My faith in the power of cold was also reinforced by watching cardiac surgeon, Stephen Westaby, operate on 34-year-old, Sophie. She had been born with multiple life-threatening heart defects, the most important being an aneurism, a weakened section of artery. Her main artery, the aorta, had ballooned and would eventually burst if not replaced with a section of artificial artery. It would be slow fiddly work, involving reconnecting the blood vessels that go to the brain. All of which would take time.

After anaesthetising her, the team connected Sophie to a heart-lung machine. Then they injected with her with potassium chloride to make her heart stop. Meanwhile the heart lung machine was not only oxygenating her blood, but also cooling it.

An hour into the operation and instead of a normal body temperature of 37C, Sophie's core temperature was down to just 16C. She had no pulse and there were no signs of brain activity on the EEG. She was cold, pulseless, apparently dead.

Steve patched up her aorta, sorted out another problem with her valves and after an hour and a half they warmed her up again. She went on to make a good recovery.

The case for cold seemed to be building. It reduces inflammation and at the same time slows the metabolic demands of the body. So why not dramatically cool people down when they have had some extreme form of trauma, whether it is a head injury, a heart attack or massive loss of blood?

To find the pros and cons you have to do a proper clinical trial. Such a trial, funded by the military, is due to start any day now at the University of Pittsburgh.

[I've have heard of this before in respect ot people who go into cardiac arrest. It would seem to improve their chances of survival considerably.]