High urgency
-Very severe
As in stroke, it corresponds to the lack of blood supply and oxygenation of a group of neurons in the brain.
It is due to the obstruction of cerebral circulation by a blood clot. The formation of the clot at an altitude of 3000m is favoured by an increase in blood viscosity. The blood thickens due to an increase in red blood cells, dehydration and lack of oxygen in the blood.
Dizziness, headache, impaired vision, impaired speech, and impaired strength or sensation appear suddenly.
The diagnosis is clinical and it is characteristic that the symptoms improve when descending in altitude and breathing oxygen.
It is considered a life-threatening emergency and requires immediate descent and oxygen therapy.
- Scott A Gallagher, MD. Peter Hackett, MD. Jonathan M Rosen, MD. High altitude illness: Physiology, risk factors, and general prevention. UpToDate, Apr 15, 2015.
- Scott A Gallagher, MD. Peter Hackett, MD. Acute mountain sickness and high altitude cerebral edema. UpToDate. Mar 03, 2016.
- West JB, American College of Physicians, American Physiological Society. The physiologic basis of high-altitude diseases. Ann Intern Med 2004; 141:789.
- Schoene RB. Illnesses at high altitude. Chest 2008; 134:402.
Dr. Oscar Garcia-Esquirol
Copyright© TeckelMedical 2026
