title: Peripheral arterial desaturation is further exacerbated by exercise in adolescents with acute mountain sickness.
abstract: OBJECTIVE
  Rapid ascent to altitude can result in the development of high altitude illnesses such as acute mountain sickness (AMS). This study aimed to investigate AMS symptoms in adolescents and study basic cardiopulmonary measurements at altitude.
  
  
  METHODS
  Thirty-eight adolescents aged 16 to 19 years flew to 3500 m from 215 m and continued over a 23-day period to ascend to a maximum altitude of 5200 m. Each member of the expedition completed a Lake Louise Self-Assessment Questionnaire (LLSAQ) on a daily basis, and AMS was defined as a score of ≥ 3, with an associated headache. Physiology measurements included a step test, and both before and after exercise pulse oximetry, blood pressure, and pulse rate.
  
  
  RESULTS
  Oxygen saturation inversely correlated with altitude (P = .001). Mean pulse rate increased from 70 beats/min (± 6.5) at 215 m to 83 beats/min (± 2.2) at 3500 m (P = .01), and a rise in blood pressure with ascent was highlighted (P = .004). The majority of subjects (84%) had an LLSAQ of 3 or more on at least 1 occasion, and they tended to record higher pulse rates (P = .005) and lower oxygen saturations (P = .001). Exercise-induced drops in oxygen saturation and raised pulse rates were more prolonged in subjects with severe AMS compared with subjects not having AMS (P = .046 and P = .005, respectively).
  
  
  CONCLUSIONS
  The LLSAQ scoring system appeared to be a simple and effective technique to aid the diagnosis of adolescents who have AMS, and it may help improve the safety of large groups traveling to altitude. The AMS subjects tended to have low oxygen saturations and high pulse rates, highlighting potential areas for further research.
authors.affiliation: University Hospital Southampton National Health Service Foundation Trust, Southampton, United Kingdom. majorsarah@gmail.com
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Major
authors.forename: Ryan J K
authors.initials: RJ
authors.lastname: Hogan
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Yeates
authors.forename: Chris H E
authors.initials: CH
authors.lastname: Imray
mesh_terms: D000064:Acclimatization / Q000502:physiology; D000293:Adolescent; D000532:Altitude Sickness / Q000097:blood / Q000175:diagnosis / Q000503:physiopathology*; D001794:Blood Pressure / Q000502:physiology; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D010092:Oximetry; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen