Otic barotrauma is ear pain or damage to the tympanic membrane caused by rapid changes in environmental pressure.
To maintain equal pressure on both sides of the tympanic membrane, gas (air) must be able to move freely between the nasopharynx and middle ear (1). When an upper respiratory infection, allergy, or other mechanism interferes with eustachian tube function during changes in environmental pressure, the pressure in the middle ear either falls below ambient pressure, causing retraction of the tympanic membrane, or rises above it, causing bulging. With negative middle ear pressure, a transudate of fluid may form in the middle ear. As the pressure differential increases, ecchymosis and subepithelial hematoma may develop in the mucous membrane of the middle ear and the tympanic membrane. A very large pressure differential may cause bleeding into the middle ear, tympanic membrane rupture, and the development of a perilymph fistula through the oval or round window of the inner ear.
Causes of barotrauma to the ear include a sudden or rapid change in external environmental pressure, such as an explosion (blast injury), rapid ascent (eg, during scuba diving) or descent (eg, during air travel or sky diving). Sensorineural hearing loss or vertigo during descent suggests the development of a perilymph fistula; the same symptoms during ascent from a deep-sea dive can suggest an air bubble formation in the inner ear.
Symptoms of otic barotrauma are aural fullness, severe pain, conductive hearing loss, and, if there is a perilymph fistula, sensorineural hearing loss and/or vertigo.
Patients who have pre-existing eustachian tube dysfunction and undergo hyperbaric oxygen therapy or who are unable to perform middle ear equalization maneuvers (eg, intubated patients) are at high risk for otic barotrauma.
General reference
1. Sadé J, Ar A. Middle ear and auditory tube: middle ear clearance, gas exchange, and pressure regulation. Otolaryngol Head Neck Surg. 1997;116(4):499-524. doi:10.1016/S0194-59989770302-4
Diagnosis of Otic Barotrauma
Primarily history and physical examination
Imaging (CT, MRI) to identify complications
Diagnosis of ear barotrauma is primarily clinical, established by a history of recent exposure to environmental pressure changes coupled with the abrupt onset of characteristic symptoms. Otoscopy may reveal findings ranging from congestion and vascular injection along the manubrium to severe retraction or bulging, hemotympanum, and perforation. Several grading scales are available for clinicians to classify the extent of barotrauma (eg, Teed Classification, O'Neill Grading System). The Teed (or Modified Teed) classification is one of the most widely used and assigns grades 0 to 5 based on otoscopic findings.
This photo shows barotrauma inside the ear with visible bruising of the superior and central aspect of the external ear canal. The tympanic membrane is intact.
PROFESSOR TONY WRIGHT, INSTITUTE OF LARYNGOLOGY & OTOLOGY/SCIENCE PHOTO LIBRARY
Patients with persistent and intense vertigo, sensorineural hearing loss, or severe tinnitus should undergo urgent audiometry and prompt referral to otolaryngology to exclude severe complications related to inner ear trauma such as labyrinthine window rupture.
Imaging (eg, CT, MRI) is reserved for identifying suspected complications such as labyrinthine fistulae or perilymphatic fistulas.
Treatment of Otic Barotrauma
Methods to equalize pressure (eg, yawning, swallowing, chewing gum)
Routine self-treatment of pain caused by changing pressure in an aircraft includes chewing gum, attempting to yawn and swallow, blowing against closed nostrils, and using decongestant nasal sprays. If pain is severe and hearing loss is conductive, myringotomy may help.
If hearing loss is sensorineural and vertigo is present, a perilymphatic fistula is suspected and middle ear exploration to close a fistula should be considered, although this is a very rare entity.
Prevention of Otic Barotrauma
A person with nasal congestion due to an upper respiratory infection or allergies should avoid flying and diving. When these activities are unavoidable, a topical nasal vasoconstrictor (eg, phenylephrine, oxymetazoline) is applied 30 to 60 minutes before descent and ascent.
Tympanostomy tubes placed prophylactically prevent otic barotrauma for patients who have known eustachian tube dysfunction and are undergoing hyperbaric oxygen therapy. Tube placement is also reasonable for patients with ear pressure after their first hyperbaric dive; such patients may have occult eustachian tube dysfunction or dysfunction only in certain situations (eg, only during hyperbaric oxygen treatment but not during an airplane flight).
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