Mountain climbers going beyond 24000 ftmay succumb to Hape or Hace.What are they and why do they occur?

Question

Mountain climbers going beyond 24000 ftmay succumb to Hape or Hace.What are they and why do they occur?

Answer 1

http://www.altitude.org/hace.htm

Even though there is O2 up there, The atmospheric pressure is less and it is harder for the lungs to take in.  Pressure always goes from high to low.  

At sea level the atmospheric pressure 760 and the lungs is less and the intraplural pressure is 756 so the thoracic cavity is always able to take in the pressure.  If the pressure outside is less it is a lot harder for the body to take in the air from outside because the pressure is greater inside the lungs.

Answer 2

High Altitude Pulmonary (or Cardio) Edema.  Lack of oxygen in the blood causes a build up of fluid, which can flood the lungs or chest cavitry, causing a medical emergency.  This happens, particularly if the climber rises too high too soon, and doesn't acclimatise his body to the lower oxygen content.  If the climber isn't evacuated to a lower altitude quickly, or given oxygen, he is in grave danger.  Many deaths occur because of HAPE; it is one of the most dangerous hazards of high altitude climbing.