No lasting benefit from pressurization following rapid mountain ascent
Clinical Bottom Line:
1. Short-term relief of symptoms while compressed.
2. No longer term benefit from single compression
Citation:
Kayser B, Jean D, Herry JP. Pressurization and Acute Mountain Sickness,
Aviation Space and Environmental Medicine, 1993;64 (10): 928-37
Three-part Clinical Question:
In healthy young persons making a rapid mountain ascent, does treatment with air
pressurization for three hours, compared with no treatment, reduce the symptoms
of acute mountain sickness.
Search Terms: Acute Mountain Sickness, Hyperbaric
The Study:
Non-blinded randomised controlled trial with intention-to-treat.
Study Patients: Young adult
mountain climbers following a rapid ascent.
Control group: (N = ;
analysed): Rest
Experimental group: (N = ;
analysed): Pressurisation for three hours breathing air at 200mBar above
ambient, starting 1 hour after arrival at altitude
The Evidence:
| Outcome | Time to outcome |
Rest group |
Pressurised group |
P-value for difference |
| AMS score |
1
hr (pre-press) |
2.4
+/- 0.4 |
2.4
+/- 0.4 |
>0.05 |
|
AMS score |
4
hrs (post-press) |
2.4
+/- 0.4 |
0.9
+/- 0.3 |
<0.05 |
|
AMS score |
13
hrs |
6.2
+/- 0.7 |
5.7
+/- 0.6 |
>0.05 |
Comments:
1. AMS scores reflect mild disease only at all measures.
2. Some individuals had symptoms and others did not.
3. Actual numbers not reported.
Appraised by: Berend Stoutenbeek, Matthijs Somford; Thursday, July
03, 2003
Email: bm_stoutenbeek@hotmail.com
Kill or Update By: November 2005