Otitic barotrauma

Abstract Otitic barotrauma occurs upon descent in individuals with a nasopharyngitis, a large nasopharyngeal lymphoid mass, and for no apparent reason. A Surface Active Membrane (S.A.M.) was found lining the eustachian tube with surface tension lowering properties similar to pulmonary surfactant (S.A.M.). Eustachian S.A.M. allows the lumenal surface of the tube to separate in response to the pull of the musculature. S.A.M. is destroyed by proteolytic enzyme producing bacteria and pulmonary S.A.M. is reduced in cigarette smokers. Reduced or absent eustachian S.A.M. will not allow the lumenal surfaces to separate and pressure equalization to take place. Otitic barotrauma occurs when there is insufficient eustachian S.A.M. resulting in an inability to allow transmission of air from the nasopharynx to the middle ear during descent. A lecithin aerosol used as an effective treatment of hyaline membrane disease (absent S.A.M.) of the newborn may treat or prevent otitic barotrauma. 4