Between Life and Death – The Power of Therapeutic Hypothermia

When Anna Bågenholm fell while skiing and became trapped in icy water, her body temperature plummeted and her heart stopped, but doctors were able to bring her back to life. Her extraordinary story has led to therapeutic hypothermia being used around the world

Deep in the heart of northern Norway lies the Kjølen mountain range, a series of jagged peaks that line the Swedish border. This bleak Arctic wilderness, more than 100 miles from any major hospital, may seem an unlikely setting for an event that changed medical history but, 14 years ago, the miraculous survival story of Anna Bågenholm for ever redefined our understanding of the boundary between life and death.

Bågenholm, a trainee doctor, was skiing off-piste with two of her colleagues when she lost control during a steep descent, falling on to a layer of ice covering a mountain stream. A hole opened in the ice sheet and she was dragged head-first into the freezing meltwater. Trapped hopelessly beneath eight inches of ice, she was slowly freezing to death.

Normally your core body temperature is 37C but with immersion in ice-cold water, this plummets rapidly. Below 35C, the body enters the state of hypothermia, characterised by shivering and pale skin. Below 30C, most victims will lose consciousness and, when body temperature drops to 25C, cardiac arrest will almost certainly occur.

Although Bågenholm’s friends immediately called for aid, it would take an hour and a half for a mountain rescue helicopter to reach their location. After 40 minutes of desperate struggling, Bågenholm’s body went limp. Shortly afterwards her heart stopped.

Following cardiac arrest, the body enters a state known as “downtime”. This is the twilight zone in which the process of dying begins. Normally within a few minutes of downtime, without immediate medical intervention, death will follow.

By the time Bågenholm was brought to the University Hospital of North Norway in Tromso, her heart had stopped for well over two hours. Her core temperature had plunged to 13.7C. She was in every sense clinically dead.

However, in Norway, there has been an old saying for the past three decades that you’re never dead until you’re warm and dead. Mads Gilbert is the head of emergency medicine at the hospital and, from experience, he knew that there was a slim chance the extreme cold had actually kept her alive.

“Over the last 28 years, there have been 34 victims of accidental hypothermia with cardiac arrest who were rewarmed on cardiopulmonary bypass and 30% survived,” he said. “The key question is, are you cooled before you have the cardiac arrest or are you first having a circulatory arrest and then getting cooled?”

While lowering the body temperature will stop the heart, it also reduces the oxygen demand of the body and, in particular, the brain cells. If the vital organs have been sufficiently cooled before the cardiac arrest occurs, then the inevitable cell death from the lack of circulation will be postponed, buying emergency services an extra time window to try and save the person’s life.

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