High altitude pulmonary edema (HAPE) is a severe form of altitude illness that involves fluid buildup in a person’s lungs. HAPE can occur when an individual ascends too quickly and fails to acclimatize properly, most often at altitudes greater than 2,500m (8,200ft).
Symptoms include shortness of breath (particularly at rest), elevated heart rate, cough (often productive with frothy sputum), sensation of chest tightness, and fever. Symptoms typically begin after one to two days at high altitude and may progress rapidly. Individuals with HAPE also often experience symptoms of AMS (Acute Mountain Sickness) such as headache, nausea and vomiting, etc, but AMS does not lead to or cause HAPE.
It is also a misconception that HAPE can lead to High Altitude Cerebral Edema (HACE), another form of high altitude illness. The two are separate conditions, and although in rare cases they may occur together, one does not cause or lead to the other.
Although HAPE can happen to anyone, risk factors include age (over 65), dehydration, underlying cardiac or pulmonary conditions, and previous history of any high altitude illness. Rapid rate of ascent and vigorous exertion also increase the chance of HAPE.
HAPE is a life-threatening condition and can be fatal if not treated promptly. Rapid descent to a lower elevation is crucial to prevent further progression and complications. Treatment may also include supplemental oxygen, use of a portable hyperbaric chamber, and administration of certain medications such as Nifedipine.
If you or anyone in your group experiences any of the symptoms listed above, notify your guide or medic immediately so that appropriate action may be taken.