Evaluation of Drug Effects on Eustachian Tube Dysfunction in Divers

Problems associated with the Eustachian Tube (ET) can result in significant impacts to diving, aviation forces, and hyperbaric medicine. Eustachian tube dysfunction (ETD) is associated with middle-ear barotraumas, which is one of the most prevalent medical complications in the above arenas. The purpose of this trial was to determine the efficacy of various drugs to decrease the incidence of ETD. Acetylcysteine, surfactant, pseudoephedrine, and oxymetazoline were tested against nasal saline mist in a subject-blinded, randomized trial. Divers were administered the drugs just prior to repetitive bounce dives while breathing oxygen or air in separate trials. Effectiveness was assessed via subjective difficulty to clear (holds on descent), ET opening pressures, and measurements elicited from a nine-step inflation/deflation tympanogram. There was considerable variability in the outcomes of each analysis that resulted in no consistent differences being established between the drugs evaluated. No drug had evidence to support recommendations for or against its use in preventing ETD. While the results of this study failed to demonstrate efficacy for any given medication, some of the drugs tested may yet show beneficence if evaluated in another experiment designed to address the confounding factors encountered during this study.