Schwab
No evidence of improvement in hearing loss or tinnitus with hyperbaric oxygen compared to a regimen 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
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.
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.
Appraised by:Mike Bennett, Department of Diving and Hyperbaric Medicine, Prince of Wales Hospital, Sydney Thursday, 11 November 1999
Expiry date:June 2020
