Oximetry fails to predict acute mountain sickness or summit success during a rapid ascent to 5640 meters

摘要

Objective: The purpose of this study was to determine whether arterial oxygen saturation (Spo 2) and heart rate (HR), as measured by a finger pulse oximeter on rapid arrival to 4260 m, could be predictive of acute mountain sickness (AMS) or summit success on a climb to 5640 m. Methods: Climbers (35.0 ± 10.1 years; 51 men, 5 women) were transported from 2650 m to the Piedra Grande hut at 4260 m on Pico de Orizaba within 2 hours. After a median time of 10 hours at the hut, they climbed toward the summit (5640 m) and returned, with a median trip time of 14 hours. The Lake Louise Self-Assessment Scale (LLSS) for AMS, HR, and Spo 2 were collected on arrival at the hut and repeated immediately before and after the climbers' summit attempts. Results: Average Spo 2 for all participants at 4260 m before their departure for the summit was 84.4% ± 3.7%. Thirty-seven of the 56 participants reached the summit, and 59% of all climbers met the criteria for AMS during the ascent. The Spo 2 was not significantly different between those who experienced AMS and those who did not (P =.82); neither was there a difference in Spo 2 between summiteers and nonsummiteers (P =.44). Climbers' HR just before the summit attempt was not related to AMS but was significantly lower for summiteers vs nonsummiteers (P =.04). Conclusions: The Spo 2 does not appear to be predictive of AMS or summit success during rapid ascents.