Acute Mountain Sickness (AMS)
Conditions
Brief summary
This pilot study aims to evaluate the efficacy of positive expiratory pressure (PEP) therapy at 10 cmH₂O in improving peripheral oxygen saturation (SpO₂) and mitigating symptoms of acute mountain sickness (AMS) in healthy individuals exposed to extreme altitude conditions. Three male participants will be monitored during an ascent of Mount Aconcagua, Argentina, at elevations of 4,300 m, 5,560 m, and 6,000 m above sea level. The study involves three sequential phases of 10 minutes each: baseline breathing without PEP, breathing with PEP applied via a mechanical face mask, and post-PEP breathing. Primary outcomes include changes in SpO₂ and Lake Louise Score (LLS) to assess AMS severity. Findings will provide preliminary data on the potential role of PEP as a non-pharmacological intervention in high-altitude medicine.
Interventions
The intervention under investigation will be the application of positive expiratory pressure (PEP) at 10 cmH₂O using an Ambu mask. The mask will allow participants to inspire freely while generating a controlled expiratory pressure. The PEP device is a non-pharmacological medical device whose uses in both hospital and pre-hospital settings are part of everyday medical practice.
Sponsors
Study design
Eligibility
Inclusion criteria
* Healthy volunteers without ongoing medical conditions * Over 18 years of age * Volunteers with the physical and technical skills necessary to undertake a mountaineering expedition on Mount Aconcagua, Argentina, and with previous experience at extreme altitudes
Exclusion criteria
* Subjects with any ongoing medical conditions * Under 18 years of age * Subjects without previous mountaineering experience at extreme altitudes and without adequate physical and technical preparation necessary to undertake a mountaineering expedition on Mount Aconcagua, Argentina
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Peripheral Oxygen Saturation (SpO2) | During the 3 weeks of expedition on Mount Aconcagua, after arrival of participants at 4300masl, 5560masl and 6000 masl. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Lake Louise Score | During the 3 weeks of expedition on Mount Aconcagua, after arrival of participants at 4300masl, 5560masl and 6000 masl. | The Lake Louise Score (LLS) is a standardized tool to diagnose Acute Mountain Sickness (AMS). It combines self-reported symptoms (headache, gastrointestinal upset, fatigue/weakness, dizziness/lightheadedness) rated from 0 (none) to 3 (severe). AMS is diagnosed when headache is present plus at least one other symptom, with a total score ≥3. Higher scores reflect greater symptom severity: 3-5 mild AMS, 6-9 moderate, ≥10 severe. The LLS is used in research and expeditions to quantify altitude illness and monitor response to acclimatization or treatment. |