In altitude-related emergencies, when is immediate descent indicated as the primary management step?

• A. Severe AMS with signs of progression to HACE or any hypoxic intolerance despite oxygen therapy
• B. Mild dizziness with adequate oxygenation
• C. Persistent fatigue with no other symptoms
• D. After a short rest only

Answer: (A)

Immediate descent is the go-to move when altitude illness has reached a severe level or is turning toward high-altitude cerebral edema, especially if the patient cannot tolerate the hypoxia even with oxygen. The core idea is that lowering altitude directly reduces the environmental strain causing the symptoms, often reversing cerebral edema and improving oxygen delivery more effectively than staying put. Oxygen therapy helps and should be used, but in these worsening or oxygen-refractory situations it is not enough on its own—the priority is to move to a safer, lower altitude as quickly as possible.

In contrast, mild dizziness with adequate oxygen, fatigue without other symptoms, or resting briefly without addressing potential progression do not indicate an urgent descent.