A 23-year-old man presented to an American outpatient clinic with complaints of pain when swallowing and hoarseness for two days. The symptoms began immediately after he inhaled nitrous oxide, also known as laughing gas, through his mouth from a container. On examination, redness, swelling, and detachment of the mucous membrane of the soft palate and uvula, as well as the posterior wall of the oropharynx, were detected. There was no straining or stridor in breathing. Nasolaryngoscopy revealed ulceration and swelling of the right vocal cord. Doctors Michael Patrizio and Meredith Hayden of the University of Virginia shared the case in The New England Journal of Medicine.
Based on the history and examination, the man was diagnosed with frostbite of the soft palate, pharynx, and larynx due to inhalation of nitrous oxide. This gas is used for anesthesia and may be used for non-medical purposes. It is stored in pressurized cylinders as a liquid, and due to evaporation and expansion upon sudden release, the gas and cylinder rapidly cool, which can lead to contact frostbite. The patient was prescribed over-the-counter analgesics, lidocaine anesthetic gel, and the glucocorticoid triamcinolone topical. He failed to return for follow-up.
