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Xtreme Everest is a dedicated research team of intensive care doctors, nurses and scientists based at the ISEH.

In the UK one in five of us will end up in intensive care at some point in our life. Of those 20% will die. Hypoxia, lack of oxygen reaching the body's cells and organs, is a common problem for patients who are critically ill. It is very difficult to carry out research on these patients, not least because they are so ill.

The team conduct experiments on both themselves and other volunteers at high altitude and in chambers, exploiting the oxygen-thin air, to provide critical insights into how intensive care patients might be helped in the future to improve their survival rates and recovery long-term.

In order to simulate the critical conditions of intensive care, the team have organised several medical research expeditions to Everest, the world's highest mountain. The oxygen level at base camp is about one half that found at sea level - similar to that experienced by patients in intensive care. The team have even performed tests on themselves in the "Death Zone" above 8000 metres on Everest, a height where there is barely enough oxygen to support life. Here the team measured the lowest levels of oxygen ever reported in blood in a healthy human volunteer. In all, more than 500 volunteer research participants have joined Xtreme Everest expeditions, on Everest and other mountains in the Alps and Himalayas so that they could provide invaluable data about how they adapted to low levels of oxygen similar to those seen in critically ill patients.

In 2013 the volunteer groups joining the Xtreme Everest scientists included identical twins, children, and Sherpas, as well as some of the volunteers who took part in the 2007 expedition. Data from all of the expeditions continue to be published in a variety of journals. In the last year, two research studies have commenced in critically ill patients in the UK, developed in part using knowledge gained from the Xtreme Everest healthy volunteer studies. The first of these is being conducted at the Royal Free Hospital. It is an observational study looking at tissue metabolism and blood flow in adult critically ill patients (TIMELORD). The second is a multi-centre feasibility study of a randomised controlled trial of targeted oxygen therapy in adult critically ill patients, (TOXYC).

Xtreme Everest is a not for profit organisation, led by doctors and scientists from UCL, University of Southampton and Duke University in the United States, conducting this innovative, cutting edge research. 

For further details about Xtreme Everest please contact

Xtreme Everest website


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