Acute acoustic trauma: how to manage and how to prevent?

INTRODUCTION: The consequence of an exposure to intense sounds can be a temporary or permanent hearing loss and even with a rapid therapeutic management, severe sensorineural sequelae may persist.

METHODS: the authors report a retrospective study about 64 patients followed for an acute acoustic trauma during a period of 8 years (2006 to 2013). For all the cases, a clinical examination associated to a pure-tone audiometry was conducted. Hearing levels were measured at the frequencies 500, 1000, 2000 and 3000 Hertz. Auditory evoked potentials were performed in 17 cases. The therapeutic and evolutive data were detailed and discussed.

RESULTS: All our patients were male with a mean age of 34 years. The cause of acoustic trauma was a firing of a gun near the ear in 48 cases, an explosion near the ear in 5 cases and a sudden exposure to loud noises near military planes in 11 cases. Clinical complaints were acute hearing loss with tinnitus. Audiometric exams found a sensorineural hearing loss with a hearing level average of 38 decibels (dB) +/- 14 SD. The therapy consisted of systemic cortisteroids associated in all the cases to peripheral vasodilators.  It was given intravenously during 10 days and then orally with vasodilators during one to 3 months. Hyperbaric oxygenotherapy have been administrated for 25 patients. The follow-up consisted of questioning about symptoms, clinical examination and pure-tone audiometry. A good evolution was noted in 52 cases (81%) and the mean of hearing level after therapy was: 24 dB +/- 12 dB. Despite a prolonged therapy with vaso-active drugs, tinnitus persisted in 36 cases.

CONCLUSION: Controlling noise and its harmful effects through technical devices and safety professionals programs are the best way to reduce the frequency and the sensorineural sequelae due to acute acoustic trauma.