NCT07148674

Efficacy of Positive Expiratory Pressure on Acute Mountain Sickness

Efficacy of Positive Expiratory Pressure on Acute Mountain Sickness, a Pilot Crossover Trial at 6000 Meters

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 3 (estimated)
• Sponsor: BiALP - Alpine, Disaster and Wilderness Medicine · Academic / Other
• Sex: All
• Age: 18 Years – 99 Years
• Healthy volunteers: Accepted

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.

Conditions

• Acute Mountain Sickness (AMS)

Interventions

Type	Name	Description
DEVICE	Positive Expiratory Pressure (10cmH2O) in hypobaric hypoxia	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.

Timeline

• Start date: 2025-09-05
• Primary completion: 2025-12-31
• Completion: 2025-12-31
• First posted: 2025-08-29
• Last updated: 2025-08-29