Expeditions to Everest have claimed 212 livesDecember 10th, 2008 - 4:57 pm ICT by IANS
Washington, Dec 10 (IANS) Expeditions to Mount Everest, the world loftiest peak, have claimed 212 lives between 1921 and 2006, including 192 above the base camp.Most of these deaths occurred above 8,000 metres during descent from the 8,850-metre-high summit.
A team led by Massachusetts General Hospital (MGH) investigators, conducting the first detailed analysis of such deaths, identified factors like high altitude cerebral edema that appear linked with fatalities.
“We know that climbing Everest is dangerous, but exactly how and why people have died had not been studied,” said Paul Firth of the MGH department of anesthesia who led the study.
“It had been assumed that avalanches and falling ice - particularly in the Khumbu Icefall on the Nepal route - were the leading causes of death and that high-altitude pulmonary edema would be a common problem at such extreme altitude. But our results do not support either assumption.”
“The majority of those who have died on Everest were in the prime of their lives, with families and friends left bereft,” stressed Firth, according to an MGH release
Factors most associated with the risk of death were excessive fatigue, a tendency to fall behind other climbers and arriving at the summit later in the day.
Many of those who died developed symptoms such as confusion, a loss of physical coordination and unconsciousness, which suggest high-altitude cerebral edema, a swelling of the brain that results from leakage of cerebral blood vessels.
The research team, comprising investigators from three British hospitals and University of Toronto - reviewed available records including the Himalayan Database, a compilation from all expeditions to 300 major peaks in the world’s highest range.
More detailed analysis was conducted on deaths occurring above 8,000 metres during the past 25 years. Deaths were categorised as traumatic, from falls or external hazards such as avalanches; nontraumatic, from high-altitude illness, hypothermia or other medical causes; or as disappearances.
Expedition climbers were classified as either ‘climbers’, individuals from outside the Himalayan region, or ’sherpas’ - high-altitude porters, most of them ethnic Sherpas or Tibetans, hired to transport equipment and otherwise assist the climbers.
The overall mortality rate for Everest mountaineers during the entire 86-year period was 1.3 percent; the rate among climbers was 1.6 percent and the rate among sherpas was 1.1 percent.
The report is scheduled for publication in December issue of the British Medical Journal.
Tags: british hospitals, cerebral blood vessels, external hazards, extreme altitude, high altitude cerebral edema, high altitude pulmonary edema, khumbu icefall, massachusetts general hospital, physical coordination, swelling of the brain