Middle ear pressure changes during different inhalation anesthesia comparative study by tympanometry between modern and old inhalational anesthetic agents

This investigation examined the effect of modern inhalant anesthesia [isoflurane and sevoflurane] in comparison with older inhalational agent [halothane] with or without nitrous oxide on middle ear pressure [MEP]. Tympanometry was used to measure MEP variations. Seventy-six subjects were examined with tympanometry prior to inhalant anesthesia and baseline tympanometry was performed. This study found that the changes of MEP are significantly greater when nitrous oxide added to any of modern or older inhalational agents. The results have shown that administration of nitrous oxide with these agents should be used with great care during tympanic membrane grafting, ossiculoplasty or ossicular replacement prosthesis