On 23rd May 2007, a team of doctors, nurses and researchers from the University of Southampton, led by Professor Mike Grocott, reached the summit of Everest.
Their aim: to assess how the body copes with low oxygen conditions known as hypoxia.
1 in 5 people are treated in intensive care in the UK. Sadly, 25-30% of these patients die, often due to complications linked with low oxygen levels, known as hypoxia. The conditions presented in these individuals mimic those found at high altitudes; such as at the summit of Mt Everest. Here, the oxygen levels are reduced, representing only 33% of those found at sea level.
Professor Grocott and his team aimed to discover how the human body is able to adapt to these low oxygen conditions. They took arterial blood samples from themselves, identical twins and children all the way to the 29,000ft summit. The team were able to study the effect of low oxygen, establishing both genetic and environmental factors which contribute to hypoxia coping mechanisms.
Prof. Mike Grocott, Professor of Anaesthesia and Critical Care Medicine at the University of Southampton, has said this week;
“The past 10 years of work have greatly advanced our understanding of low-oxygen effects of physiological adaptations and targets for better oxygen therapy.”
Theses findings have great potential to revolutionise new hypoxia treatments; and it comes from the ability of Sherpas, indigenous to these high altitudes, to adapt to these low oxygen conditions. Blood samples taken from these individuals show an increase in mitochondrial efficiency (the energy source of the cell) compared to those living at lower altitudes. Further study into how this mechanisms evolved could lead to the identification of drug targets and hopefully life-saving treatments.
Hypoxia itself is a condition characterised by a lack of oxygen in the blood. When hypoxia occurs, it stimulates increased rate of red blood cell production in a process called haematopoiesis. Hypoxia stimulates enzymes in the cell to increase the production of erythropoietin; a factor which influences immature red blood cells to mature and divide.
In the past, many famous athletes, including Lance Armstrong, have used erythropoietin as a performance enhancing drug due to its effects on oxygen delivery to the muscle. Normally, the production of new red blood cells is enough to reverse the effects of hypoxia. However, when hypoxia is prolonged, it can result in cell and organ death. This is what contributes to the 30% of deaths in Intensive Care Units.
By researching how our bodies adapt to hypoxia, it may be possible to isolate pathways in the cell which could be used to improve the chances of survival in people with prolonged hypoxia. In a similar way to doping, it may be possible to increase the oxygen load delivered to cells and prevent cell death.
At the 10 year anniversary of this study, the discoveries are far from slowing down. Professor Grocott stated;
“We have been able to collect a vast amount of data and we hope to make it more widely available to other research teams”.
With even more data analysis in the pipeline, the potential for new findings is greater than ever. It is hoped that the continuing study will allow further insight into how hypoxia effects the brain and dementia, and that development of lifesaving treatments for a variety of illnesses will follow.
This study is part of an international collaboration between the University of Southampton, University College London, and Duke University in the USA called Caudwell Xtreme Everest.
To find out more about this collaboration, visit the non-profit organisation’s home page.