Pulse oximetry in the diagnosis of acute mountain sickness.

Acute mountain sickness (AMS) is a common condition in individuals who travel to altitudes over 2000 m. While AMS is an important public health problem, no measurements can reliably support or predict the diagnosis with any degree of confidence. We therefore set out to study whether pulse oximetry data are associated with AMS. We studied 169 subjects who had recently arrived by foot at 3080 m. Subjects completed a demographic survey, which collected data on ascent profiles and AMS symptoms. Resting arterial oxygen saturation and pulse rate were then measured using finger pulse oximetry. Forty-six subjects (27%) had AMS, using the Lake Louise score. Only pulse rate was significantly associated with the presence of AMS (OR: 1.4; 95% CI, 1.1 to 1.9; p < 0.05, backwards stepwise logistical regression). A trend showed worse AMS diagnoses were associated with higher mean pulse rates (p < 0.05, ANOVA linear weighted analysis). While some previous studies have shown an association between decreased oxygen saturation and acute mountain sickness at altitude, our results did not demonstrate such an association. The utility of pulse oximetry remains limited in the diagnosis of AMS. We recommend further study to determine the possible utility of pulse rate in the diagnosis and prediction of AMS.