Three failed attempts at laryngoscopy and your patient’s oxygen saturation drops to 85%. You know the next move matters, but the pressure makes clear thinking difficult. Multiple intubation attempts increase the risk of trauma, aspiration, hypoxia, and cardiac arrest. NAP4 data showed that 74% of airway-related deaths in the ICU involved failure to follow an algorithm or call for help early enough.
Evidence-based algorithms from the Difficult Airway Society (DAS) and American Society of Anesthesiologists (ASA) give you a structured path through failed intubation. These protocols set strict limits on attempts, define clear decision points, and guide your team through Plans A to D before hypoxia causes irreversible harm.
This guide breaks down the failed intubation algorithm into actionable steps. You’ll learn when to declare failure, how to optimise each attempt, which cognitive aids prevent fixation errors, and where to find printable checklists for your emergency trolley. We’ll cover obstetric variants and explain why pre-intubation planning matters as much as the algorithm itself.
Why a failed intubation algorithm matters
You face a paradox during difficult airway management. The more attempts you make at laryngoscopy, the harder successful intubation becomes. Each failed attempt causes airway oedema, bleeding, and distorted anatomy, turning a difficult airway into an impossible one. Mort’s 2004 study of 2,833 emergency intubations showed that when attempts exceeded two, hypoxaemia occurred in 70% of patients compared to just 11.8% after two or fewer attempts. Aspiration rates jumped from 0.8% to 13%, and cardiac arrest from 0.7% to 11%.
The fixation trap
Your brain defaults to what you know under stress. This cognitive fixation explains why experienced operators repeat the same failing technique instead of moving to alternative strategies. NAP4 investigators found multiple cases where teams performed five, six, or even seven laryngoscopy attempts while the patient deteriorated. The failed intubation algorithm breaks this pattern by setting strict attempt limits and forcing you to escalate before hypoxia causes permanent harm.
"An analysis of 2833 tracheal intubations in the ICU and ED showed that, when there were more than two attempts at laryngoscopy, the incidence of several harmful complications rose markedly."
Without a structured approach, you’re also more likely to skip critical steps. NAP4 data revealed that 74% of intensive care deaths involved failure to use capnography, declare difficulty early, or perform timely surgical airways. Teams knew what to do but didn’t do it because stress overrode their training. A failed intubation algorithm gives your team a shared mental model that overrides panic and guides every member through escalating Plans A to D.
Step 1. Prime the team and the plan
Your failed intubation algorithm begins before you touch the laryngoscope. Teams that verbalise Plans A through D before induction reduce the chance of cognitive fixation when difficulty occurs. The 2015 DAS guidelines and NAP4 recommendations both emphasise pre-intubation briefing as the single most effective way to prevent airway disasters. You need every team member to know what happens if Plan A fails, who calls for help, and where the surgical airway kit sits.
Brief the team on Plans A to D
Walk through your strategy aloud while your team listens. State your primary intubation technique (Plan A), the maximum number of attempts you’ll allow (typically three), and what triggers escalation to Plan B. Your team needs to hear Plan C (face mask or supraglottic airway oxygenation) and Plan D (surgical airway) spoken out loud, even if you expect a straightforward intubation. This verbal commitment overrides the fixation reflex that makes operators repeat failing techniques under pressure.
"The DAS guidelines stress that oxygenation takes precedence over everything else during the execution of each plan, and that the best available help should be sought early in cases of difficulty."
Use this template for your briefing:
- Plan A: Direct/video laryngoscopy, maximum 3 attempts with optimisation between each
- Plan B: Second-generation supraglottic airway (e.g., i-gel, LMA Supreme)
- Plan C: Face mask ventilation with two-person technique and airway adjuncts
- Plan D: Surgical cricothyroidotomy if cannot intubate, cannot oxygenate (CICO)
Assign roles and check equipment
Delegate specific tasks to each team member before you start. One person manages drugs and monitoring, another provides airway assistance (BURP, suction), and a third acts as your procedural time-keeper who will declare attempt numbers and call for help when needed. Your time-keeper prevents the team from losing track of how many attempts have occurred, a common problem identified in NAP4 cases.
Confirm your backup equipment is immediately available. Point to the supraglottic airway, bougie, surgical airway kit, and videolaryngoscope while your team watches. Physical confirmation beats assumptions when stress narrows your visual field during a failed intubation.
Step 2. Define failed intubation and call for help
You must declare failed intubation at a specific, predetermined point rather than waiting until the patient crashes. The 2015 DAS guidelines recommend a maximum of three attempts plus one by your most experienced operator (3+1 rule), but many Australian ICUs and EDs now use stricter two-attempt limits to reduce trauma and hypoxia. Your failed intubation algorithm works only if you commit to these limits before you start and stick to them when difficulty occurs.
Set clear failure criteria
Declare failed intubation after three attempts at laryngoscopy with optimisation between each, or immediately after two attempts if oxygenation deteriorates below 90% despite face mask ventilation. Each attempt counts when the laryngoscope blade enters the patient’s mouth, regardless of whether you placed the endotracheal tube. Your time-keeper should announce attempt numbers aloud so the entire team knows where you sit in the algorithm.
"The 2015 DAS guidelines recommend a maximum of three attempts plus one by your most experienced operator (3+1 rule)."
These criteria trigger your declaration:
- Three laryngoscopy attempts with optimal technique (different blade, BURP, bougie)
- SpO₂ below 90% despite bag-mask ventilation between attempts
- Visible trauma to airway structures (bleeding, oedema)
- Loss of laryngeal view that worsens with each attempt
Stop immediately if you cannot maintain oxygen saturations above 90% between attempts. Oxygenation always takes priority over intubation. Your failed intubation algorithm shifts focus from securing the airway to maintaining oxygenation until help arrives or you establish a surgical airway.
Make the help call early
Call for senior help after your second failed attempt, not after the third. NAP4 data showed that teams who delayed calling for assistance until CICO situations developed had significantly worse outcomes than those who escalated early. Your senior colleague needs time to arrive, assess, and attempt Plan B before you exhaust all upper airway options.
Specify exactly who to call during your pre-intubation brief. Most hospitals use this hierarchy:
- Duty anaesthetist or airway specialist (first call, after attempt 2)
- ICU consultant or ED consultant (concurrent with first call)
- ENT or general surgery (for surgical airway, when Plan C fails)
- MET or code blue team (if cardiac arrest imminent)
Your help call should state: "Failed intubation after [number] attempts, patient SpO₂ [value], moving to Plan B, senior assistance required immediately." This structured communication tells your backup exactly what you’ve tried and what comes next in your failed intubation algorithm.
Step 3. Work through Plans A to D
Your failed intubation algorithm progresses through four escalating plans, each with specific triggers, technique requirements, and defined failure points. The DAS 2015 guidelines and Vortex approach both structure these plans to maintain oxygenation while attempting intubation, then abandon intubation attempts when oxygenation fails. You move forward through the plans only after optimal attempts at the current level, never because you’ve simply tried the same technique multiple times without changing your approach.
Plan A: Optimise each laryngoscopy attempt
Plan A allows a maximum of three laryngoscopy attempts with mandatory optimisation between each. Your first attempt sets the baseline, but your second and third attempts must change something significant or you’re simply repeating a failed technique. The DAS guidelines specify that each attempt should use external laryngeal manipulation (bimanual laryngoscopy, not cricoid pressure), consider a different blade type or size, and employ a bougie or stylet if not already used.
Apply these five optimisation strategies between attempts:
- Manipulations: Head extension, jaw thrust, ear-to-sternal-notch positioning, bimanual laryngoscopy
- Adjuncts: Bougie, stylet, different laryngoscope blade (Mac vs Miller), videolaryngoscope
- Size and type: Smaller endotracheal tube, different laryngoscope handle length
- Suction: Clear blood, secretions, vomitus that obscure your view
- Muscle relaxation: Ensure adequate neuromuscular blockade has occurred
Switch to videolaryngoscopy for your second or third attempt if available. The 2015 DAS update explicitly includes video laryngoscopy as a Plan A technique, and evidence shows it improves first-pass success rates in difficult airways. Declare failed intubation after three attempts or immediately if oxygenation deteriorates below 90% despite face mask ventilation between attempts.
Plan B: Insert a supraglottic airway device
Move to Plan B after declaring failed intubation. Insert a second-generation supraglottic airway device (SAD) such as an i-gel, LMA Supreme, or Proseal LMA to restore oxygenation. The 2015 DAS guidelines specify second-generation devices because they provide better seals for positive pressure ventilation and reduce aspiration risk compared to first-generation devices. You’re not trying to intubate through the SAD unless you have specific training and equipment; your goal is oxygenation only.
"Plan B focuses on oxygenation using a SAD, with less emphasis on intubation through a SAD, though this remains an option."
Allow a maximum of three insertion attempts with the SAD. Optimise between attempts by adjusting size, depth, or rotation. Remove cricoid pressure if it was applied, as it impairs SAD insertion and seal. Confirm effective ventilation with visible chest rise, bilateral air entry, and a square-wave capnography trace. If you achieve adequate oxygenation (SpO₂ rising, ETCO₂ trace present), you’ve reached what the Vortex approach calls the "Green Zone" and can pause to plan your next move.
Fibroscopic intubation through an intubating LMA (ILMA) remains an option if you have the equipment and training, but the DAS guidelines discourage blind techniques. Your priority stays oxygenation, not intubation. Move to Plan C if you cannot oxygenate after three SAD attempts or if oxygen saturations continue falling despite apparently correct SAD placement.
Plan C: Face mask oxygenation
Plan C returns to bag-mask ventilation as your sole method of oxygenation. Use a two-person technique with one operator holding the mask seal while another squeezes the bag. This technique generates better tidal volumes and mask seal than single-person attempts. Insert oropharyngeal and nasopharyngeal airways if not already in place, position the patient’s head optimally (ear-to-sternal-notch), and consider deeper muscle relaxation if the patient is not fully relaxed.
Apply these techniques to improve face mask ventilation:
- Two-handed mask seal: Thenar eminences on mask, fingers lift mandible
- Two-person technique: One person maintains seal, second person bags
- Airway adjuncts: Size 3-4 oropharyngeal airway plus 6-7mm nasopharyngeal airway
- Head position: Sniffing position or reverse Trendelenburg if obese
- PEEP valve: 5-10 cmH₂O PEEP improves oxygenation and reduces gastric insufflation
Success in Plan C means you’ve restored oxygenation and bought time to wake the patient (if possible) or mobilise resources for a controlled tracheostomy. Failure in Plan C means you face a cannot intubate, cannot oxygenate (CICO) situation and must immediately move to Plan D. The trigger for Plan D is clear: you cannot maintain SpO₂ above 90% despite optimal attempts at face mask ventilation.
Plan D: Perform surgical cricothyroidotomy
Plan D addresses the CICO emergency where all upper airway techniques have failed and hypoxia threatens cardiac arrest. Perform a surgical cricothyroidotomy using the scalpel-bougie-tube technique, which the DAS guidelines now recommend as the default approach over needle techniques. You need to establish an airway within 60-90 seconds to prevent brain injury.
The surgical technique follows these steps:
- Identify anatomy: Palpate the cricothyroid membrane (laryngeal handshake)
- Vertical incision: 4-5 cm vertical skin incision through skin and subcutaneous tissue
- Horizontal stab: Horizontal stab through cricothyroid membrane with scalpel
- Bougie insertion: Insert bougie through membrane, direct caudally
- Dilate: Railroad a size 6.0 cuffed endotracheal tube over bougie
- Confirm: Inflate cuff, ventilate, confirm with capnography
Your failed intubation algorithm ends when you establish ventilation through any route: endotracheal, supraglottic, or surgical. The algorithm’s purpose is preventing cognitive fixation and ensuring you exhaust all reasonable options before moving to increasingly invasive techniques, always prioritising oxygenation over intubation success.
Step 4. Use checklists and cognitive aids
Checklists prevent you from forgetting critical steps when stress narrows your focus during a failed intubation. The NAP4 audit found that 74% of ICU airway deaths involved failure to use capnography, a basic monitoring step that checklists catch before you induce. Your pre-intubation checklist should sit on every emergency trolley as a laminated card that your team reads aloud before touching the laryngoscope, similar to surgical time-out protocols.
Pre-intubation checklist template
Run through this checklist as a challenge-response dialogue with your team, with each member confirming their assigned tasks. The process takes less than 60 seconds but catches equipment failures, monitoring gaps, and planning oversights before they become disasters.
Pre-Intubation Safety Checklist:
- Patient identity confirmed, indication for intubation stated
- IV access confirmed, monitoring attached (SpO₂, ETCO₂, ECG, BP)
- Pre-oxygenation completed (3 minutes or 8 vital capacity breaths)
- Drugs drawn up and labelled (induction agent, muscle relaxant, vasopressor)
- Laryngoscope tested, backup blade available, suction working
- Endotracheal tube cuff tested, size 6.0-8.0 available
- Bougie, stylet, videolaryngoscope at bedside
- Plans A through D verbalised, team roles assigned
- Second-generation supraglottic airway (Plan B) and surgical airway kit (Plan D) confirmed
Cognitive aids for real-time use
Display your failed intubation algorithm as a visual flowchart on the wall above your emergency trolley so any team member can reference it during an airway crisis. The Emergency Airway Cognitive Tool developed by CCAM combines the DAS algorithm structure with Vortex decision points, giving you attempt limits and escalation triggers on a single A4 page.
"Teams that verbalise Plans A through D before induction reduce the chance of cognitive fixation when difficulty occurs."
Print the DAS 2015 guidelines algorithm and the Vortex diagram, then laminate both as quick-reference cards. Your time-keeper should hold these cards during intubation and read out the next step when you declare Plan A, B, or C failure. Physical cognitive aids override the fixation reflex that makes stressed operators repeat failing techniques instead of following their failed intubation algorithm.
Key points
Your failed intubation algorithm succeeds when you follow three principles: set attempt limits before you start, prioritise oxygenation over intubation, and escalate early rather than persist with failing techniques. The 3+1 rule (three attempts plus one by your most experienced operator) prevents the airway trauma and hypoxia that Mort’s study linked to cardiac arrest and aspiration. Declare failure after three optimised attempts or immediately when SpO₂ drops below 90% despite bag-mask ventilation between attempts.
Cognitive aids and pre-intubation checklists override the fixation reflex that makes stressed operators repeat the same technique. Your team needs to verbalise Plans A through D before induction, assign specific roles to each member, and keep laminated algorithms visible during every emergency intubation attempt.
Parasol Medical Training’s ALS courses teach you to apply these protocols through hands-on simulation with expert instructors, giving you the confidence and skills to manage airway emergencies under pressure.
