A Stridor-Compromised Floor-of-Mouth Abscess and a Three-Hour Consultant Gap
A 48-year-old man (BMI 43 kg/m², poorly compliant with CPAP for obstructive sleep apnoea) presents with a 5-day history of a rapidly enlarging left submandibular abscess. He is afebrile but has trismus limiting mouth opening to 1.5 cm, a firm woody floor of mouth, and inspiratory stridor that appears only when he lies flat. SpO2 is 96% on room air while sitting upright. CT shows a 4 × 3 cm collection with early retropharyngeal extension and bulging of the posterior pharyngeal wall, but no frank airway deviation. Mallampati is unassessable, thyromental distance 5 cm, neck circumference 47 cm, and he received 60 Gy of neck radiotherapy three years ago for laryngeal cancer. ENT wants to incise and drain in theatre within the hour, but the on-call consultant anaesthetist is covering another hospital and will not arrive for three hours. The patient is drowsy but rousable and has consented to surgery.
1. Outline the airway plan you would use in theatre, justifying each element against this patient's specific risk factors.
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Recognise what makes this dangerous. This is not just a predicted difficult airway - it is potentially an obstructed one: woody floor of mouth, retropharyngeal extension, stridor when supine, obesity, short thyromental distance, and irradiated tissues that will be fibrosed and poorly compliant. Paralysis or loss of spontaneous ventilation could convert a partial obstruction into a complete one within seconds, and bag-mask rescue may be impossible because the pharyngeal pathology sits where the airway is splinted.
Core principle: secure the airway while he is awake and breathing, with a surgical fallback already scrubbed.
Plan A - awake technique. Topicalise with nebulised 4% lidocaine to a maximum of 4.5 mg/kg, plus cocaine or lidocaine-adrenaline to the nasal mucosa. High-flow nasal oxygen at 60–70 L/min throughout to widen the safe apnoea window and reduce desaturation if the airway is briefly lost. Light sedation only - remifentanil TCI 0.5–1.5 ng/mL or dexmedetomidine - never a dose that suppresses respiration or airway tone.
Route: with trismus of 1.5 cm, a videolaryngoscope blade will not enter, so a nasal flexible scope is the realistic endoscopic option. Given radiotherapy and retropharyngeal extension, though, my primary plan would be an awake elective tracheostomy under local anaesthetic by ENT, scrubbed and ready in theatre, converting to general anaesthesia only once the airway is definitive.
Backup ladder: awake tracheostomy is Plan A/B rather than Plan C; Plan C is surgical cricothyroidotomy if the airway is lost before the tracheostomy is established.
2. During awake nasal endoscopy the view is grade 4 (epiglottis not visible), the patient's SpO2 falls to 78% and he becomes agitated, and the surgeon has not yet scrubbed. Describe your next steps in order.
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Immediate actions, in sequence:
- Stop and declare the problem aloud - "possible cannot intubate, cannot oxygenate" - and call for additional hands and the difficult airway trolley. Do not persist with endoscopy; further attempts at an obstructed, bleeding airway cause trauma and worsening oedema.
- Remove the scope and apply 100% oxygen by facemask with two-person technique, jaw thrust, an oropharyngeal airway only if tolerated (trismus 1.5 cm may permit a small one), and continue high-flow nasal oxygen. Sit him up if that is how he self-opens his airway - in floor-of-mouth pathology, posture is part of the airway.
- Assess ventilation, not intubation. If the chest rises and SpO2 recovers, oxygenate, re-topicalise and re-plan with the ENT surgeon scrubbed before any further attempt.
- If he cannot be oxygenated - falling saturation with no chest movement - a second-generation supraglottic airway is unlikely to be insertable through 1.5 cm of trismus, so move directly to front-of-neck access: scalpel cricothyroidotomy (scalpel–bougie–tube). If ENT is in the room but unscubbed, their hands are still the fastest route to a surgical airway and I would call for it while I prepare the neck.
The root cause that must be named in the debrief: the ENT surgeon should have been scrubbed and draped before any instrumentation began. This scenario is exactly why the rule exists.
3. Justify whether you would proceed before the consultant anaesthetist arrives, and how you would document the decision.
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The conflict: delaying three hours risks progressive airway obstruction - retropharyngeal extension plus stridor can obstruct unpredictably and rapidly. Proceeding without the most senior anaesthetist concentrates risk in the least experienced pair of hands.
What I would do:
- Call the consultant immediately and ask them to attend; also involve the on-site consultant surgeon, the theatre manager and, if available, an intensive care consultant - this is an institutional escalation, not just a personal decision.
- Consider whether the safest option is transfer to a centre with immediate ENT/anaesthetic cover; for an airway at this stage, transfer itself carries risk and is only preferable if the local team genuinely cannot secure the airway.
- If the airway is deteriorating at rest (drooling, inability to lie flat, changing voice, rising respiratory rate), I would proceed with an awake tracheostomy performed by ENT under local anaesthesia, which is the intervention that most reliably secures the airway and requires the least anaesthetic skill. The anaesthetist's role then is sedation, oxygenation and haemodynamics.
Documentation must record: the seniority of those present and the consultant's advice and time of call; the Plan A/B/C/D written in the notes and briefed aloud; the patient's consent and understanding; the reasoning that airway compromise outweighed the risk of waiting; and the names of all team members. A contemporaneous, reasoned entry is what protects both the patient and the trainee.