Variables Contributing to Acute Mountain Sickness on the Summit of Mt Whitney☆

Abstract

Objective.-The interaction of 15 variables representing physical characteristics, previous altitude exposure, and ascent data was analyzed to determine their contribution to acute mountain sickness (AMS).Methods.-Questionnaires were obtained from 359 volunteers upon reaching the summit of Mt Whitney (4419 m). Heart rate and arterial oxygen saturation were measured with a pulse oximeter, and AMS was identified by Lake Louise Self-Assessment scoring. Multiple logistic regression analysis was used to identify significant protective and risk factors for AMS.Results.-Thirty-three percent of the sample met the criteria for AMS. The odds of experiencing AMS were greater for those who reported a previous altitude illness (adjusted odds ratio [OR] ϭ 2.00, P Ͻ .01) or who were taking analgesics during the ascent (adjusted OR ϭ 2.09, P Ͻ .01). Odds for AMS decreased with increasing age (adjusted OR ϭ 0.82, P Ͻ .0001), a greater number of climbs above 3000 m in the past month (adjusted OR ϭ 0.92, P Ͻ .05), and use of acetazolamide during the ascent (adjusted OR ϭ 0.33, P Ͻ .05).Conclusions.-The significant determinants of AMS on the summit of Mt Whitney were age, a history of altitude illness, number of climbs above 3000 m in the past month, and use of acetazolamide and analgesics during ascent.

Optic nerve sheath diameter, intracranial pressure and acute mountain sickness on Mount Everest: a longitudinal cohort study

“…Supporting this hypothesis are several reports of people with impaired cerebrospinal buffering capacity due to space-occupying lesions, who have developed symptoms of raised ICP when exposed either to altitude32 33 or to the hypobaric hypoxia of commercial aircraft 34. Conversely, there is a lower incidence of AMS in older people,35 who have been shown to have a greater CSF-to-brain volume 36. In our study, the three subjects with ONSD >6 mm at 5200 m all had increases in the region of 1.5 mm compared with sea level.…”

Oximetry Fails to Predict Acute Mountain Sickness or Summit Success During a Rapid Ascent to 5640 Meters

“…There appears to be no association between SpO 2 and AMS when the pulse oximetry measurement is taken soon after arriving at high altitude. 5,6 However, several researchers have suggested that low SpO 2 might be a predictor of impending AMS if the climber remains at altitude or continues a prolonged ascent. 7,8 Could finger pulse oximetry also be used to predict summit success or failure for an ascent of a high altitude peak?…”

Serious Altitude Illness in Travelers Who Visited a Pre‐Travel Clinic

“…5,16,17 However, it should also be noted that Gautret and colleagues found that older travelers are more likely to consult a physician about serious altitude illness than younger travelers, whereas Leshem and colleagues found that older climbers were more likely to be evacuated for pulmonary edema than young climbers. 6,18 Perhaps older travelers are less prone to altitude illness but when they do become ill they do not recover as quickly and thus have to be hospitalized more often.…”