Laryngospasm is a sudden, involuntary spasm of the vocal cords that briefly prevents breathing. Despite feeling terrifying in the moment, it is not life-threatening — it resolves within seconds to a minute — and it is highly treatable once correctly diagnosed.
Definition
A spasm is any involuntary contraction of a muscle. The larynx contains multiple muscles all of which can potentially spasm. Laryngospasm specifically refers to sudden forceful adduction (closing) of the vocal folds, obstructing the airway momentarily. It must be distinguished from cricopharyngeal spasm (a lump sensation, not an airway event) and adductor spasmodic dysphonia (a voice disorder, not an airway event).
Symptoms
The symptoms are highly characteristic and almost self-diagnostic:
- Abrupt, sudden onset with no warning
- Can occur at any time — awake or asleep
- Commonly triggered by eating and talking simultaneously, or by something going ‘down the wrong way’
- May awaken a patient from sleep, unable to breathe
- Produces a high-pitched crowing sound (stridor) on attempted inspiration
- Intense sensation of suffocation — feels like it will never end
- Typically lasts 10–60 seconds, then resolves completely
- Leaves the patient shaken but unharmed
Causes
Neurologic Sensitivity
This seems to be the most common cause that I encountered. An individual has had a prior nerve injury, whether or not they were even aware of it, and after the nerve re-grows back to the muscles in the larynx, it is hypersensitive and spontaneously triggered adduction occurs more often.
Post-Extubation
Laryngospasm is well recognized after general anesthesia, particularly when the endotracheal tube is removed while the patient is in a light plane of anesthesia. The irritated larynx is more reactive and the individual less alert to stop it.
Reflux Trigger
Laryngopharyngeal reflux (LPR) is a possible cause. A small amount of acid reaching the larynx might trigger an involuntary protective closing reflex — the same reflex that prevents you from aspirating liquid, now misfiring in response to acid rather than food.
Management
During an Episode
The most important action is to stay calm. Panic worsens the spasm by increasing inspiratory effort. Slow, deliberate nasal breathing — or holding the breath briefly to reduce the urge to gasp — typically allows the spasm to resolve. Swallowing during the episode can also trigger the relaxation reflex.
Medication
For patients with very frequent or disruptive episodes, a low dose of a neuromodulating medication (such as amitriptyline or gabapentin) might reduce laryngeal hyperreactivity.
Botulinum Toxin Injection
In some cases of severe, refractory laryngospasm that does not respond to reflux treatment or neuromodulators, a small injection of botulinum toxin into the thyroarytenoid muscle can dramatically reduce the frequency and severity of episodes.
Prognosis
For intermittent episodes, generally maintaining calm and inspiring slowly will allow episodes to break. If there is an visible hyperreactivity of the LCA muscle, then treating that muscle with intermittent botulinum toxin injection can manage it, but the symptoms will return as it wears off. If the twitchy muscle can be identified and the spasms are frequent, then a permanent cutting and reinnervation of the muscle with a new nerve resolve the problem on a permanent basis.