Daring doctors are preparing to scale Mount Everest in a groundbreaking research project which they hope will yield a breakthrough in the care of intensive care patients.

University College London Hospital is leading an expedition of scientists, medics and Nepalese sherpas to scale the world’s highest peak to test whether people’s reactions to low oxygen levels is determined by genetics or our environment.

Using themselves as lab rats, doctors will endure freezing temperatures of -25 degrees and study how they and their fellow climbers react to their onerous surroundings, charting the differences.

It marks the second stage of the mammoth research project that five years ago saw the same group of doctors climb the Himalayan mountain to begin the tests.

The results showed that climbers at the top of Everest had lower levels of oxygen in their blood than people in intensive care, raising fresh questions over why two fifths of people in intensive care in the UK die.

Doctors believe that hypoxia, a lack of oxygen reaching the body’s vital organs, is one of the reasons so many patients die, but the research suggests it is not a shortage of oxygen alone that accounts for the high death rate.

Kay Mitchell, manager of the centre for altitude and extreme space and environment medicine (CASE) at UCL, said: “One of the things we are particularly interested in is epigenetics, which looks at the interaction between genes and environment.

“It is not just your DNA that affects how you respond to things, but the environment that you have been in or are in. Identical twins have the same DNA. We want to see if they respond in the same way or not.

Ambitious

“We don’t think it’s as simple as what your DNA is. We want to find out if there’s an environmental component to how you respond to oxygen levels.”

Ms Mitchell, who is among the team who will embark on the ambitious expedition, said findings made at the top of a mountain could transform care in hospital wards.

She said: “Everything we’re doing is trying to improve outcome of patients who are critically ill.

“There are a multitude of factors that affect how you respond to poor oxygen levels and we’re trying to get to the bottom of that.”