what is the cause of high altitude pulmonary edema
High-altitude pulmonary edema High-altitude pulmonary edema (HAPE) (HAPO spelled oedema in British English) is a life-threatening form of non-cardiogenic pulmonary edema (fluid accumulation in the lungs) that occurs in otherwise healthy mountaineers at altitudes typically above 2,500 meters (8,200 ft).[1] However, cases have also been reported at lower altitudes (between 1,500–2,500 metres or 4,900–8,200 feet in highly vulnerable subjects), though what makes some people susceptible to HAPE is currently unknown. HAPE remains the major cause of death related to high-altitude exposure, with a high mortality rate in the absence of adequate emergency treatment.
Atmospheric pressure The highest adjusted-to-sea level barometric pressure ever recorded on Earth (above 750 meters) was 1084.8 hPa (32.03 inHg) measured in Tosontsengel, Mongolia on 19 December 2001.[7] The highest adjusted-to-sea level barometric pressure ever recorded (below 750 meters) was at Agata in Evenk Autonomous Okrug, Russia (66°53’ N, 93°28’ E, elevation: 261 m, 856 ft) on 31 December 1968 of 1083.8 hPa (32.005 inHg).[8] The discrimination is due to the problematic assumptions (assuming a standard lapse rate) associated with reduction of sea level from high elevations.[7]