Chloral hydrate and middle ear pressure

Middle ear pressure and tympanic membrane compliance were measured in 34 infants and young children (66 ears) with normal middle ears under oral choral hydrate hypnosis. Tympanograms were performed before and 40 to 60 minutes after administration of the drug. Results showed that the middle ear pressure increased significantly in all cases and in both sexes. This increase ranged between +19 and +219 mm H2O. In all cases the pressure returned to its prehypnotic values after recovery. Results of tympanic membrane compliance showed significant increase in males and not significant decrease in females.