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Write a short note on Laryngospasm.

General Surgery · Final Professional

Definition & Cause

Laryngospasm is a reflex, involuntary sustained closure of the vocal cords (spasm of the laryngeal muscles) that partially or completely obstructs the airway. It is provoked by stimulation of the airway — by secretions, blood, vomit, an airway device or surgical stimulus — while anaesthesia is too light, classically at induction or emergence (stage II).

Features & Management

It presents with stridor (partial) or complete airway obstruction with paradoxical (see-saw) chest/abdominal movement and falling oxygen saturation; if unrelieved it causes hypoxia, bradycardia and cardiac arrest. Management, in order: remove the stimulus and any secretions (suction), apply 100% oxygen with continuous positive airway pressure and a firm jaw thrust, deepen anaesthesia (e.g. Propofol), and if spasm persists give a small dose of suxamethonium (± atropine for bradycardia) and ventilate.

CLINICAL PEARL

The classic first-line for laryngospasm is 100% O₂, CPAP and jaw thrust (‘Larson’s point’ pressure behind the ear lobes may help), progressing to deepening anaesthesia and then suxamethonium if it does not break.

DANGER / REMEMBER

Watch for negative-pressure pulmonary oedema after a severe laryngospasm — forced inspiration against a closed glottis generates very negative intrathoracic pressure that draws fluid into the alveoli, causing post-obstruction pulmonary oedema.

Prevention

Because laryngospasm is triggered by airway stimulation during light anaesthesia, prevention centres on avoiding such stimulation at vulnerable moments: clearing secretions and blood before they reach the cords, not inserting airways or extubating in the light ‘stage II’ plane, and either keeping the patient adequately deep or waiting until they are fully awake. It is commoner in children, in smokers and after upper-airway surgery, so extra vigilance is warranted in these groups.

CLINICAL PEARL

The stepwise treatment to memorise is 100% oxygen, CPAP and jaw thrust → deepen anaesthesia → suxamethonium if it persists — and prevention lies in not stimulating the airway during the light stage-II plane.

100% oxygen, jaw thrust, deepen anaesthesia; suxamethonium if persistent.

KEY POINT

Key points TO remember

Reflex sustained vocal-cord closure from airway stimulation during light anaesthesia (stage II).
Stridor/obstruction, see-saw breathing, desaturation → hypoxia & bradycardia if unrelieved.
Treat: remove stimulus/suction, 100% O₂ + CPAP + jaw thrust, deepen, suxamethonium if persistent.
Beware negative-pressure pulmonary oedema afterwards.

EXAM TIP

Sources: Morgan & Mikhail’s Clinical Anesthesiology; Miller’s Anesthesia; Ajay Yadav’s Short Textbook of Anaesthesia.

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