Altitude illness

Also known as Acute mountain sickness · High altitude cerebral oedema · High altitude pulmonary oedema · AMS HACE HAPE

Altitude illness in the emergency department — acute mountain sickness, HACE and HAPE, ataxia and the Lake Louise score, prevention with slow ascent and acetazolamide, and treatment with descent, oxygen, dexamethasone and pulmonary vasodilators.

low17 referencesUpdated 26 July 20264 min readSource-verified · Oct 2026

Checked against its sources on 24 Oct 2026

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8 MCQs

Meet the patient

A 26-year-old trekker flies to 2800 m and climbs rapidly. Two days later she has a severe headache, nausea and malaise. Her walking is unsteady and she is becoming confused.

Ataxia and confusion change the emergency. HACE is distinguished by disturbed consciousness, psychiatric changes, confusion and ataxia of gait; it often complicates acute mountain sickness or HAPE.^[16]

References17Show

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