|
High altitude pulmonary edema (HAPE) is a life threatening form of non-cardiogenic pulmonary edema that occurs in otherwise healthy mountaineers at altitudes above 2500m. Some cases have however been reported also at lower altitudes (between 1500 and 2500m in highly vulnerable subjects), although what makes some people susceptible to HAPE is not currently known. HAPE remains the major cause of death related to high altitude exposure with a high mortality in absence of emergency treatment.
Aetiology The initial insult that causes HAPE is a shortage of oxygen which is caused by the lower air pressure at high altitudes.• The mechanisms by which this shortage of oxygen causes HAPE are poorly understood, but two processes are believed to be important: Although higher pulmonary arterial pressures are associated with the development of HAPE, the presence of pulmonary hypertension may not in itself be sufficient to explain the development of oedema: severe pulmonary hypertension can exist in the absence of clinical HAPE in subjects at high altitude.• Predisposing factors Individual susceptibility to HAPE is difficult to predict. The most reliable risk factor is previous susceptibility to HAPE, and there is likely to be a genetic basis to this condition, perhaps involving the gene for angiotensin converting enzyme (ACE). Research In order to help understand the factors that make some individuals susceptible to HAPE, the International HAPE Database was set up in 2005.• Footnotes See also | ||||||||
|
| |||||||||
 |
|
| |