The Caudwell Xtreme Everest (CXE) expedition involved the detailed study of 222 subjects ascending to 5300 m or higher during the first half of 2007. Following baseline measurements at sea level, 198 trekker-subjects trekked to Everest Base Camp (EBC) following an identical ascent profile. An additional group of 24 investigator-subjects followed a similar ascent to EBC and remained there for the duration of the expedition, with a subgroup of 14 collecting data higher on Everest. This article focuses on published data obtained by the investigator-subjects at extreme altitude (>5500 m). Unique measurements of peak oxygen consumption, middle cerebral artery diameter and blood velocity, and microcirculatory blood flow were made on the South Col (7950 m). Unique arterial blood gas values were obtained from 4 subjects at 8400 m during descent from the summit of Everest. Arterial blood gas and microcirculatory blood flow data are discussed in detail.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1089/ham.2009.1093 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Physiological responses during ascent to high altitude and the incidence of acute mountain sickness.
Physiol Rep
April 2021
University College London Centre for Altitude Space and Extreme Environment Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport and Exercise Health, London, UK.
Article Synopsis
- - Acute mountain sickness (AMS) affects many during high-altitude ascents, and this study aimed to explore how physiological factors relate to AMS occurrence during a trek to 5300 m.
- - Out of 332 participants, 73.5% experienced AMS, with 50.3% reporting moderate-to-severe symptoms; those with no prior exposure to altitudes over 5000 m were more at risk.
- - Key predictors for developing moderate-to-severe AMS included lower peripheral oxygen saturation (SpO) levels during exercise and no previous high-altitude experience, indicating these variables could help anticipate AMS risk in future treks.
Does hypoxia play a role in the development of sarcopenia in humans? Mechanistic insights from the Caudwell Xtreme Everest Expedition.
Redox Biol
October 2017
Warwick Systems Biology Centre and Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK; Clinical & Experimental Sciences, Faculty of Medicine, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK; University Hospital Southampton NHS Foundation Trust, Southampton General Hospital, Southampton SO16 6YD, UK; Southampton NIHR Respiratory Biomedical Research Unit, UK. Electronic address:
Objectives: Sarcopenia refers to the involuntary loss of skeletal muscle and is a predictor of physical disability/mortality. Its pathogenesis is poorly understood, although roles for altered hypoxic signaling, oxidative stress, adipokines and inflammatory mediators have been suggested. Sarcopenia also occurs upon exposure to the hypoxia of high altitude.
View Article and Find Full Text PDFChanges in acute pulmonary vascular responsiveness to hypoxia during a progressive ascent to high altitude (5300 m).
Exp Physiol
June 2017
Department of Medicine, University of Washington, Seattle, WA, USA.
What is the central question of this study? Do the pulmonary vascular responses to hypoxia change during progressive exposure to high altitude and can alterations in these responses be related to changes in concentrations of circulating biomarkers that affect the pulmonary circulation? What is the main finding and its importance? In our field study with healthy volunteers, we demonstrate changes in pulmonary artery pressure suggestive of remodelling in the pulmonary circulation, but find no changes in the acute responsiveness of the pulmonary circulation to changes in oxygenation during 2 weeks of exposure to progressive hypoxia. Pulmonary artery pressure changes were associated with changes in erythropoietin, 8-isoprostane, nitrite and guanosine 3',5'-cyclic monophosphate. We sought to determine whether changes in pulmonary artery pressure responses to hypoxia suggestive of vascular remodelling occur during progressive exposure to high altitude and whether such alterations are related to changes in concentrations of circulating biomarkers with known or suspected actions on the pulmonary vasculature during ascent.
View Article and Find Full Text PDFCaudwell Xtreme Everest: A prospective study of the effects of environmental hypoxia on cognitive functioning.
PLoS One
September 2017
Health Services Research Group, City University London, College Building Room A224, London, United Kingdom.
Background: The neuropsychological consequences of exposure to environmental hypobaric hypoxia (EHH) remain unclear. We thus investigated them in a large group of healthy volunteers who trekked to Mount Everest base camp (5,300 m).
Methods: A neuropsychological (NP) test battery assessing memory, language, attention, and executive function was administered to 198 participants (age 44.
Caudwell Xtreme Everest: An Overview.
Adv Exp Med Biol
June 2017
Caudwell Xtreme Everest Research Group, London, UK.
The Caudwell Xtreme Everest (CXE) expedition in the spring of 2007 systematically studied 222 healthy volunteers as they ascended from sea level to Everest Base Camp (5300 m). A subgroup of climbing investigators ascended higher on Everest and obtained physiological measurements up to an altitude of 8400 m. The aim of the study was to explore inter-individual variation in response to environmental hypobaric hypoxia in order to understand better the pathophysiology of critically ill patients and other patients in whom hypoxaemia and cellular hypoxia are prevalent.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!