Carlson
The topical nasal decongestant, oxymetazoline, did not reduce the rate of middle-ear barotrauma in patients having hyperbaric oxygen therapy.
Clinical Bottom Line: 1. No evidence that topical decongestants reduce middle ear barotrauma.
- Appraised by: Mike Bennett, Dept of Diving and Hyperbaric Medicine, Prince of Wales Hospital
Sydney; Thursday, 04 February, 1999
- Clinical Scenario: A patient presents for hyperbaric oxygen therapy. We wondered if topical nasal decongestants would decrease the incidence of aural barotrauma.
- Three-part Question: In patients undergoing hyperbaric oxygen therapy, does the pre-hyperbaric use of topical nasal decongestant compared to no specific pre-treatment, result in less middle ear barotrauma?
- Search Terms: ear, middle, barotrauma, nasal decongestants
- The Study:
Double-blinded concealed randomised controlled trial with intention-to-treat. Adults requiring hyperbaric therapy for acute carbon monoxide poisoning and able to make informed consent. Control group (N = 30; 30 analysed): Two sprays of sterile water into each nostril at least 15 minutes prior to hyperbaric exposure at 2.4 ATA. Experimental group (N = 30; 30 analysed): Two sprays of oxymetazoline hydrochloride into each nostril at least 15 minutes prior to hyperbaric exposure at 2.4 ATA.
- The Evidence:
| Outcome | Water group rate | Oxymet group rate | Relative risk increase | Absolute risk increase | NNH |
| Teed score > zero after treatment | 0.4 | 0.467 | 17% | 0.067 | 15 |
| 95% CI: | -46% to 79% | -0.183to 0.317 | NNH 3 to INF NNT = 5to INF | ||
| Ear pain on compression | 0.2 | 0.300 | 50% | 0.100 | 10 |
| 95% CI: | -59% to 100% | -0.118 to 0.318 | NNH 3 to INF NNT = 8 to INF | ||
| Asymptomatic compression | 0.333 | 0.367 | 10% | -0.034 | 29 |
| 95% CI: | -62% to 83% | -0.207 to 0.275 | NNH 4 to INF NNT = 5 to INF |
- Comments:
1. Well-designed study with 80% power to detect 50% reduction in the incidence of barotrauma. 2. All CO poisoned patients, probably treated in a monoplace chamber. 3. Most patients experienced some discomfort in the ears. 4. Compression rate not specified.
- Expiry date: June 2020
- References: 1. Carlson S, Jones J, Brown M, Hess C. Prevention of hyperbaric-associated middle ear barotrauma. Annals of Emergency Medicine 1992; 21:1468-1471.
