A transportable hyperbaric chamber with soda lime for the treatment of high-altitude disorders

A transportable hyperbaric chamber called the Gamow™ bag has been reported to be effective in the treatment of high-altitude disorders in the alpine field. The problem with this device is that the operator has to endure a considerable amount of physical exercise to prevent carbon dioxide accumulation in the bag and to supplement the consumed oxygen. To solve this problem, we have applied soda lime with a respiratory circuit. In preliminary experiments, pumping twice per minute was demonstrated to be sufficient to maintain the appropriate internal conditions of the bag for 90 min. Using this system, the amount of exercise by the operator could be reduced to approximately 10% of the original value. Following the experiments, this system was practically used in the treatment of high-altitude disorders at Mustagata and at Mt. Crown (Xinjang, China). Three patients with acute mountain sickness were successfully treated using this system. Considering further possible applications, this compact system is thought to be worthwhile to carry together with the Gamow bag in alpine expeditions.