Where Oxygen Fades: Assessing Efficacy of a Portable Hyperbaric Mask for High-Altitude Hypoxia, a Pilot Crossover Trial

Introduction: The incidence and severity of acute mountain sickness (AMS) escalate with altitude. If left untreated, AMS can progress to high-altitude pulmonary edema (HAPE) or high-altitude cerebral edema (HACE), both potentially fatal. The most effective treatment involves rapid descent to lower altitudes with increased oxygen availability. Portable hyperbaric bags have traditionally been used to simulate a lower altitude environment; however, their bulk and weight restrict usability. This study aims to evaluate the efficacy of a novel portable hyperbaric mask, which is lighter, compact, and allows simultaneous access to the patient’s vascular system and mobility during use. The primary endpoint is the change in oxygen saturation before, during, and after mask use at high altitude. Secondary endpoints include subjective respiratory distress and AMS symptoms. Methods: This pilot prospective self-controlled, intervention-focused crossover trial, conducted in two phases, will evaluate a novel 3D-printed portable hyperbaric mask in healthy volunteers. Phase 1 will take place at Rifugio Torino in the Italian Alps (3375m). Baseline measures for oxygen saturation, subjective respiratory distress, and AMS symptoms, assessed by the Lake Louise Score, will be recorded for each participant before mask application. These parameters will be reassessed at intervals during mask application and after removal. Phase 2 will replicate the procedure at higher altitudes, first at Aconcagua Base Camp (4200m) and later at the summit (6960m). Data collection is scheduled between December 2024 and February 2025. Results: We anticipate observing notable variations in oxygen saturation, subjective respiratory distress, and AMS symptoms, correlating with mask use at various altitudes. Conclusion: This study aims to assess the portable hyperbaric mask’s effectiveness in alleviating AMS symptoms and potentially preventing HAPE and HACE.