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ENT — Shared Airway, Jet, Laser

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Specialty II · 9 min read

Throat pack count is a sentinel event prevention. Laser airway means FiO₂ ≤30%. Pediatric T&A + OSA = overnight monitoring.

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Plan shared-airway anesthesia.
Manage controlled hypotension for sinus/FESS.
Recognize laser-airway fire risk.
Anticipate post-op airway swelling.

Shared-airway principle + communication

KeyENT surgery places the surgeon and anesthetist in the same physical space — the airway.

Every step requires explicit communication.

Pre-op huddle

what tube
what FiO₂
laser yes/no
who removes the throat pack
who confirms tube position post-positioning

Tube choice by procedure: RAE preformed (oral curve down for ENT/dental/oral max-fac; nasal curve up for intraoral procedures), reinforced wire-wound for any case with extreme positioning or laser, microlaryngeal small-bore (4.5-6.0 cuffed) for laryngeal microsurgery.

Discuss EXTUBATION plan pre-op — some patients (deep neck infection, supraglottic edema, prolonged intubation) need awake fiberoptic exchange or AEC-mediated staged extubation.

Tonsillectomy considerations: postoperative bleeding risk (primary <24h, secondary 5-10 days), pediatric OSA, multimodal analgesia avoiding heavy opioids, antiemetics. Monitor for hypovolemia and aspiration risk; awake extubation with full reversal in lateral or recovery position.

Throat pack count — never miss this

KeyThroat pack inserted by surgeon to absorb blood + prevent aspiration of operative debris.

MUST BE REMOVED before extubation — a retained throat pack is a sentinel airway disaster causing complete obstruction, hypoxic arrest, death.

Closed-claim case studies confirm fatalities.

Pack must be on the SURGICAL COUNT and verified removed before extubation.

Many institutions mandate

visible end of pack outside the mouth at all times
or visible label tag clipped to the patient/ETT
or a specific 'pack in / pack out' verbal verification between surgeon + anesthesia

Document insertion + removal times in anesthesia record.

Two-person verification standard.

Tracheal stenosis management: Cotton-Myer grading I-IV, assessed by CT and bronchoscopy. Anesthetic considerations: smaller ETT below stenosis, jet ventilation or apneic oxygenation for laser/dilation, plan for surgical airway; team communication and equipment prep critical.

Laser airway fire prevention

KeyFire triad: OXIDIZER (O₂, N₂O) + IGNITION (laser, electrocautery) + FUEL (ETT, drapes, alcohol prep, blood, methane in bowel gas).

Laser airway = highest fire risk in anesthesia.

Mitigations: laser-resistant ETT (stainless-steel or foil-wrapped, saline-filled dual cuff with methylene blue tint to signal puncture), FiO₂ ≤30% (if SpO₂ permits — preempt the patient with N₂-blended air), NO N₂O (oxidizer almost as strong as O₂), saline-filled cuff + wet gauze pack around tube.

Pre-rehearsed FIRE ALGORITHM

stop O₂ + N₂O
disconnect circuit
remove burning ETT
flood field with saline
mask-ventilate with room air via new circuit
bronchoscopy to assess thermal injury
admit ICU

ASA OR Fire Algorithm 2013 in every anesthesia workstation.

Laser airway fire prevention: triad of fuel (ETT/drapes), ignition (laser), oxidizer (O2/N2O). Strategies: lowest FiO2 (<30%), avoid N2O, use laser-resistant ETT, fill cuff with saline + methylene blue, wet gauze around ETT; have water/saline ready for immediate fire.

FESS controlled hypotension + bloodless field

KeyFunctional endoscopic sinus surgery is performed in a tight space adjacent to intracranial structures (cribriform plate, orbit).

A bloodless field improves surgical safety and outcome — even small bleeding obscures view and increases risk of dural penetration or orbital injury.

Strategies

head elevation 15-30°
controlled hypotension MAP 60-70 mmHg via TIVA + remifentanil (cleanest control)
volatile + esmolol or clevidipine infusion
TXA 1 g IV at induction

Topical decongestant injection by surgeon (lidocaine + epinephrine — watch for cardiac stimulation from absorbed epi).

CONTRAINDICATIONS to deep hypotension: CAD with active angina, prior stroke, severe carotid disease, advanced glaucoma — modify the target.

Surgical fire prevention strategies: use lowest FiO2 acceptable (<30% near cautery), avoid N2O, allow alcohol prep to dry 3 min, communicate before cautery use, perform pre-induction fire safety check.

Pediatric tonsillectomy + adenoidectomy

KeyPediatric T&A is one of the most common pediatric surgeries — also one of the highest-acuity ambulatory cases because the patient typically has OSA.

RISK STRATIFICATION for postop respiratory complications: severe OSA (AHI >10 by polysomnography, or witnessed apnea with hypoxia at home), age <3, BMI >95th percentile, syndromic patient (Down's, craniofacial).

High-risk patients require OVERNIGHT MONITORING with continuous SpO2.

Pre-op CPAP if used at home.

Multimodal opioid-sparing analgesia: scheduled APAP + NSAID (ketorolac post-hemostasis if surgeon agrees) + dexamethasone 0.1-0.5 mg/kg (antiemetic + reduces post-T&A pain + reduces edema; debated bleeding risk in recent meta-analyses — confirm with surgeon).

AVOID codeine + tramadol per FDA black box (CYP2D6 ultra-rapid metabolizer deaths).

Obstructive sleep apnea (OSA) perioperative management: STOP-BANG screening, CPAP continuation, opioid-sparing analgesia, regional preferred, post-op monitoring with continuous SpO2, semi-upright positioning to reduce upper airway collapse.

Post-tonsillectomy bleeding — the emergency return

KeyBleeding 5-10 days post-tonsillectomy is an AIRWAY EMERGENCY.

Patient returns to OR with

full stomach (swallowed blood)
active airway bleeding
hypovolemia from ongoing loss
anxiety + potentially uncooperative pediatric patient

Preparation: large-bore IV (or two if possible) + warmed crystalloid bolus + blood ordered + 'just-in-case' difficult-airway cart at bedside.

Position ramped/upright.

Two functioning suctions ready.

Surgeon scrubbed and ready.

INDUCTIONreduced dose etomidate or ketamine + sux 1.5 mg/kg or roc 1.2 mg/kg + sugammadex backup.

Video laryngoscope + large-bore Yankauer suction.

Have backup SGA + surgical airway available.

Extubate awake after hemostasis confirmed.

Tonsillectomy anesthesia: assess OSA (most common indication), risk of post-tonsillectomy bleeding (5-10 days post-op), and bleeding tonsil requires RSI with full stomach precautions and adequate IV access.

Jet ventilation for laryngeal surgery

KeyUsed for surgery requiring an unobstructed laryngeal view (microlaryngeal surgery, vocal cord papilloma, supraglottic biopsy).

Two modes: LOW-FREQUENCY jet (1-2 Hz, manually triggered with high-pressure O₂ via subglottic catheter or supraglottic Sanders injector) — visible chest rise + relies on entrainment.

HIGH-FREQUENCY jet ventilation (HFJV, 100-300 breaths/min via electronically driven driving pressure) — minimal chest motion + better surgical conditions.

Risks

barotrauma + pneumothorax if outflow obstructed (open glottis required)
gastric distension
hypercarbia (must monitor blood gas)
aspiration of debris

NO N₂O (oxidizer) and PEEP not feasible.

TIVA technique (propofol + remi) standard since no inhaled volatile via these systems.

Jet ventilation setup with O2 source, pressure regulator (15-25 psi adult, 5-10 peds), manometer, tubing, jet injector, and ETT/cricothyrotomy port; contraindicated in severe obstructive lung disease and air trapping risk.

Other ENT-specific concerns

KeyMIDDLE EAR + MASTOID surgery: N₂O contraindicated (diffuses into closed air space + raises pressure graft displacement, tympanic perforation).

Anti-emetics for vestibular cases (dex + 5HT3 + scopolamine).

LARYNGECTOMY/RADICAL NECK

anticipated difficult airway from radiation + tumor awake fiberoptic intubation

high blood loss T&S

carotid sinus stimulation by surgical manipulation bradycardia/asystole (atropine + alert surgeon)

recurrent laryngeal nerve monitoring don't paralyze long-term, allow reversal for nerve identification

THYROID surgery

same recurrent laryngeal concerns

post-extubation stridor from edema or vocal cord paralysis

hypocalcemia from parathyroid removal late symptom

ASA Difficult Airway Algorithm 2022 - main path: assess airway and risk of difficult airway, optimize position/preoxygenation, awake intubation if anticipated difficult; if intubation fails - SGA, face mask, surgical airway; awaken if able.

⚠ Common pitfalls

Routine FiO₂ 100% near laser/cautery in the airway — fire triad complete.
Forgetting throat-pack count — leaving one in = airway obstruction.
TIVA without depth monitoring during controlled hypotension — awareness risk.
Tonsillectomy without bleeding plan — primary + secondary post-tonsillectomy bleeds need RSI.

💎 Clinical pearls

Laser cases: FiO₂ ≤30%, laser-resistant ETT, cuff filled with saline + methylene blue.
Controlled hypotension to MAP ~60-65 — short-acting (esmolol, nitro, remi) preferred over inotropic suppression.
Post-tonsillectomy bleed: full stomach + difficult airway (blood, edema) — RSI with all equipment ready.
Bronchoscopy: jet ventilation, SGA, or apneic technique; close communication with surgeon mandatory.

Recap

Laser cases: FiO₂ ≤30%, laser-resistant ETT, cuff filled with saline + methylene blue.
Controlled hypotension to MAP ~60-65 — short-acting (esmolol, nitro, remi) preferred over inotropic suppression.
Post-tonsillectomy bleed: full stomach + difficult airway (blood, edema) — RSI with all equipment ready.
Bronchoscopy: jet ventilation, SGA, or apneic technique; close communication with surgeon mandatory.

Mark each section done to complete the module.