Gasier
Oxygen breathing at 2 ATA did not induce lipid peroxidation, nor any changes in antioxidant activity or nitric oxide levels in plasma
|
1. No important changes in lipid peroxidation, antioxidant enzyme activity or production of nitric oxide following an exposure to hyperbaric oxygen |
Citation/s:1. Gasier HG, Fothergill DM. Oxidative stress, antioxidant defenses and nitric oxide production following hyperoxic exposures. Undersea & hyperbaric medicine: journal of the Undersea and Hyperbaric Medical Society, Inc. 2012 Dec;40(2):125-34
Lead author's name and fax: Dr. Heath G. Gasier – heath.gasier@med.navy.mil
Three-part Clinical Question:For divers, does an increase in inspired oxygen partial pressure result in increased evidence of lipid peroxidation, antioxidant enzyme activity or nitric oxide production?
Search Terms: oxygen toxicity; peroxidation, antioxidant
The Study:Non-blinded randomised controlled trial with intention-to-treat.
The Study Patients: Healthy male divers
Control group (N = 12; 12 analysed): 100% oxygen breathing at 1 ATA in a dry chamber for 120 minutes
Experimental group (N = 12; 12 analysed): As above but at 2 ATA
The Evidence:
Measure |
1 ATA Group |
2 ATA Group |
Difference |
95% CI | ||
Mean |
SD |
Mean |
SD | |||
|
Thiobarbituric acid reactive substances in plasma (microM)at 1 hour |
10.9 |
3.2 |
10.5 |
3.0 |
0.40 |
-7.8 to 8.6 |
|
Plasma superoxide dismutase activity (U/ml) at 1 hour |
12.7 |
4.3 |
12.8 |
3.1 |
-0.10 |
-12.0 to 11.8 |
|
Plasma nitrite levels mocromol/L) at 1 hour |
89 |
37 |
101 |
55 |
-12 |
-1872.215 to 848.2 |
Comments:
1. Diet was controlled over the course of the experiment
2. Subjects acted as their own controls with order of exposure selected at random.
3. Three exposures - 1 ATA, 1.5 ATA and 2 ATA
4. Lack of any clear dose-related effect may be due to insufficient pressure and oxygen exposure.
Appraised by: Mike Bennett m.bennett@unsw.edu.au ; Monday, 22 June 2020
Kill or Update By: June 2024
