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Difficult Airway — CICO Algorithm
TEXTCrisis II · 10 min read
ASA 2022. Limit attempts, escalate decisively, declare CICO when oxygenation failing. Don't delay surgical airway.
After this lesson you can
3 min read8 sections- Recall the ASA 2022 Difficult Airway Algorithm decision points.
- Predict difficult airway using LEMON + MOANS + RODS.
- Choose between awake intubation and asleep induction in a predicted difficult airway.
- Execute scalpel-bougie-tube cricothyrotomy when CICO declared.
Predict before you induce — bedside exam
- Mallampati 3-4
- thyromental distance <6 cm
- mouth opening <3 cm (≈ 2 finger-breadths)
- neck extension limited
- large tongue
- retrognathia
- prior radiation or surgery
- OSA
- BMI >35
- neck circumference >43 cm (men) / 41 cm (women)
- prior 'difficult intubation' history
- LEMON (Look · Evaluate 3-3-2 · Mallampati · Obstruction · Neck mobility)
- MOANS (difficult mask)
- RODS (difficult SGA)
- SHORT (difficult cric)
Document positive predictors triggers anticipated-difficult plan.
ASA 2022 algorithm overview
Anticipated: awake intubation (flexible scope or video laryngoscopy) — preserves spontaneous ventilation, no commitment until tube is in.
Unanticipated post-induction failure: limit attempts, optimize next attempt, declare and escalate.
The 2022 update emphasizes earlier SGA rescue, lower threshold for FONA, and explicit awake-vs-asleep + extubation-strategy decision points.
Print the algorithm on every OR wall — cognitive offloading saves lives in the 90 seconds you have.
Plan A — optimize, then ≤3 attempts
100% O₂ preoxygenation 3-5 min, apneic oxygenation 15 L/min nasal cannula throughout.
- bougie first-pass (DAS recommends)
- OELM (optimal external laryngeal manipulation) for view improvement
- hyperangulated stylet for video laryngoscopy
Limit to 3 attempts total — each pass causes edema + worsens the next attempt + drives hypoxia.
Change SOMETHING between attempts: operator, blade, technique, head position.
If three attempts fail with adequate oxygenation, transition to Plan B before SpO₂ drops below 90%.
Plan B — SGA rescue (max 3 attempts)
- 4 for <70 kg
- 5 for 70-100 kg
- 6 for >100 kg (adjust by exam)
After insertion, confirm ventilation: chest rise, ETCO₂ waveform, audible breath sounds, SpO₂.
If SGA ventilation good: decide intubate-through-SGA (Aintree exchange catheter + fiberoptic) vs wake-and-regroup vs proceed with SGA for the case.
If SGA fails after 3 attempts or oxygenation degrading: Plan C immediately.
Plan C — face mask + wake-vs-FONA decision
- two-handed thumbs-down grip
- oral + nasal airway
- jaw thrust by assistant
- PEEP
5-10 cmH₂O
If mask works elective case: wake patient, plan awake technique.
Emergent case: proceed with mask anesthesia or commit to surgical airway.
If mask fails AND SpO₂ falling AND SGA failed CICO declared.
The CICO clinical state is defined by hypoxia despite all three rescue modes — not by your emotional state.
Declare it out loud: 'I am declaring CICO.
Going to FONA now.'
Plan D — FONA (scalpel-bougie-tube)
- scalpel #10
- bougie
- 6.0 cuffed ETT
Technique: identify cricothyroid membrane (palpate notch of thyroid cartilage, slide down to first prominent ring = cricoid, membrane between them).
Stabilize larynx with non-dominant hand.
Target time from declaration to ventilation: ≤90 seconds.
Needle cric is rescue only — much higher failure rate.
Awake intubation when predicted
- glycopyrrolate
0.2 mg IV(antisialogogue) - 4% nebulized lidocaine
4 mLvia mask 10 min - then aggressive topicalization
Nerve blocks for severe: superior laryngeal nerve (internal branch — at hyoid), transtracheal lidocaine 4 mL through cricothyroid membrane (numbs trachea + vocal cords).
Sedation: dexmedetomidine load 1 mcg/kg over 10 min + 0.5 mcg/kg/hr maintenance, ± remifentanil 0.025-0.05 mcg/kg/min.
Avoid airway-obtundant doses — patient must protect own airway.
Confirm tube position with capnography BEFORE inducing.
Extubation of the difficult airway
Risk-stratify: minor manipulation + brief intubation = standard extubation.
Multiple attempts, edema, surgery near airway, prolonged intubation = high-risk extubation.
- cuff leak test (audible leak with cuff deflated suggests adequate edema room)
- staged extubation over airway exchange catheter (AEC) keeps a conduit for reintubation
- dexmedetomidine to ease emergence
- head-up position
- ENT/surgical airway team available
Counsel patient pre-op + document predictors and difficulties in the airway alert/MedAlert system for future encounters.
⚠ Common pitfalls
- Failing to call for help early — the algorithm specifies it BEFORE the third attempt.
- Repeating the same blade with the same technique — change something each attempt or escalate.
- Reaching for fiberoptic in a CICO emergency — too slow; FONA is the answer once SGA fails.
- Confusing 'can't intubate, can ventilate' with CICO — both protocols differ; CIV allows wake-up if elective.
💎 Clinical pearls
- Mandible-to-hyoid distance ≤3 fingerbreadths is a stronger predictor than Mallampati alone.
- AFOI in a known difficult airway is rarely regretted; asleep induction in the same case can be.
- FONA: horizontal stab, rotate scalpel 90°, finger-track, bougie, tube — practice on a manikin before you need it.
- Document the difficult airway in the chart AND give the patient a letter; this is a national-registry-worthy event.
Recap
- Mandible-to-hyoid distance ≤3 fingerbreadths is a stronger predictor than Mallampati alone.
- AFOI in a known difficult airway is rarely regretted; asleep induction in the same case can be.
- FONA: horizontal stab, rotate scalpel 90°, finger-track, bougie, tube — practice on a manikin before you need it.
- Document the difficult airway in the chart AND give the patient a letter; this is a national-registry-worthy event.
Mark each section done to complete the module.