Mutzbauer3
Some weak evidence that vitamin C and E ingestion before hyperbaric oxygen may reduce the drop in erythropoietin plasma concentrations in divers.
Clinical Bottom Line:
|
1. No important difference between groups demonstrated, but there was a greater in-group fall in EPO in the placebo divers. |
Citation/s:1. Mutzbauer TS, Schneider M, Neubauer B, Weiss M, Tetzlaff K. Antioxidants may Attenuate Plasma Erythropoietin Decline after Hyperbaric Oxygen Diving. International journal of sports medicine. 2015 Nov;36(13):1035-40.
Lead author's name and fax: Till Mutzbauer mutzbauer@gmail.com
Three-part Clinical Question:For those exposed to hyperbaric oxygen during in-water diving, does the administration of antioxidants during exposure result in maintenance of plasma erythropoietin?
Search Terms: Erythropoietin; antioxidants; adverse effects
The Study:
Double-blinded concealed randomised controlled trial with intention-to-treat.
The Study Patients: Healthy volunteer divers.
Control group (N = 8 ; 8 analysed): Placebo medication three hours prior to three dives to 4 msw (1.4 ATA) breathing 100% oxygen on successive days.
Experimental group (N = 8 ; 8 analysed): As above but active antioxidants: 1g of ascorbic acid combined with 600 IU d- a -tocopherol three hours before each exposure.
The Evidence:
Measure |
Placebo Group |
HBO Group |
Difference |
95% CI | ||
Mean |
SD |
Mean |
SD | |||
|
Plasma erythropoietin after third dive (mIU/ml) |
5.1 |
1.4 |
5.5 |
1.4 |
-0.40 |
-2.5 to 1.7 |
|
Plasma EPO as proportion of starting value day 1 (%) |
72.3 |
28.1 |
81.5 |
28.1 |
-9.2 |
-856 to 837 |
Comments:
1. Small study underpowered to detect a potentially important difference between groups. Main results in the paper compared within group differences. No sample size calculation reported.
2. Results suggest a trend decline in EPO plasma levels over a period of 3 days HBO exposure but no statistically important differences between groups. Reduced EPO may mean a reduction in endogenous antioxidant mechanisms.
Appraised by:Mike Bennett m.bennett@unsw.edu.au; Saturday, 18 September 2021
Kill or Update By: September 2026
