Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 8-04: Diseases of the Eustachian Tube + Key Features Download Section PDF Listen +++ ++ Persons with poor eustachian tube function (eg, congenital narrowness or acquired mucosal edema) may be unable to equalize the barometric stress exerted on the middle ear by air travel, rapid altitudinal change, or underwater diving During airplane descent, the negative middle ear pressure tends to collapse and block the eustachian tube, causing pain Underwater diving may represent an even a greater barometric stress to the ear than flying During the descent phase of the dive, if inflation of the middle ear via the eustachian tube has not occurred, pain will develop within the first 15 feet; the dive must be aborted Tympanic membrane perforation is an absolute contraindication to diving because the patient will experience an unbalanced thermal stimulus to the semicircular canals and may experience vertigo, disorientation, and even emesis + Clinical Findings Download Section PDF Listen +++ ++ Hemorrhage (hemotympanum) or perilymphatic fistula May result from severely negative pressures in the tympanum in divers In the perilymphatic fistula, the oval or round window may rupture, resulting in sensory hearing loss and acute vertigo Emesis due to acute labyrinthine dysfunction can be very dangerous during an underwater dive Sensory hearing loss or vertigo, which develops during the ascent phase of a saturation dive, may be the first (or only) symptom of decompression sickness Patients should be warned to avoid diving when they have upper respiratory infections or episodes of nasal allergy + Diagnosis Download Section PDF Listen +++ ++ Clinical diagnosis based on symptoms in a patient who has recently undergone recent increase or decrease in ambient pressure + Treatment Download Section PDF Listen +++ ++ During airplane descent, Advise the patient to swallow, yawn, and autoinflate frequently Oral decongestants (eg, pseudoephedrine, 60–120 mg) should be taken several hours before anticipated arrival time so that they will be maximally effective during descent Topical decongestants such as 1% phenylephrine nasal spray should be administered 1 hour before arrival For acute negative middle ear pressure that persists on the ground, treatment includes decongestants and attempts at autoinflation Myringotomy (creation of a small eardrum perforation) provides immediate relief and is appropriate in the setting of severe otalgia and hearing loss Repeated episodes of barotrauma in persons who must fly frequently may be alleviated by insertion of ventilating tubes For divers, immediate recompression will return intravascular gas bubbles to solution and restore the inner ear microcirculation