High Altitude Pulmonary Edema, or HAPE, is the most common and most fatal form of high altitude sickness. HAPE results from fluid building up in the lungs over time while at high altitude. Essentially, victims of HAPE take in less and less oxygen due to the low air pressure at high altitudes as fluid continues to fill up their lungs, resulting in eventual asphyxiation if medical treatment is not received. Doctors do not know what triggers it and why it effects some people rather than others.
HAPE is tricky because there is no telling who will suffer from it. Although most patients report developing HAPE at altitudes higher than 8,000 feet, there are many cases reported at significantly lower altitudes. It typically strikes otherwise healthy skiers, mountaineers, and other outdoorsmen. Because it usually develops over 2-3 days, many outdoorspeople unknowingly allow the condition to get worse and continue to ascend higher up the mountain. This contributes to the high mortality rate of HAPE; people continue to trek further away from medical treatment, so when they really cannot breathe near the top of the mountain they have a much longer trip down than when they first began showing symptoms.
That is why it is important for anyone at high altitude showing any of the symptoms of HAPE to seek medical attention as quickly as possible. According to altitude.org, the most telling symptoms of HAPE are being constantly out of breath, fatigue, and having a cough with a frothy, pink or white phlegm. Other symptoms include wheezing, irregular heartbeat, and blue lips/face.
The best treatment for HAPE is descending from altitude as quickly as possible. Interestingly enough, some doctors have found treating patients with Sladenafil (better known as Viagra) allows for quicker recovery as it opens up blood vessels in the lungs (and other places…). However, the bottom line is that immediate descent is crucial for surviving HAPE. Anyone reaching altitudes higher than 8000 feet should definitely become familiar with the signs and symptoms of HAPE and come up with a plan for rapid descent of the mountain so as to stay alive on their next outdoor adventure.