Researching patient hypoxia through high-altitude exposure

Xtreme Everest’s expedition to Mount Everest in 2007 successfully turned the world’s highest peak into the most extreme laboratory on Earth. The team conducted a number of experiments at high altitude, which mimics hypoxia experienced by patients in intensive care units (ITU). Xtreme Everest will return to the Himalayas later this year to conduct additional tests in the hope of gaining further understanding. As before, the team will be using blood gas analysers from Siemens Healthcare Diagnostics to conduct its research. Up to 40% of patients treated in ITU die,1 so it is hoped that conducting the research will provide insight and understanding into why some intensive care patients survive under such circumstances, and others do not.

The first round of research conducted over five years ago provided the team with a number of insights into how capillaries running throughout the body’s tissues and organs are affected and how they change as a result of hypoxia. Xtreme Everest also identified interesting changes in how low oxygen affects people’s nitric oxide metabolism, which the team of medical professionals believe in turn controls the micro-circulation and mitochondria. During this second trip to Everest, the team will investigate these two elements in greater detail and examine how both are affected by adjustments to nitric oxide levels.

Unique finding
Over 200 volunteer subjects joined the team at the Everest Base Camp in 2007 to help provide crucial data into how well they adapted to changes in oxygen levels. Xtreme Everest expedition leader for this year’s visit, Dr Daniel Martin, was a member of the original team that continued further up towards the summit. A critical care specialist at the Royal Free Hospital in London, Dr Martin was recorded to have the lowest blood oxygen level ever in a human being at 2.55 kilopascals (kPa), 80% below normal levels (12–14 kPa). The blood sample was taken just 400 m beneath the summit. Despite experiencing such a low level of hypoxia, less than half the threshold usually seen in urgent intensive care admissions, he was able to walk and talk normally.