Survey of acute mountain sickness on Mauna Kea.

Although thousands of people ascend 4205 m to visit the summit of Mauna Kea each year, there has been no information on the rate of altitude illness triggered by such visits. Two surveys were used: one for tourists driving up to the summit and the other for summit astronomy workers staying at lodging facilities at intermediate altitude. The surveys included the standardized Lake Louise Self-report Acute Mountain Sickness (AMS) Questionnaire that, when scored, gave the Lake Louise Symptoms Score (LLSS). Thirty percent of surveyed day visitors and 69% of surveyed professional astronomy staff had AMS, defined as a LLSS score of 3 or greater, with headache. Nine participants reported "disorientation/confusion" or greater consciousness changes. A majority of astronomy professionals reported fatigue, disturbed sleep, reduced activity, and mental status changes. Few took any AMS medications. The incidence of AMS in visitors to Mauna Kea's summit warrants increased education and increased availability of supplemental oxygen at the summit. The absence of reported serious altitude illness in the community is probably due to the rapid descent available on Mauna Kea, with prompt reversibility of adverse effects.