[Effect of nitrous oxide inhalation anesthesia on sero-mucous secretions of the tympanum].

It is known that nitrous oxide anaesthesia results in an increase of the middle ear pressure. The aim of this project was to find out, if an increase of the middle ear pressure due to high concentration of nitrous oxide could lead to evacuation of the seromucoid secretion through the Eustachian tube. In 37 children (64 ears) scheduled for myringotomy, tympanograms were performed immediately before and during anaesthesia, the middle ear fluid was confirmed by myringotomy and, if any, sucked out. Both the comparison of the tympanograms prior and during the anaesthesia and the results of myringotomy led to a conclusion, that, in general, nitrous oxide anaesthesia induces no evacuation of middle ear fluid via the Eustachian tube.