PHYSICIAN STUART HARRIS SPENDS A LOT OF TIME AT HIGH ALTITUDES—at the top of Denali in Alaska, on Mount Everest in the Himalayas and in other cold and remote locations. As a pioneer in wilderness medicine, he is looking not only at how to navigate medical crises in these places, but also at how the human body reacts—often quite poorly—to a change in elevation.

Altitude sickness may seem like a problem only for intrepid adventurers. But in an increasingly mobile culture, it is a curiously prevalent. Colorado, for instance, sees more than 1500 cases a year in their emergency rooms. The effects of elevation can be quite serious, causing edemas in the brain and lungs.

More than that, the body’s troubles at high altitude may have lessons for medicine at sea level. Low oxygen—a hallmark of elevation sickness—is also the common thread in a number of critical health conditions. “Low oxygen states are typically the way that most of my patients might ultimately die,” says Harris. “A heart attack is a low oxygen state fort the heart. A stroke is a low oxygen state for the brain.” Understanding how the body reacts to oxygen starvation at high altitudes may yield insights for these conditions, too.

The podcast also follows the story of pulmonary physician Ron Crystal, who took an ill-fated trip up Mount Everest and diagnosed his own dangerous condition along the way.

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