Schwab
No evidence of improvement in hearing loss or tinnitus with hyperbaric oxygen compared to a regime of hydroxyethyl starch and pentoxifylline.
Clinical Bottom Line: 1. No statistically significant improvement in hearing loss or tinnitus was demonstrated in this trial. 2. There was a trend to more improvement in hearing loss in the hyperbaric group
- Appraised by: Mike Bennett, Department of Diving and Hyperbaric Medicine, Prince of Wales Hospital, Sydney Thursday, 11 November 1999
- Clinical Scenario: A patient with sudden loss of hearing and tinnitus of unknown cause presented for treatment.
- Three-part Question: For patients presenting for treatment of acute hearing loss and or tinnitus, does administration of hyperbaric oxygen, compared to pentoxifylline and hydroxyethyl starch, result in any improvement in either complaint?
- Search Terms: Hyperbaric oxygenation, sudden hearing loss, tinnitus
- The Study:
Non-blinded randomised controlled trial with intention-to-treat. Sudden hearing loss with at least 20dB loss in one or more frequencies and /or tinnitus, seen within 2 weeks and without any prior therapy. Control group (N = 38; 31 analysed): Intravenous hydroxyethyl starch 6% 250mls and pentoxyphylline 300mg daily for ten days. Experimental group (N = 37; 24 analysed): 100% oxygen at 2.5ATA for 75 minutes daily for 10 days.
- The Evidence:
| Non-event outcomes | Time to outcome | Control group | HBO group | P-value |
| Mean hearing change (dB) | ?4 weeks | 10.7 | 15.6 | NS |
| Tinnitus rating (0 to 10 scale) | ?4 weeks | 4.0 | 3.6 | NS |
- Comments:
1. There may be a significant clinical benefit in hearing recovery with hyperbaric oxygen, however, this trial is of insufficient power to confirm this. 2. The numbers reaching follow-up are unclear. 3. There is no placebo control to establish the rate of spontaneous improvement.
- Expiry date: June 2020
- References:
1. Schwab B, Flunkert C, Heermann R, Lenarz T. HBO in the therapy of cochlear dysfunctions - first results of a randomized study. Collected manuscripts of XXIV Annual Scientific Meeting of the European Underwater and Baromedical Society, M Gennser, ed. Stockholm 1998; 40-42.
