Everest Revisited

An Interview With Dr. Thomas Hornbein

(June 19, 2013)

By Curt Huber, Executive Director of ALA in Colorado

HornbeinOn May 22, 1963, Dr. Thomas Hornbein and his climbing partner, Willi Unsoeld, made the first ascent of Everest’s West Ridge. They were working their way down the other side from the summit after nightfall when they caught up with two other members of the 1963 American Mount Everest Expedition who had summited by the SE ridge route several hours before.  Unable to find the way down in the dark, the four stopped above 28,000 feet to endure  the highest unplanned bivouac in history at the time.  The four were among the first humans to summit Everest, following the original ascent by Edmund Hillary and Tenzing Norgay a decade earlier, a Swiss expedition in 1956 and a possible third ascent from the north side by the Chinese in 1963.  The bad news:  they were basically out of supplemental oxygen, they had no sleeping bags, tent, food or water.

They were clearly stuck between a rock and a cold place.  It was said later that only on rare  days does the wind not blow up there, which was a major bit of luck to their survival. When the sun rose a little after 5 a.m., they began descending toward Camp 6, the high camp above the South Col. Unsoeld and Barry Bishop ended up losing most of their toes to frostbite. 

Dr. Hornbein subsequently wrote Everest: The West Ridge, which has become something of a mountaineering classic. He is now retired from his career as an academic anesthesiologist and physiologist at the University of Washington in Seattle. He and his wife, Kathy are now living in Estes Park, the place he first discovered mountains as a thirteen year old.

Last year I had the privilege of interviewing Dr. Hornbein, at his home, which looks out at the glacier-carved peaks of Rocky Mountain National Park. As this year is the 50th anniversary of their climb (considered one of the top accomplishments in mountaineering history), I wanted to ask him about the climb, and I also wanted to hear him talk about how our lungs work at high altitude.  Here are some portions of our interview.

HUBER:  I know you developed one of the first effective oxygen masks for high altitude climbing.  How did that come about?

HORNBEIN:  In 1960 I was part of another Himalayan climb, on a 25,660 foot peak named Masherbrum in the Karakoram.  We had oxygen masks that were developed by the Swiss but found them hard to breathe through.  So after that I designed a much simpler mask. Fred Maytag, the head of the Maytag Company, put his research department to work to turn the concept into what became known as the Maytag Mask.  They worked well.

HUBER:  Can you describe the problems people have in thin air?

HORNBEIN:  Acute Mountain Sickness, or AMS, is pretty common when people come rapidly from near sea level to a place like Colorado and go quickly up to Summit County, for example, to ski or hike.  Headache and feeling lousy are the most common presenting symptoms.  There is some thought that AMS is an early form of High Altitude Cerebral Edema, or HACE, when the brain swells, although that is not universally accepted.  And, High Altitude Pulmonary Edema is a condition in which the lungs begin to fill with fluid.  Both HACE and HAPE can be fatal.

HUBER:  Is there medication that someone can take before they go to altitude?

HORNBEIN: Well, the drug of choice for AMS would be Diamox, often begun the evening before going to altitude.  Diamox also can help with the periodic breathing that occurs in some during sleep at altitude, sort of a high altitude sleeping pill.

HUBER:  Is Diamox helpful for someone who is not prone to mountain sickness, as a performance enhancer?

HORNBEIN:  No, I don’t think there’s any evidence of that.

HUBER:  What is the process of getting used to altitude?

HORNBEIN:  Time and a measured rate of ascent. The lower oxygen stimulates chemoreceptors that initiate an increase in breathing, resulting in a lowering of the partial pressure of CO2 and hence more alkaline blood pH.  The kidneys begin to unload bicarbonate to compensate.  Though this adaptation can take many days, up to 80% occurs just in the first 48 to 72 hours. There are many other physiologic changes going on, among them the stimulus of low oxygen to release the hormone, erythropoietin to stimulate more red blood cell production, a physiological and still acceptable form of blood doping that enhances endurance performance at low altitudes.
Adaptive changes are not always good for one’s health. Some South American high altitude residents can have what’s called chronic mountain sickness, resulting from too many red blood cells; their blood can be up to 84-85% red blood cells.  The increased blood viscosity and sometimes associated pulmonary hypertension can result in right heart failure.

HUBER:  This really helps me understand the importance of listening to your body at high altitudes, and spending enough time at intermediate altitudes so that your body can adapt.  Also I can see its important to observe others who may be having symptoms, and going to a lower altitude or getting medical attention if needed.  I really appreciate your time today and thanks so much for the insights.

HORNBEIN:  Good talking with you.

Editor’s note:  At the banquet of the American Alpine Club this February, Dr. Hornbein and the rest of the team- seven of the original twenty-one are still alive – were honored on the golden anniversary of the first American ascent of Everest by Jim Whittaker and Nawang Gombu on May 1 and the bold West Ridge ascent and traverse three weeks later. Hornbein continues to hike and climb in his new backyard of Rocky Mountain National Park, including on his original training ground, Longs Peak.