Therapeutic Effects of Carbogen Therapy in Sudden Sensorineural Hearing Loss

Abstract

BACKGROUND Sudden Hearing Loss (SHL) is a rare disease accounting for 1% of all sensorineural hearing loss cases, but it is considered an otological emergency. The sooner the treatment begins, the outcome proves to be better. Different theories have been postulated with regard to determining its cause. Most accepted treatment at the present time is systemic steroid therapy. The purpose of our study was to compare the efficacy of carbogen therapy combined with steroids, is whether or not superior to steroids alone in the treatment of sudden hearing loss. MATERIALS AND METHODS This prospective, non-randomised, controlled parallel trial included 60 patients with idiopathic SHL who visited our clinic within 14 days of symptom onset between August 2013 and February 2015. All patients received oral prednisolone for 10 days. Of the 60 patients, 30 received no additional treatment and 30 received additional carbogen inhalation. Hearing improvement was measured using Siegel's criteria. RESULTS We observed in our study that complete recovery at two months occurred in 33.33% and 26.67% subjects in Group 1 [Carbogen therapy plus steroids] and Group 2 [steroids alone] correspondingly. As for partial recovery, 53.33% and 66.67% in Group 1 and 2 correspondingly (Siegel's criteria 1 and 2). Slight improvement was noticed as follows at 10 th sitting 23.33% and 13.33% and at 2 months 13.33% and 6.67% in corresponding group. Though these results show that carbogen therapy is better than steroids, the data is calculated to be statistically insignificant using Fisher's exact test (p-value 0.267 and 0.591 > 0.05). We also found that there is statistically significant [p-value 0.01] association between age of onset of sensorineural hearing loss and betterment of hearing. Younger the age at the time of onset of hearing loss, there are better chances of hearing gain towards normal hearing sensitivity. CONCLUSION Carbogen inhalation added to steroids was a more effective treatment than steroids alone in patients with idiopathic sudden sensorineural hearing loss.