Inner and middle ear hyperbaric oxygen-induced barotrauma.

Patients receiving hyperbaric oxygen (HBO) therapy can sustain inner and middle ear barotrauma. The purpose of this study is to define the incidence and significance of HBO-related barotrauma, in addition to establishing guidelines for prophylactic myringotomy or tympanostomy tube placement. Thirty patients were stratified into two groups (those able to autoinflate and those unable to autoinflate the middle ear) and barotrauma was assessed by otoscopy, tympanometry, high-frequency audiometry, and distortion product otoacoustic emission (DPOAE) testing. Ten of 11 patients (91%) from the noninflater group suffered middle ear barotrauma, and seven of 19 patients (37%) from the autoinflater group sustained middle ear barotrauma. Patients unable to autoinflate the middle ear were shown to have a higher incidence and greater severity of barotrauma than patients able to autoinflate. Pretreatment pressure-equalizing tubes or myringotomies should be considered for patients undergoing HBO therapy who have an artificial airway or have eustachian tube dysfunction and have failed conservative medical intervention. A significant change in DPOAEs (loss of emissions over a 1-kHz range) was found in four of 15 autoinflaters (27%) and two of seven noninflaters (29%). There was no significant difference between the groups. The decrease in DPOAEs was not associated with a change in conventional audiometry.