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Laryngospasm + Bronchospasm — OR Algorithm
TEXTCrisis Management · 6 min read
The two airway emergencies that happen on the wrong side of induction or emergence. One closes the glottis, the other closes the small airways — both desaturate fast.
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3 min read6 sectionsLaryngospasm — pathophysiology + trigger windows
- light anesthesia at extubation or induction
- blood/secretions/vomit on the cords
- surgical stimulation during light planes (especially anal/cervical dilation, peritoneal traction)
- foreign-body sensation
- pediatric airway surgery
- URI within 2-4 weeks
- secondhand smoke exposure
- second-stage anesthesia (Guedel's excitement phase)
Pediatric incidence ~1% overall, up to 10% in active URI.
- silent chest with chest-wall + diaphragm effort
- rocking abdomen
- paradoxical breathing
- tracheal tug
- rapidly falling SpO₂
Laryngospasm — Larson's maneuver + algorithm
The combination of pain + anterior mandibular displacement breaks most partial spasms.
15-20 cmH₂O with 100% O₂ via tight mask.0.5-1 mg/kg IV.0.1-0.5 mg/kg IV, or 4 mg/kg IM (max 200 mg) if no IV — typical peds rescue dose.Atropine 0.02 mg/kg with IM sux in children to blunt bradycardia.
Re-intubate if cords don't open.
Laryngospasm — prevention + post-event care
Deep extubation contraindicated in difficult airway, full stomach, aspiration risk.
Suction before emergence, not during.
Lidocaine 1-1.5 mg/kg IV 1-2 minutes before extubation blunts airway reflexes.
After a laryngospasm episode: rule out negative-pressure pulmonary edema (forced inspiration against closed glottis strongly negative intrathoracic pressure pulmonary capillary leak).
Watch SpO₂ + pink frothy sputum for the next 1-2 hr; treat with O₂ + CPAP + diuresis if symptomatic.
Bronchospasm — recognition under anesthesia
Wheeze on auscultation (may be absent in severe spasm — silent chest), increased peak inspiratory pressure with stable plateau (resistance, not compliance), slow upsloping shark-fin ETCO₂ waveform, hypoxemia, hypercarbia.
- asthma history
- recent URI
- smoking
- COPD
- allergic reaction (consider anaphylaxis differential)
- endobronchial intubation
- light anesthesia with airway stimulation
- drug triggers (β-blockers, NSAIDs in aspirin-sensitive asthma, histamine releasers like morphine + atracurium)
Mainstem intubation must be excluded by re-checking tube depth + bilateral breath sounds before treating bronchospasm.
Bronchospasm — algorithm + volatile choice
Deepen with volatile — sevoflurane + isoflurane are most bronchodilatory; DESFLURANE worsens reactive airways and should be replaced.
Inhaled β₂ agonist: albuterol 4-8 puffs MDI via inline adapter in the circuit (high doses needed because most drug is lost in tubing).
IV epinephrine 10-100 mcg bolus titrated for severe; epinephrine infusion 0.02-0.1 mcg/kg/min for refractory.
Magnesium sulfate 2 g IV over 20 min as smooth-muscle adjunct.
Ketamine 0.5-1 mg/kg IV for refractory bronchospasm — sympathomimetic + bronchodilator + maintains airway reflexes.
Hydrocortisone 100 mg IV for ongoing reactive component.
Rule out anaphylaxis if hypotension or rash accompanies wheeze — manage with full anaphylaxis protocol.
Ventilator settings during bronchospasm
Slow respiratory rate (8-10 breaths/min) + prolonged expiratory time (I:E 1:3 to 1:5) + low tidal volume (6-8 mL/kg PBW) to avoid breath-stacking + auto-PEEP + barotrauma.
Watch the expiratory flow waveform — flow must reach zero before the next breath.
If breath-stacking is occurring, disconnect briefly to allow exhalation, then resume with longer expiratory time.
PEEP is controversial in active bronchospasm — low PEEP (5 cmH₂O) is reasonable; high PEEP risks barotrauma.
Heliox (70:30 He:O₂) reduces turbulent flow in narrowed airways for refractory cases when FiO₂ tolerates dilution.
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