Laryngospasm is an involuntary closure of the vocal folds during respiration. Laryngospasm occurs in different settings:
Anesthesia-related laryngospasm occurs during emergence from general anesthesia, when the vocal cords can forcefully come together. This type of laryngospasm is treated with muscle relaxants and sometimes reintubation. Due to the drugs used during surgery, the patient most often does not remember experiencing laryngspasm after the event.
Sleep-related laryngospasm is an involuntary closure of the vocal folds occuring during sleep. The patient awakens with noisy breathing (stridor) and difficulty breathing. This can be quite scary, and can lead to fear of sleep and anxiety. Some patients experience symptoms during the day as well as at nighttime. There is often an associated cough which triggers laryngospasm. There is also a strong association with acid reflux, with acidification of the esophagus or larynx triggering the spasms. In addition, laryngospasm is associated with laryngeal nerve inflammation or damage (neuropathy.) A significant percentage of patients will demonstrate impaired movement of one of the vocal cords. Neuropathy increases the sensitivity of the vocal cords to saliva, mucus, or stomach acid.
Treatment for sleep-related laryngospasm is targeted at control of acid reflux, management of neuropathy, and cough supression. Reflux is managed through medication, dietary modification, and lifestyle changes (timing of meals, weight loss, stress management). In addition, relaxed breathing strategies can be helpful to the patient in order to shorten events of laryngospasm when they occur. Botox injection into the vocal cords (thyroarytenoid muscles) is helpful in many patients through an incompletely understood mechanism, as are drugs used to treat neuropathy including amitriptyline and gabapentin (Neurontin).