Hoffman3
No evidence of efficacy for hyperbaric oxygen in acute hearing loss or tinnitus of long-standing.
Clinical Bottom Line: 1.No evidence of improvement in hearing loss or tinnitus with the administration of hyperbaric oxygen. 2.Pressurization was associated with some benefit in both groups.
- Appraised by: Mike Bennett, Dept. of Diving and Hyperbaric Medicine, Prince of Wales Hospital
Sydney; Wednesday, 28 July 1999
- Clinical Scenario: A patient with long-standing hearing loss and tinnitus presented for treatment and we wondered if there was any place for hyperbaric oxygen.
- Three-part Question: For patients with hearing loss and/or tinnitus of acute onset, where the loss is of long standing (>6 months), does the application of hyperbaric oxygen, compared to placebo, result in any improvement in hearing loss or tinnitus?
- Search Terms: Hyperbaric oxygen, deafness, tinnitus
- The Study:
Double-blinded randomised controlled trial with intention-to-treat. Patients with a history of sudden onset of inner-ear hearing loss and/or tinnitus lasting at least 6 months. Control group (N = 22; 22 analysed): Air breathing at 1.5ATA for 45 minutes daily, five days each week for 3 weeks. Experimental group (N = 22; 22 analysed): 100% oxygen breathing at 1.5ATA on the same schedule as controls.
- The Evidence:
| Outcome | Time to Outcome | Control group | HBO group | Relative risk reduction | Absolute risk reduction | NNT |
| Improved hearing | 3 weeks | 0.5 | 0.33 | 34% | 0.17 | 6 |
| 95% CI: | -23% to 91% | -0.12 to 0.46 | NNT2 to INF NNH=9 to INF | |||
| Improved tinnitus | 3 weeks | 0.41 | 0.18 | 56% | 0.23 | 4 |
| 95% CI: | -8% to 100% | -0.03 to 0.49 | NNT2 to INF NNH=32 to INF |
Comments: 1. Control group was pressurized and breathed an increased PO2. Any benefit may be due to a placebo effect, pressure effect or oxygen effect (equivalent 31.5% oxygen at 1ATA). 2. All patients received a second course of hyperbaric oxygen at 1.5ATA immediately following the trial course, making longer-term follow-up impossible. 3. 15 treatments may have been insufficient in this chronic, well-established condition.
- Expiry date: June 2020
- References:
1. Hoffmann G, Bohmer D, Desloovere C. Hyperbaric oxygen as a treatment of chronic forms of inner ear hearing loss and tinnitus.In: Wen-ren Li. Proceedings of the Eleventh International Congress of Hyperbaric Medicine, Fuzhou, China. Best Publishing, Flagstaff, Arizona 1993:141-145.
