Help docs! i'm trying to find out what causes high altitude cerebral edema?

Hypoxia: When a person goes to high altitude, they are naturally exposed to hypoxia as oxygen content decreases with elevation. Most who climb can to aclimatize to this change. However, in certain people they are not able to compensate. The proton pumps that maintain the blood brain barrier cease to function and there is extra fluid (edema) in the brain that leads to brain swelling. This can lead to death.