Laryngospasm: Sudden Vocal Cord Closure — Emergency Management and Prevention

Laryngospasm is pathologic over-activation of the laryngeal protective reflex — normally a brief vocal-fold closure to prevent aspiration; in laryngospasm this reflex is prolonged (seconds to minutes) and produces complete obstruction.

Reflex arc (vagal): laryngeal mucosal trigger → internal branch of superior laryngeal nerve (afferent) → vagal nucleus solitarius → vagal motor (nucleus ambiguus) → recurrent laryngeal nerve (efferent) → adductor muscles (lateral cricoarytenoid + thyroarytenoid). Vocal folds close fully + aryepiglottic folds also close — "ball-valve" obstruction.

Adult vs paediatric differences: paediatric laryngeal mucosa more sensitive (heightened reflex), narrower lumen (same swelling = more obstruction), lower oxygen reserve (rapid desaturation). Hence paediatric laryngospasm is more dangerous and requires faster management.

Anaesthetic triggers (commonest clinical context): (1) Induction — vocal fold reflexes still active before adequate depth; laryngoscopy, intubation, foreign body laryngeal contact trigger laryngospasm. (2) Emergence — "light plane" anaesthesia (reflexes back but consciousness not yet adequate) — most common period (especially paediatric); oropharyngeal secretion, blood, foreign body contact trigger. (3) Extubation — superficial anaesthesia and ETT removal irritate larynx. (4) Paediatric URI — heightened mucosal sensitivity, 5-10× laryngospasm risk. (5) Smoking history — chronic mucosal irritation, reflex sensitivity. (6) Reactive airway (asthma, allergy) — bronchospasm + laryngospasm coexist.

Non-anaesthetic triggers: (1) Laryngopharyngeal reflux (LPR) — pepsin + acid irritate laryngeal mucosa, chronic recurrent laryngospasm + cough syndrome ("chronic cough with laryngospasm"); (2) Exercise-induced paradoxical vocal fold motion (EI-PVFM) — vocal folds close on inspiration during exercise — must not be confused with asthma (stridor + dysphonia during attack, no wheezing on auscultation); (3) Foreign body — paediatric swallowing + airway foreign body (small piece, peanut, toy); (4) Cold air exposure — winter sports, sudden cold inhalation; (5) Chemical inhalation — chlorinated pool, cleaning chemicals, acute military chemical exposure; (6) Psychogenic — anxiety, panic attack, conversion (often young woman); (7) Tetany — hypocalcaemia (post-parathyroidectomy acute hypocalcaemia can cause laryngospasm — rare complication post emergency surgery).

Incidence: 1% general anaesthesia rate; paediatric anaesthesia 8-9% (3-4× adult); rises to 20-25% with paediatric URI. General population chronic laryngospasm: rare, exact data scarce. Related overview: our general ENT services.

Typical clinical features of laryngospasm: sudden respiratory distress, stridor (inspiratory — high-pitched whistle), intense breathing effort (accessory muscle use — sternocleidomastoid, intercostal retractions), paradoxical chest movement, cyanosis (late — initial saturation normal), neck + face venous distension (high intrathoracic pressure), no voice (complete vocal fold closure), panic + restlessness (in adult + older child), hypertension + tachycardia (sympathetic activation).

Severity classification: (1) Partial laryngospasm — vocal folds partially open, stridor present, ventilation poor but present, oxygen saturation drops gradually. (2) Complete (total) laryngospasm — vocal folds fully closed, NO stridor (silent — the most severe), ventilation zero, rapid saturation drop + cyanosis + bradycardia (late, hypoxic). Total laryngospasm needs immediate intervention (within seconds).

Differential diagnosis (especially outside anaesthesia context): (1) Bronchospasm — asthma attack; expiratory wheezing dominant, not inspiratory; auscultation shows wheezing; treatment bronchodilator (salbutamol nebuliser); (2) Foreign body aspiration — acute onset, rapid obstruction or later lower-airway obstruction; (3) Epiglottitis — paediatric, fever, drooling, "tripod" position, severely toxic; (4) Croup (laryngotracheobronchitis) — child, barking cough, viral history; (5) Angioedema — allergic, urticaria, mucosal swelling (lip, tongue, larynx) — responds to adrenaline; (6) Vocal fold paralysis — bilateral adductor position — inspiratory stridor, hoarseness; (7) Tracheal stenosis/laryngomalacia — chronic, prominent in younger ages; (8) PVFM (paradoxical vocal fold motion) — exercise- or stress-triggered, brief, resolves spontaneously or with voice therapy.

Diagnosis during anaesthesia: alarms (rising peak inspiratory pressure, ventilator obstruction, falling end-tidal CO2 — zero if uncapnographed), capnograph (no or reduced CO2 trace), oximetry (saturation falls), clinical (neck-face venous distension, retractions).

Diagnosis of chronic laryngospasm in the general population: ENT + fibre-optic nasopharyngolaryngoscopy (FNL) — directly observe paradoxical vocal fold motion during attack or trigger simulation (exercise tolerance test, cold air, trigger inhalant); spirometry (FEV1 normal expiratory, flat inspiratory — flow-volume loop "I-shape" — PVFM typical); LPR screening (24-hour pH-metry + impedance, RSI questionnaire); allergy testing (if allergic component); psychological evaluation (anxiety disorder).

Complications (unmanaged laryngospasm): hypoxic encephalopathy (prolonged — seconds-minutes — brain oxygen lack causes permanent damage), cardiac arrest (hypoxia + bradycardia → asystole — especially fast in paediatrics), negative-pressure pulmonary oedema (NPPE — strong inspiration against closed larynx → high intrathoracic negative pressure → pulmonary capillary permeability rise → oedema; develops within minutes of extubation), rib or cervical spine trauma (strong breathing effort), aspiration (gastric content swallowing — vomiting + laryngospasm together).

Once laryngospasm is identified, rapid systematic intervention is essential — failure to resolve within seconds leads to hypoxic complications.

Step 1 — Trigger removal and positioning: oropharyngeal suction (secretions, blood), foreign body removal (Magill forceps), call for help (anaesthesia team or rapid response), position — pillow elevation, chin up (jaw-thrust + chin-lift), "sniffing" position (nape raised, occiput on bed — open airway).

Step 2 — Larson manoeuvre ("laryngospasm notch"): Larson (1998) described by an anaesthesiologist. Pressure bilaterally at the notch behind angle of mandible (fossa between mastoid + ramus of mandible) + forward pull (jaw-thrust). Mechanism: triggers swallowing reflex causing laryngeal relaxation. Usually effective within 30-60 seconds. Standard first manoeuvre in modern anaesthesia.

Step 3 — Positive pressure ventilation + 100% oxygen: tight face mask (two-handed, with assistant), two-handed jaw-thrust + chin-lift, positive pressure ventilation (PPV) 10-20 cmH2O (excess risks gastric distension + barotrauma); 100% oxygen continuous (denitrogenation — maximise alveolar oxygen reserve). In partial laryngospasm PPV often suffices (small gap between vocal folds can be forced open).

Step 4 — Deep sedation (deepen anaesthesia): propofol 0.5-1 mg/kg IV bolus (adult); paediatric 0.5 mg/kg. Mechanism: deeper anaesthesia suppresses reflex, vocal folds relax. Effective in 30-60 seconds. Usually tried after Steps 1 + 2 + 3.

Step 5 — Muscle relaxant (refractory): succinylcholine 0.1-2 mg/kg IV (mini-dose 0.1-0.5 mg/kg sufficient for relaxation; full 1-2 mg/kg for intubation). If no IV access — intramuscular (deltoid, tongue — 4 mg/kg). Effect within 30-60 seconds. Prepare for endotracheal intubation (laryngoscope + ETT + cuff + balloon).

Step 6 — Emergency surgical airway (last resort): if intubation fails despite relaxation (difficult airway — DAS — Difficult Airway Society algorithm), supraglottic airway (LMA) tried, then if still failing → cricothyroidotomy (surgical airway, midline) or emergency tracheostomy.

Paediatric specifics: rapid desaturation requires VERY RAPID intervention. Steps 1 + 2 + 3 applied in parallel. Propofol paediatric 0.5-1 mg/kg. Succinylcholine (1-2 mg/kg) lower threshold. Atropine (cardiac — bradycardia prophylaxis) considered before succinylcholine (especially in children).

NPPE (Negative-Pressure Pulmonary Oedema) — risk after laryngospasm: pink frothy sputum, high oxygen need, lung crackles, chest X-ray bilateral interstitial-alveolar opacities. Treatment: positive pressure ventilation (CPAP or PEEP if intubated), diuretic (furosemide 20-40 mg IV), oxygen + hospitalised observation (ICU). Usually resolves in 12-24 hours.

General population (non-anaesthetic, ED) laryngospasm: airway management (oxygen, positioning, PPV if needed) + trigger removal + sedation (midazolam IV if needed) + ENT consultation. Investigations (FNL, spirometry, imaging) after the attack. Foreign body suspicion → rigid bronchoscopy.

Prevention — anaesthetic: adequate induction depth (BIS monitor evaluation), optimise intubation conditions (depth + analgesia + relaxation), strict extubation criteria (full wakefulness — eyes open, command following, swallow + cough reflexes returned), defer elective surgery in paediatric URI (3-4 weeks — mucosal sensitivity declines), preoperative smoking cessation (ideally 8 weeks), IV lidocaine (1-1.5 mg/kg) before extubation as prophylaxis (reduces mucosal sensitivity), paediatric magnesium sulphate (15-30 mg/kg).

Post-event follow-up: PACU monitoring, oxygen + monitor, watch for NPPE features (at least 2-4 hours), family communication (post-event psychological support — especially paediatric). For the related clinical reference, see snoring / sleep apnoea page.

Chronic recurrent laryngospasm + paradoxical vocal fold motion (PVFM) is a non-anaesthetic clinical group. Multidisciplinary approach with ENT + pulmonologist + speech-language therapist.

PVFM (Paradoxical Vocal Fold Motion — Vocal Cord Dysfunction VCD): during inspiration vocal folds incorrectly adduct (close) — normally active folds should abduct (open). Result: stridor, dyspnoea, hoarseness, brief "choking" feeling. Confused with asthma attack (misdiagnosed — inhaled therapy ineffective for years). Attack duration: seconds-minutes, often resolves spontaneously or with trigger withdrawal.

PVFM triggers: exercise (exercise-induced PVFM — EI-PVFM — athletes, breathlessness on running), stress + anxiety, LPR (chronic laryngeal irritation), allergens, chemical irritants, rapid temperature change, glossopharyngeal reflex (swallow + cough triggers), strong odour.

Diagnosis: gold standard — fibre-optic nasopharyngolaryngoscopy (FNL) during attack — direct view of vocal folds closing on inspiration. Trigger testing (exercise tolerance test, cold air, chemical — trigger simulation) provokes attack. Spirometry: flow-volume loop with flat inspiratory limb ("I-shape") + normal expiratory. Distinguish from asthma — in asthma both inspiratory and expiratory affected, responds to bronchodilator. PVFM has NO bronchodilator response; sedative or distraction shortens.

PVFM treatment: voice therapy (SLT) is the MAINSTAY. (1) Education — PVFM mechanism, panic as trigger, "break the panic loop"; (2) Breathing techniques — diaphragmatic breathing (abdominal vs chest), slow controlled breathing (4-7-8: 4 second inhale, 7 hold, 8 exhale); (3) "Rescue breathing" manoeuvre at attack onset — slow nasal inhale + slow exhale through partially closed lips encouraging active vocal fold opening (whistle blowing technique); (4) Posture — neck relaxation, shoulders down; (5) Trigger recognition + avoidance. 6-12 sessions suffice in most cases.

CBT (Cognitive Behavioural Therapy): for PVFM attacks with anxiety (especially psychogenic component). Clinical psychologist 8-12 sessions. Trigger recognition + cognitive restructuring + graded exposure + relaxation.

LPR management: high-dose PPI 3-6 months (esomeprazole 40 mg BD), lifestyle (reduce fatty/acidic foods, no late meals, head-of-bed elevation, weight control). Refractory — Nissen fundoplication. LPR treatment reduces PVFM.

Allergy + sinusitis management: trigger reduction. Allergy testing + specific treatment (nasal steroid, antihistamine, AIT if indicated). Treat chronic rhinosinusitis.

Anxiety + panic disorder: SSRI (sertraline, escitalopram), CBT, relaxation. Psychiatry consult.

Botulinum toxin — refractory PVFM: Botox to thyroarytenoid muscle (vocal fold relaxation — reduce adductor force); used when uncontrolled despite voice therapy. Effect 3-4 months; side effects hoarseness + swallowing change. Repeat every 3-6 months. Practised at few centres.

Surgery — very rare indication: posterior cricoarytenoid electrode (laryngeal pacemaker — research), bilateral vocal fold lateralisation surgery (laser cordotomy — last resort).

Typical patient journey: symptoms start → misdiagnosed as asthma → years of ineffective inhaled therapy → ENT referral → FNL during attack or trigger test → PVFM diagnosis → SLT voice therapy + LPR/allergy treatment + CBT → 70-80% achieve meaningful improvement or remission.

Prevention — chronic laryngospasm: trigger recognition (attack diary), LPR + allergy management, anxiety management, regular voice therapy practice (learned techniques applied daily), lifestyle (sleep, nutrition, hydration, avoid smoking-alcohol). Acute attack management (rescue breathing technique) should be taught to the patient.

Turkish laryngospasm practice: in anaesthesia, laryngospasm management is standard knowledge (anaesthesiology + reanimation specialty); paediatric anaesthesia centres have particular expertise. Chronic laryngospasm + PVFM diagnosis + treatment performed in major university hospital ENT + voice surgery/laryngology units coordinated with speech-language therapy. We share patient experiences on our Istanbul ENT services.