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Mortality on Mount Everest, 1921-2006: descriptive study.

Paul G Firth¹, Hui Zheng, Jeremy S Windsor

¹Department of Anesthesia and Critical Care, Massachusetts General Hospital, Boston, MA 02114, USA. pfirth@partners.org

BMJ (Clinical Research Ed.)

|December 17, 2008

Summary

Mount Everest climbing deaths are often due to trauma or high altitude illness, especially during descent. Fatigue and late summit times are early warning signs for climbers.

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Area of Science:

Environmental Science
Human Physiology
Mountaineering Safety

Background:

Mount Everest expeditions have a long history, attracting both professional climbers and support staff (Sherpas).
Understanding mortality patterns is crucial for improving safety on high-altitude expeditions.

Purpose of the Study:

To analyze mortality trends among Mount Everest climbers over an 86-year period (1921-2006).
To identify causes and circumstances of death for both climbers and Sherpas.

Main Methods:

A descriptive study analyzing data from 14,138 mountaineers (8,030 climbers, 6,108 Sherpas) on Mount Everest.
Examined circumstances of deaths, including cause (trauma, non-traumatic, disappearance) and timing during the expedition.

Main Results:

Overall mortality rate above base camp was 1.3%.
Deaths were attributed to trauma (47%), non-traumatic causes (21%), and disappearances (11%).
The death rate during descent was significantly higher for climbers than Sherpas (2.7% vs. 0.4%).
Late summit times and symptoms like fatigue and cognitive changes were associated with higher mortality.

Conclusions:

High-altitude cerebral edema symptoms are common during descent from Mount Everest.
Profound fatigue and delayed summit ascent times are critical indicators of increased mortality risk.