What Researchers Did
Researchers investigated how Eustachian tube function and middle ear barotrauma were affected by exposure to high or low atmospheric pressures in 90 healthy adults.
What They Found
After hypobaric exposure, 17.5% of ears (14 out of 80) developed middle ear barotrauma, while 34% of ears (34 out of 100) developed it after hyperbaric exposure. Eustachian tube dysfunction, characterized by altered opening capacity, was more common after extreme pressure exposure, and patients with worse pre-existing function were more prone to barotrauma. While function improved over the first two hours after the first HBO treatment, it worsened overall after the seventh treatment.
Canadian Relevance
This study addresses middle ear barotrauma, a common side effect associated with hyperbaric oxygen therapy (HBOT). HBOT is a Health Canada-recognized treatment for several conditions, including delayed radiation injury, diabetic foot ulcers, carbon monoxide poisoning, decompression sickness, arterial gas embolism, osteoradionecrosis, radiation cystitis, and radiation proctitis.
Study Limitations
A limitation is that this study was published in 1996, meaning diagnostic techniques for Eustachian tube function may have advanced significantly since then.