From a Washington Post obit by Harrison Smith headlined “Tom Hornbein, who blazed a new trail up Everest, dies at 92”:

Thomas F. Hornbein, a mountaineer and anesthesiologist who climbed into history, step by icy step, when he and his friend Willi Unsoeld scaled Mount Everest in 1963 — pioneering a route up the treacherous West Ridge before surviving a night at 28,000 feet without sleeping bags or a tent — died at his home in Estes Park, Col.

Dr. Hornbein, who continued to do roped climbs into his mid-80s, was 92 and had leukemia.