A cooler way to deal with trauma

It's still controversial, but evidence is mounting that keeping trauma patients cold can save lives, says Michael Mosley
doctors in surgery
Doctors can reduce body temperatures to 16C during surgery. Photograph: Christopher Furlong/Getty Images

A cooler way to deal with trauma


It was 3am on a bitterly cold January morning and we were staying in a cottage in Dorset when there was a loud banging on the front door. We stumbled downstairs and there was one of the neighbours holding our 11-year-old son, Alex, with his head covered in blood.

The neighbour had been walking around his garden when he heard a groaning sound and found Alex unconscious on the ground beneath our open window. Presumably he had been sleep walking, tipped out of the window and fallen 12 feet on to his head.

He was deeply unconscious and clearly had a fractured skull. My wife is a doctor and the standard advice would be to take him inside and keep him warm while waiting for an ambulance. But I had recently made a film about the neuroprotective properties of cold, so rather than wrap him up we stripped him down and packed his skull with ice.

It was an incredibly traumatic journey to the hospital and the waiting neurosurgeons. All the way there I was wondering if he would live and if we had done the right thing.

What we were doing was controversial. The standard advice in a trauma situation is keep the patient warm because cold slows down the clotting process. Continuing to bleed is bad if you have an external injury, particularly bad if you have something like a skull fracture because of the potential build up of pressure on the brain.

I knew, however, about research done with soldiers who had survived the Falklands War, which suggested that cold might have benefits that outweigh the downside. I had interviewed a soldier who'd had his leg blown off during a mortar attack and despite being left out on a chilly hillside overnight, had not only survived but made a good recovery. Doctors who've studied cases like his believe that cold slows down or even switches off some of the toxic cascade of events that follow extreme trauma.

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 was there very recently, in the department of critical care, when a patient with a gunshot wound was wheeled in. His heart had stopped.

The team tried to get his heart going and when that didn't work they pumped his veins full of ice-cold saline solution, enough to induce a state of extreme hypothermia, similar to what I had seen in Sophie. He was then rushed off for emergency surgery.

At least that is what they would have done if this had been a genuine emergency and not just a practice for the real thing.

Dr Sam Tisherman, who will run the trial, explained why he thinks that using cold is so effective.

"We think it's beneficial not just because it reduces your tissue's demand for oxygen but also because it reduces the deleterious chemical cascades that occur after trauma. Lots of bad things happen when you don't have blood flow to your vital organs for a period of time."

He accepts that there are risks but also points out that at the moment only one in 10 people who have a cardiac arrest because of trauma survive.

"We know that what we're doing now doesn't work. Something like this is exciting because we might be able to save substantially more".

And as for my son? Things turned out fine. He had a badly fractured skull and for a while looked terrible, but he has since made an excellent recovery. His life was certainly saved by our neighbour, but did the cold also help? I like to think so.

Michael Mosley presents Frontline Medicine on BBC Two at 9pm on Sunday 20 November 2011 on how war has driven medical advances