Marci Williams,a 62-year-old woman,had a tympanoplasty 6 weeks ago and has been cleared by her otorhinolaryngologist to undergo a restorative dental procedure in which light anesthesia will be used.The dental procedure was uneventful,but Marci experienced ear pain,nausea and vomiting,and hearing loss in the former operative ear after the dental procedure.What could have been a probable cause of Marci's untoward recovery and hearing loss?

Question

Quizplus · Accepted Answer

Some practitioners believe the use of nitrous oxide as an anesthetic inhalation agent is hazardous to hearing in patients who have undergone previous reconstructive middle ear surgery.During general anesthesia,inhaled nitrous oxide diffuses into the middle ear space through the capillaries of the middle ear mucosa.This results in increased middle ear pressure.Rapid increases in middle ear pressure proportional to inhaled levels of nitrous oxide and abnormal eustachian tube function may cause nausea,vomiting,and rupture of the tympanic membrane in susceptible patients.This includes patients having previous ear surgery,otitis media,sinusitis,upper respiratory tract infections,enlarged adenoids,or other disorders of the nasopharynx.When nitrous oxide is discontinued,the gas is rapidly reabsorbed and strong negative pressure in the middle ear may occur.This negative pressure may result in nausea,vomiting,serous otitis,hemotympanum,disarticulation of the stapes,and impaired hearing.

Marci Williams,a 62-Year-Old Woman,had a Tympanoplasty 6 Weeks Ago and Has