Awake Airway in a Substernal Goiter with Fixed Tracheal Compression
A 61-year-old woman (92 kg, BMI 34) is scheduled for total thyroidectomy for a multinodular goiter. She reports increasing hoarseness and stridor when climbing stairs; at rest she is comfortable, with SpO2 96% on room air. CT shows a 9 cm goiter with substernal extension and tracheal compression to 8 mm at the thoracic inlet, with 20° rightward deviation. Airway examination: mouth opening 3.2 cm, Mallampati 3, thyromental distance 5 cm, limited neck extension, and a firm mass that does not move with swallowing. She has never had anesthesia. The surgeon requests muscle relaxation and a "standard tube," and plans to extubate in the OR. Available: flexible bronchoscope, videolaryngoscope with hyperangulated blade, armored tubes 5.0–7.0 mm, and a surgeon who can perform emergent tracheostomy only after the neck is open.
1. Outline your airway plan from the preinduction period through tube placement, and justify each choice against the CT and examination findings.
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Plan: awake flexible bronchoscopic intubation with spontaneous ventilation preserved.
- Why awake: the CT shows a fixed 8 mm narrowing at the thoracic inlet. Asleep induction plus positive-pressure ventilation risks losing the airway above a fixed obstruction, and mask ventilation or a supraglottic device will not bypass it.
- Tube choice: a 5.5 mm ID armored tube (OD ≈ 7.5 mm) passes an 8 mm lumen; a routine 7.5 mm tube will not. Armored tubing resists kinking when the neck is positioned or compressed.
- Preparation: topicalize with 4% lidocaine to the oropharynx and 2% to the cords/trachea, keeping total dose ≤4–5 mg/kg; glycopyrrolate 0.2 mg for secretions; semi-upright position; nasal cannula 15 L/min; standard monitors plus arterial line; surgeon scrubbed and in the room.
- Sequence: scope through the cords under direct vision, rail the tube, confirm position fiberoptically and with capnography, then induce. No muscle relaxant until the tube is confirmed in the trachea.
- Backup: videolaryngoscope with hyperangulated blade, bougie, 5.0 mm tube, rigid bronchoscope, and a pre-briefed plan for emergent surgical airway.
Each step protects spontaneous ventilation until the airway is secured below the stenosis.
2. During awake bronchoscopy the patient coughs, the scope comes out, and SpO2 falls to 84% with audible stridor. What do you do next, and why is this different from a routine "cannot intubate" event?
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Immediate actions:
- Sit the patient fully upright, 100% oxygen by tight-fitting mask with CPAP if tolerated, and coach slow breathing; do not force supine positioning.
- Stop stimulation, suction secretions, and re-topicalize with nebulized lidocaine 4% (≤4 mg/kg) to break the cough–spasm–desaturation cycle.
- Call for the second anesthesiologist and ENT immediately, and have the difficult-airway cart and rigid bronchoscope at the bedside.
- If the patient stabilizes, consider inhalational induction with sevoflurane maintaining spontaneous ventilation, or proceed to awake videolaryngoscopy if the cords can be visualized.
Why this is not a standard CICO: the obstruction is fixed and subglottic/at the thoracic inlet. Positive-pressure mask ventilation may be ineffective or worsen barotrauma, an LMA sits above the lesion, and a cricothyrotomy below the cords may also be below or at the stenosis. The patient can still move air, which is the lifeline-protect it rather than abolish it. If total obstruction develops, the options are rigid bronchoscopy, emergent open tracheostomy below the mass, or, in extremis, cardiopulmonary bypass.
3. The goiter is removed, the trachea now measures 12 mm, and the surgeon wants extubation in the OR. What determines your decision, and how does suspected tracheomalacia change it?
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Criteria before extubation:
- Cuff-leak test with the patient breathing spontaneously; an absent leak suggests laryngeal edema.
- Fiberoptic inspection of the cords and trachea, awake and following commands, adequate tidal volumes off pressure support, normothermia, and normal ionized calcium (hypocalcemia after total thyroidectomy can cause stridor and laryngospasm).
- Patent drains, no expanding neck hematoma, and the surgeon physically present.
If tracheomalacia is suspected (long-standing compression can cause dynamic expiratory collapse at the site), keeping the patient intubated and sedated for 12–24 hours with low positive end-expiratory pressure splints the airway while tone recovers, and allows re-examination. Extubating a collapsing trachea in the OR is the wrong judgment call.
Postextubation safety: sit upright, humidified oxygen, dexamethasone 8 mg, continuous observation in a high-acuity area, difficult-airway cart available, and a low threshold to reopen the wound for hematoma-which is a surgical emergency, not a pharmacologic one.