A self-contained life support system designed for use with a portable hyperbaric chamber.

Recently, the Gamow Bag, a portable hyperbaric chamber, has been demonstrated to relieve the symptoms of acute mountain sickness (AMS). The patient is completely enclosed in the bag which is inflated and pressurized to simulate descent in altitude. CO2 produced by the patient is vented from the airtight bag by means of a pressure relief valve, while fresh air is brought in from the outside via a high volume foot pump. In order to eliminate the vigorous pumping that is necessary to maintain a suitable atmosphere in the bag, we have designed a completely portable, self-contained life support system that supplies oxygen as it is consumed and removes the waste CO2 as it is produced. The entire rebreathing unit, which maintains a homeostatic atmosphere in the chamber for six to eight hours weighs less than six pounds. The chamber with the self-contained life support system weights less than 18 pounds. It would find its greatest use in medical mountain clinics, isolated ski areas and should become standard equipment for mountain search and rescue units.