Does the addition of a second daily session of hyperbaric oxygen therapy to intratympanic steroid influence the outcomes of sudden hearing loss?

The aim of this study is to investigate whether, in addition to intratympanic steroid therapy, additional hyperbaric oxygen therapy (HBOT) sessions per day (twice a day for 5 days) is more useful than one session per day for 10 days in patients affected by severe and profound idiopathic sudden sensorineural hearing loss (ISSNHL). A total of 55 patients affected by unilateral severe and profound ISSNHL were recruited. Two protocols were adopted. In the first, 27 patients (13 with profound and 14 with severe hearing loss) underwent one session of HBOT per day for 10 days, 6 days a week. An HBOT session comprised a period of 14 minutes air compression followed by 90 min at 2.4 atm absolute (ATA) followed by a decompression period of 15 min in oxygen. Patients breathed 100% oxygen through an appropriate mask checked for leaks. Patients were given 0.4 ml of 62.5 mg/ml of intratympanic prednisolone during the first three days of the protocol. In the second protocol, 28 patients (10 with profound and 18 with severe hearing loss) received 10 sessions of HBOT, twice a day for five days, 2.4 ATA 90 min 100% oxygen. The intratympanic injections of prednisolone were given between the two sessions of HBOT during the first three days of the protocol. Since there were no significant differences in hearing outcomes between the two protocols, the present study shows that the protocol of two sessions of HBOT per day is a valid treatment and equally effective as the one HBOT session per day, but with shorter treatment time.