High-altitude pulmonary oedema - HAPO

Critical urgency
-Very severe

It is the accumulation of fluid in the lungs that occurs at altitudes above 2500m as a result of the pressure difference above sea level.

The amount of oxygen in the air decreases and the same happens in the organs and in the blood, causing arterial hypertension in the lungs and water retention.

This situation causes fatigue and slower recovery from exertion, progressive shortness of breath (with altitude), coughing and frothy phlegm.

It is diagnosed on the basis of the symptoms described above, which occur when climbing to this altitude.

Treatment is urgent and involves the descent of the person and oxygen therapy. Acetazolamide, dexamethasone and beta-2 agonists can be used to speed up recovery.

Without proper treatment, 40% of people die.

Bibliographic references
  1. Scott A Gallagher, MD. Peter Hackett, MD. Jonathan M Rosen, MD. High altitude illness: Physiology, risk factors, and general prevention. UpToDate. Apr 15, 2015.
  2. Schoene RB. Illnesses at high altitude. Chest 2008; 134:402.
  3. Scott A Gallagher, MD. Peter Hackett, MD. High altitude pulmonary edema. UpToDate. Sep 26, 2016.
  4. Stream JO, Grissom CK. Update on high-altitude pulmonary edema: pathogenesis, prevention, and treatment. Wilderness Environ Med 2008; 19:293.
  5. Scherrer U, Allemann Y, Rexhaj E, et al. Mechanisms and drug therapy of pulmonary hypertension at high altitude. High Alt Med Biol 2013; 14:126.
Author
Dr. Sara Vitoria
Copyright
© TeckelMedical 2026

Symptoms

    Short of breath


    Bubbling pot noise when breathing


    Cough up pink mucus


    Cough


    Shortness of breath at rest

Pre-hospital care recommendations

Descend below clearance height (< 2.500 metres).