ⓘ High-altitude flatus expulsion is a gastrointestinal syndrome which involves the spontaneous passage of increased quantities of rectal gases at high altitudes. ..

                                     

ⓘ High-altitude flatus expulsion

High-altitude flatus expulsion is a gastrointestinal syndrome which involves the spontaneous passage of increased quantities of rectal gases at high altitudes. First described by Joseph Hamel in c. 1820 and occasionally described afterward, a landmark study of this phenomenon was published in 1981 by Paul Auerbach and York Miller.

The phenomenon is based on the differential in atmospheric pressure, directly correlated with the observers frequency of and level of experience in high-altitude metabolism. As the external pressure decreases, the difference in pressure between the gas within the body and the atmosphere outside is higher, and the urge to expel gas to relieve the pressure is greater. Consistent with Boyles law, controlling for dietary variance, the amount of gas produced is constant in mass, but the volume increases as the external pressure decreases.

The feeling of fullness or need to expel brought on by this differential in atmospheric pressure has been verified by studies involving military pilots subjected to pressure changes simulating flight.

                                     
  • by rapid ascent. Altitude sickness Hazards of outdoor recreation High - altitude cerebral edema HACE High - altitude flatus expulsion HAFE Roach, James
  • flatulence The root of these words is from the Latin flatus a blowing, a breaking wind Flatus is also the medical word for gas generated in the stomach