The human body functions best at sea level. Down here, oxygen levels are sufficient for our brains and lungs. At much higher altitudes, our body cannot function properly.
But if climbers want to scale Mount Everest, the world’s highest peak at 29,029 feet (8,848 meters or 5.5 miles) above sea level, they must brave what’s known as the “zone of death”.
This is the area over 8,000 meters above sea level, where there is so little oxygen that the body begins to die, minute by minute and cell by cell.
In the death zone, climbers’ brains and lungs are deprived of oxygen, their risk of heart attack and stroke is increased, and their judgment is rapidly impaired.
“Your body basically breaks down and dies,” Shaunna Burke, a mountain climber who summitted Everest in 2005, told Business Insider. “It becomes a race against time.”
In 2019, at least 11 people died on Everest, almost all of whom spent time in the death zone. It became one of the deadliest Everest seasons in recent memory.
Some expedition companies blamed the deaths on overcrowding, noting that the summit was so choked with climbers during a rare spell of good weather that people were stuck in the death zone for too long.
On May 22, 2019, 250 climbers attempted to reach the summit, the Kathmandu Post reported, and many climbers had to queue up and down.
This unplanned overtime in the death zone could have put the 11 people who perished at higher risk, although it is difficult to determine the specific causes of each death.
Climber says climbing Everest is like ‘running on a treadmill and breathing through a straw’
At sea level, the air contains about 21% oxygen. But at altitudes above 12,000 feet, oxygen levels are 40% lower.
Jeremy Windsor, a doctor who climbed Everest in 2007 as part of the Caudwell Xtreme Everest expedition, told Everest blogger Mark Horrell that blood samples taken from four climbers in the death zone have revealed that climbers survived on only a quarter of the oxygen available to them. required at sea level.
“These were comparable to numbers found in patients near death,” Windsor said.
Five miles above sea level, the air contains so little oxygen that even with extra air tanks, it can feel like “running on a treadmill and breathing through a straw,” according to mountaineer and filmmaker David Breashears.
Climbers must acclimatize to the lack of oxygen
A lack of oxygen leads to a myriad of health risks. When the amount of oxygen in your blood drops below a certain level, your heart rate goes up to 140 beats per minute, increasing your risk of a heart attack.
Climbers should give their bodies time to acclimate to the lung-crushing conditions in the Himalayas before attempting to climb Everest.
Expeditions typically make at least three trips up the mountain from Everest Base Camp (which is higher than almost any mountain in Europe at 17,600 feet), ascending a few thousand feet higher on each successive trip before pushing to the top.
During those weeks at high altitude, the body begins to make more hemoglobin (the protein in red blood cells that helps carry oxygen from the lungs to the rest of the body) to compensate.
But too much hemoglobin can thicken your blood, making it harder for the heart to pump blood throughout the body. This can lead to a stroke or the buildup of fluid in your lungs.
On Everest, a condition called high altitude pulmonary edema (HAPE) is common – a quick check with a stethoscope can reveal a clicking sound as fluid that has leaked into the lungs vibrates.
Other symptoms include fatigue, an impending feeling of choking at night, weakness, and a persistent cough that brings up a white, watery, or foamy liquid. Sometimes the cough is so intense that it can crack or separate the ribs.
Climbers with HAPE are always short of breath, even at rest.
In the death zone, your brain may begin to swell, which can lead to nausea and a form of psychosis
Acclimatization to death zone altitudes is simply not possible, high altitude expert and physician Peter Hackett told PBS.
One of the biggest risk factors at 26,000 feet is hypoxia, a lack of adequate oxygen flow to organs like your brain. If the brain doesn’t get enough oxygen, it can begin to swell, causing a condition called high altitude cerebral edema (OCHA). Essentially, it’s HAPE for the brain.
This swelling can trigger nausea, vomiting, and difficulty thinking and reasoning.
An oxygen-starved brain can cause climbers to forget where they are and go into a delirium that some experts consider a form of high-altitude psychosis.
Hypoxic climbers’ judgment is impaired, and they’ve been known to do weird things like start stripping or talking to imaginary friends.
Other possible dangers include insomnia, snow blindness and vomiting
Burke said that while climbing, she suffered from a constant, relentless cough.
“Every second or third breath your body takes in air and you wake up,” she said.
The air was so thin that she was unable to sleep properly.
“Humans are going to start deteriorating,” Hackett added. “Sleep becomes an issue. Muscle wasting occurs. Weight loss occurs.”
Nausea and vomiting due to altitude-related illnesses, including OPHA and OCHA, also cause decreased appetite. The glare from endless snow and ice can cause snow blindness – temporary vision loss or bursting of blood vessels in your eyes.
Temperatures in the death zone never exceed zero degrees Fahrenheit. “Any exposed skin freezes instantly,” Burke said.
Loss of blood flow to climbers’ fingers and toes can cause frostbite and, in severe cases – if the skin and underlying tissue die – gangrene. Gangrenous tissue often has to be amputated.
All this physical weakness and impaired vision can lead to accidental falls. Fatigue is everywhere, according to Burke.
“It takes everything to put one foot in front of the other,” she said.
Poor decision-making can also lead to climbers forgetting to attach themselves to a lifeline, straying from the route, or not properly preparing rescue equipment like oxygen tanks.
Mountaineers climb through the Death Zone in a day, but they can end up queuing for hours
Climbing into the death zone is “living hell,” as Everest climber and 1998 NOVA expedition member David Carter told PBS.
Typically, climbers attempting to reach the summit try to ascend and descend in a single day, spending as little time as possible in the death zone before returning to safer altitudes. But this frantic push towards the finish line comes after weeks of escalation.
Lhakpa Sherpa, who has summited Everest nine times (more than any other woman on Earth) previously told Business Insider that the day a group tries to climb Everest is by far the toughest time in the world. trekking.
To make it to the top, everything has to be fine. Around 10 p.m., climbers leave Camp Four at 26,000 feet. The first part of their ascent is in the dark, lit by starlight and headlamps.
About seven hours later, climbers usually reach the summit. After a brief rest filled with celebration and photography, the expeditions turn back, making the 12-hour journey to safety and arriving (ideally) before dark.
This article was originally published by Business Insider.
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