position once stabilised.
Failed intubation drill — DAS 2025 Plans A–D
- Plan A fails (after limited attempts, oxygenating throughout) → declare failed intubation out loud, insert a supraglottic airway device (Plan B).
- Plan B fails (up to three SAD attempts) → final facemask ventilation attempt (Plan C); if oxygenation succeeds, wake the patient if possible or maintain oxygenation and get senior help.
- Plan C fails with a paralysed, unoxygenatable patient (CICO — can't intubate, can't oxygenate) → proceed immediately to emergency front-of-neck airway (Plan D): scalpel cricothyroidotomy, the DAS-recommended rescue technique, using the scalpel-bougie-tube method.
Human factors
- Verbalise the plan and the failure pathway out loud before the first drug is given — everyone in the room should know Plan A–D and their own role.
- Declare difficulty and escalate early rather than silently persisting — this is one of the most consistently repeated safety lessons from national airway incident reports.
- Nominate a single team leader who is not the airway operator wherever staffing allows, to maintain situational awareness.
- Debrief after every RSI, especially a difficult one — capture what worked and what to change next time.
DOPS pointers
RCEM curriculum: Intermediate/Higher Procedural Skill. What assessors look for at each entrustment level:
| 1 | Observed only — can describe indications, drugs, and the Plan A–D algorithm. |
| 2a | Performs with a senior scrubbed/present throughout: correct preparation, checklist use, preoxygenation, first-pass technique. |
| 2b | Performs with senior in the department: manages routine RSI including drug selection and dose adjustment for physiology. |
| 3 | Indirect supervision: recognises and manages a difficult airway, moves through Plan A–D appropriately, leads the team. |
| 4 | Independent; supervises and teaches others, leads departmental airway safety and debrief culture. |
References
- Ahmad I, El-Boghdadly K, Ahmed A, et al. Difficult Airway Society 2025 guidelines for management of unanticipated difficult tracheal intubation in adults. Br J Anaesth 2026;136(2):283–307.
- Driver BE, Semler MW, Self WH, et al. Effect of use of a bougie vs endotracheal tube with stylet on successful intubation on the first attempt among critically ill patients (BOUGIE randomised clinical trial). JAMA 2021;326(24):2488–2497.
- Higgs A, McGrath BA, Goddard C, et al. Guidelines for the management of tracheal intubation in critically ill adults. Br J Anaesth 2018;120(2):323–352.
- RCEM Curriculum 2021 — Emergency Medicine Specialty Learning Outcomes: intermediate/higher procedural skills (DOPS), airway management.
- RCEMLearning — Rapid Sequence Induction and airway management resources.