What is High Altitude Pulmonary Edema (HAPE)?

High Altitude Pulmonary Edema (HAPE) occurs as a result of excessive fluid in the lungs. The lack of oxygen at high altitude sometimes causes a person's blood vessels to constrict. In response, the body forces blood through unrestricted vessels, which, in turn, results in high blood pressure and blood vessel leakage. The leaked fluid builds up in the lungs, which interferes with the normal exchange of oxygen. As a result, there is further oxygen loss in the person's already-depleted bloodstream.

Because it has symptoms that are similar to pneumonia -- such as difficulty in breathing and fluid in the lungs --HAPE is sometimes misdiagnosed as pneumonia. This misdiagnosis can be a fatal error. A person who is afflicted with HAPE may suddenly fall into a coma and die within a few hours. The condition generally manifests at night, and climbers with HAPE often have been found comatose the next morning by their companions.

High-altitude pulmonary edema is a form of severe altitude illness. It is a life-threatening condition that occurs when the lungs fill with edema or fluid. Those with high-altitude pulmonary edema will commonly complain of extreme fatigue and shortness of breath (even at rest). Their breathing usually becomes fast and shallow. A cough will develop and can have frothy or pink sputum. Their breath can become gurgling or rattling and they will experience chest tightness. If their oxygen levels are low, blue or gray lips or fingernails will be noticeable.

(This answer provided for NATA by the Marist College Athletic Training Education Program.)