Treatment of moderate acute mountain sickness with pressurization in a portable hyperbaric (Gamow™) Bag

The Gamow Bag™ has recently been introduced as a treatment modality for acute mountain sick ness (AMS), but clinical experience with its use is limited. We report our use of this modality duringone season at the Himalayan Rescue Association Aid Post in Manang, Nepal (altitude 3550 m).Ten subjects with symptoms of moderate AMS were offered acetazolamide 250 mg every 12 or pressurization to 104 Torr above ambient pressure for 1 h. Four subjects were treated with acetazol amide; six underwent pressurization. Subjects undergoing pressurization experienced significant and rapid improvement in AMS symptom scores, whereas those taking acetazolamide did not. The unimproved subjects in the acetazolamide group elected to cross over to treatment with pressuriza tion, and then improved to the same degree as did subjects initially choosing pressurization. All subjects remained at altitude and subsequently crossed a 5380 m pass. This study suggests that the Gamow Bag™ may be used to rapidly alleviate the symptoms of moderate acute mountain sickness.It also suggests that a relatively short treatment period appears to offer prolonged benefit. Confir mation awaits further trials.