title: The physiological effects and quality of chest compressions during CPR at sea level and high altitude.
abstract: BACKGROUND
  Rescuers that undergo acute ascent without acclimatization can experience acute mountain sickness. Although performing cardiopulmonary resuscitation (CPR) for a short period requires intensive effort at sea level, performing CPR at high altitude is even more exhausting and can endanger the rescuer. Therefore, we conducted a pilot study to compare the quality of resuscitation in health professionals at high altitude (3100 m) and that at sea level.
  
  
  METHODS
  Thirty-eight participants were asked to performed continuous chest compression CPR (CCC-CPR) for 5 minutes at sea level and at high altitude. Cardiopulmonary resuscitation recording technology was used to objectively quantify the quality of the chest compressions (CCs), including the depth and rate thereof.
  
  
  RESULTS
  At high altitude, rescuers showed a statistically significant decrease in blood oxygen saturation and an increase in systolic blood pressure, diastolic blood pressure, heart rate, and fatigue, as measured with the Borg score, after CCC-CPR compared with resting levels. The analysis of the time-dependent deterioration in the quality of CCC-CPR showed that the depth of CCs declined from the mean depth of the first 30 seconds after CCC-CPR to that at more than 120 seconds after CCC-CPR at both sea level and high altitude. The average number of effective CCs declined after CCC-CPR was performed for 1 minute at sea level and high altitude.
  
  
  CONCLUSIONS
  The quality of CC rapidly declined at high altitude. At high altitude, the average number of effective CC decreases; and this decrease became significant after continuous CCs had been performed for 1 minute.
authors.affiliation: Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Jen-Chun
authors.initials: JC
authors.lastname: Wang
authors.affiliation: Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Shih-Hung
authors.initials: SH
authors.lastname: Tsai
authors.affiliation: Department of Emergency Medicine, Buddhist Tzu Chi General Hospital, Taipei Branch, Taipei, Taiwan.
authors.forename: Yu-Long
authors.initials: YL
authors.lastname: Chen
authors.affiliation: Department of Emergency and Critical Care Medicine, Taipei Medical University-Wan Fang Hospital, Taipei, Taiwan.
authors.forename: Chin-Wang
authors.initials: CW
authors.lastname: Hsu
authors.affiliation: Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Kuan-Cheng
authors.initials: KC
authors.lastname: Lai
authors.affiliation: Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Wen-I
authors.initials: WI
authors.lastname: Liao
authors.affiliation: Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Ling-Yuan
authors.initials: LY
authors.lastname: Li
authors.affiliation: Department of Emergency & Critical Care Medicine, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Wei-Fong
authors.initials: WF
authors.lastname: Kao
authors.affiliation: Department of Emergency Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Ju-Sing
authors.initials: JS
authors.lastname: Fan
authors.affiliation: Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan. Electronic address: chen.yinghsin@gmail.com.
authors.forename: Ying-Hsin
authors.initials: YH
authors.lastname: Chen
mesh_terms: D000328:Adult; D000531:Altitude; D000532:Altitude Sickness / Q000503:physiopathology; D001794:Blood Pressure / Q000502:physiology*; D016887:Cardiopulmonary Resuscitation / Q000592:standards*; D005221:Fatigue / Q000503:physiopathology*; D005260:Female; D006282:Health Personnel; D006336:Heart Massage / Q000592:standards*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D010092:Oximetry; D010865:Pilot Projects; D013997:Time Factors; D055815:Young Adult