Kayser
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
