On June 10, a 28-year-old female climber suffering from high altitude pulmonary edema (HAPE) was evacuated by air from 14,200-foot camp. NPS rangers assessed and treated this patient until the helicopter was able to transport her to definitive care at a local hospital.

ANALYSIS

On June 17 and June 22, two other patients were evacuated from 14,200-foot camp with HAPE or acute mountain sickness (AMS). All of these climbers had just arrived at this camp or had done a single acclimatization hike above camp. For many climbers, the low barometric pressure on Denali due to its high latitude makes the altitude feel 2,000 to 3,000 feet higher than the elevation shown on the map. Rarely does severe high-altitude illness present without prior warning lower on the mountain. Continuing to ascend in the midst of even mild altitude illness almost guarantees a worsening illness. AMS typically resolves by remaining at the current elevation for a day or two. Immediate descent is mandatory for all patients suffering from a severe altitude illness. (Source: Denali Mountaineering Rangers.)