I trained in anaesthesia and intensive care medicine and undertake clinical work on the intensive care unit at Derriford hospital in Plymouth. I was previously based at University College London where I was awarded a PhD in applied physiology. 

 

My main research interest is how humans respond to different levels of oxygen; both too much (hyperoxia) and too little (hypoxia) of it. I have been involved in and led several research expeditions to high altitude and in 2007 summited Mount Everest with the Xtreme Everest team. On the summit a blood gas taken showed I had one of the lowest oxygenation readings ever recorded in a human. 

 

I am currently the chief investigator for the NIHR funded UK-ROX trial, evaluating whether giving a little less oxygen than usual to critically ill patients will improve their survival. It is the largest trial ever conducted in UK intensive care units and we have now successfully recruited 16,500 patients from 100 NHS sites. In a sub-study of the UK-ROX trial that I lead (the EXAKT study) we have investigated the accuracy of pulse oximeters (which estimate blood oxygen levels in patients) to determine whether skin tone affects their readings. 

 

I am also very interested in exercise and how it can be used to improve clinical outcomes. We have used a tailored exercise intervention to train patients waiting for liver transplantation and I am the co-chief investigator of the NIHR-funded EXALT trial in which we will further evaluate the effect of exercise around the time of liver transplantation. I am also invoked with a study to explore the benefits of exercise programmes in patients awaiting bariatric surgery.

 

I have been the Editor in Chief of the Journal of the Intensive Care Society for the last six years and sit on the Council of the Intensive Care Society. I am the editor of the soon to be published 9th edition of Oh's Intensive Care Manual, a best selling comprhensive textbook of intensive care medicine. I also sit on the Medicines and Healthcare products Regulatory Agency (MHRA) interim devices working group.

 

I have published over 200 peer reviewed articles that have over 16,000 citations. I have delivered over 160 lectures to audiences around the world including 15 plenary / keynote speeches.  I made a notable contribution to the Equity in Medical Devices: Independent Review for the Department of Health and Social Care in 2024

 

I was awarded Officer of the Order of the British Empire (OBE) in the 2016 New Years Honours list, for services to the prevention of infectious diseases. This was the result of my contribution to the care of UK healthcare workers who succumbed to Ebola virus disease.

 

I spent a large part of my earlier life climbing and have summited mountains such as Denali (Alaska), Cho Oyu (Nepal) and Everest (Nepal). I have also sailed for most of my life, both in dinghies and yachts. These days though I am mainly trying to encourage two toddlers hike on Dartmoor.