Ducasse
Hyperbaric oxygenation was associated with more rapid clinical recovery in non-comatose patients with carbon monoxide poisoning.
Clinical Bottom Line:
1. Early hyperbaric oxygen treatment results in a significant reduction in those with clinical impairment at 2 and 12 hours.
Appraised by: Mike Bennett, Dept. of Diving and Hyperbaric Medicine, Prince of Wales Hospital Sydney; Tuesday, 24 November, 1998
Clinical Scenario: Non-comatose patient with carbon monoxide intoxication and presenting to hospital within 2 hours.
Three-part Question: In non-comatose patients suffering with carbon monoxide intoxication, does the application of hyperbaric oxygen, compared to a normobaric oxygen regime, result in any improvement in neurological outcome?
Search Terms: Hyperbaric oxygenation, carbon monoxide poisoning.
The Study: Single-blinded randomised controlled trial with intention-to-treat. Presenting within 2 hours of exposure, less than 12 hours exposure, Glasgow Coma Score of 12 or more and not pregnant. Control group (N = 13; 13 analysed): Oxygen at 1ATA for 6 hours, then 0.5ATA for 6 hours in the ICU. Experimental group (N = 13; 13 analysed): Oxygen at 2.5ATA for 2 hours in a hyperbaric chamber, then at 1ATA for 4 hours and 0.5ATA for 6 hours.
The Evidence:
Outcome |
Time to Outcome |
NBO group |
HBO group |
Relative risk reduction |
Absolute risk reduction |
Number needed to treat |
Clinical abnormalities |
2 hours |
0.692 |
0.154 |
78% |
0.54 |
2 |
95% CI |
32% to 100% |
0.22 to 0.86 |
1 to 5 | |||
Clinical abnormalities |
12 hours |
0.385 |
0 |
100% |
0.39 |
3 |
95% CI |
0.12 to 0.65 |
2 to 8 |
Comments:1. Patients and staff not blinded to treatment.2. No information on longer-term outcomes. No apparent neurological differences.3. Clinical abnormalities included headache, reflex impairment, asthenia and pulmonary
Expiry date: August 2022
References: 1. Ducasse JL, Cesis P, Marc-Vergnes JP. Non-comatose patients with acute carbon monoxide poisoning: hyperbaric or normobaric oxygenation? Undersea Hyperbaric Medicine 1995;22:9-15.
2. Ducasse JL, Izard PH, Celcis P, Leclercq Ch et al. Moderate carbon monoxide poisoning: hyperbaric or normobaric oxygenation? In: Bakker DJ, Schmutz J eds. Hyperbaric Medicine Proceedings, 2nd Swiss Symposium on Hyperbaric Medicine. Basel, Switzerland: Foundation for Hyperbaric Medicine 1990:289-297.
