CEREBRAL EDEMA, PARTY SEPARATED, INEXPERIENCE
Alaska, Mount McKinley
On May 27, 1990, a three member Sophia University expedition flew onto the Southeast Fork of the Kahiltna Glacier of Mount McKinley to climb the West Buttress. The three inexperienced climbers reached the 5250 meter camp on June 11. Atuhiro Onodera (23) had a headache and no appetite upon arrival.
On June 14, the three went toward the summit, but at 5800 meters, Onodera was unable to continue due to a loss of balance, headache, and shortness of breath. He was left and his partners continued. While descending, a solo American came across Onodera and had to assist him back to 5250 meters due to his ataxia.
Onodera had no memory about the summit attempt, slept for most of the next two days, ate and drank very little, and had difficulty in walking.
By the afternoon of the 16th, the Japanese Wind Expedition examined Onodera and told the Sophia expedition they had to descend immediately. Since Onodera was having difficulty in walking, he was put on oxygen and taken from the NPS rescue cache and helped down the Rescue Gully to the NPS 4300 meter camp.
At 0200 on June 17, Onodera was examined by Ranger Scott Gill. Onodera was unable to perform the heel to toe test without falling down. He was put on oxygen for 45 minutes and seemed to improve immensely. After an evening at the NPS camp, he was able to descend under his own power and flown out from basecamp. (Source: Scott Gill, Mountaineering Ranger, Denali National Park)