How Cold Can a Living Body Get?

Years ago, doctors went to extreme measures to save a woman with the lowest-ever body temperature on record.


In May 1999, three junior doctors, Anna Bågenholm, Torvind Næsheim and Marie Falkenberg, were out skiing off-piste in the Kjolen Mountains of Northern Norway, near the town of Narvik. It was a beautiful evening, one of the first days of eternal sunshine at the start of the Arctic summer and the skiing had been good. They found themselves descending into a shaded gully called the Morkhala, a place they knew well and had a good covering of snow even late in the season. All three were expert skiers and Anna began her run confidently.

But during the descent Anna unexpectedly lost control. Torvind and Marie watched from afar as she tumbled headlong onto a thick layer of ice covering a mountain stream. Anna slid across it on her back and then fell through a hole into the water. Her head and chest became trapped beneath the frozen surface. Her clothes began to soak, their extra weight carrying her deeper, dragging her downstream with the current and further beneath the ice.

Torvind and Marie arrived at the spot just in time to grab her ski boots, stopping her from vanishing under the lip of the ice. Anna was lying face up with her mouth and nose out of the water, in an air pocket. She continued to struggle, freezing, in the Arctic stream.

None of the three could have been in any doubt about the seriousness of the situation. Anna was trapped; her clothes soaked with ice-cold water; the stream carrying heat away from her body. Even in those first minutes her core temperature was beginning to plunge. Torvind called for help on his mobile phone, explaining the life-and-death predicament to the dispatcher.

As doctors, Torvind, Anna, and Marie had many friends and colleagues in the rescue services—the dispatcher among them. Firm in the faith that they would make every effort to expedite an emergency rescue helicopter or a mountain rescue team, Torvind returned to help keep Anna from slipping under the ice.

Forty minutes after first becoming trapped, Anna’s desperate thrashing stopped and her body went limp. The hypothermia, now profound enough to anaesthetise her brain, would soon stop her heart. Another forty minutes passed before rescuers from the bottom of the mountain arrived, carrying with them a more substantial shovel, with a pointed tip that was finally able to break through the covering of ice.

Eighty minutes had passed since Anna had first fallen into the water and her body was pulled clear of the stream limp and blue. She had stopped breathing and was without a pulse.

We call what follows 'downtime'—the period from the moment of cardiac arrest until the point at which spontaneous circulation and breathing can be restored. In that interval, the process of dying begins. Before that comes the 'crash'. If your physiology has crashed, the processes that keep you alive have stopped working.

As the resuscitation effort began on Anna’s body in the shadow of those Norwegian mountains, the challenge she faced looked insurmountable. She had been without a pulse for a long time and her core temperature was perhaps more than 20 degrees lower than it should have been. Torvind insisted that they continue their resuscitation attempts. Just before 8:00 p.m., more than an hour and a half after first falling into the stream, Anna was winched onto a helicopter. The struggle to save her  life became a desperate scramble.

When the crew touched down at Tromso University Hospital, Anna’s heart had not beaten for at least two hours. Her core temperature was measured at 56.7 degrees Fahrenheit—42 degrees below her normal core, and lower at that point than any surviving patient in recorded medical history. This was genuine terra incognita. Any attempt to resuscitate Anna further could only proceed in the knowledge that in similar situations past medical teams had always failed.

But the team at Tromso decided to continue. Despite the amount of time that had passed since Anna’s heart had first stopped, there was still the glimmer of a hope that the terrible cold might also have protected and preserved her brain.

Mads Gilbert, the anesthetist leading the resuscitation effort, moved Anna directly to the operating theater. He knew that raising her temperature at this point was going to be a massive challenge. Raising the whole body through those 42 missing degrees would take an enormous amount of energy—equivalent to the boiling of dozens of kettles of water.

To do this quickly and without harming Anna in the process, Mads knew she would have to be established on a heart-lung bypass machine; the sort of device normally reserved for open heart surgery. By removing her chilled blood, circulating it in the bypass machine, heating and then returning it to Anna’s lifeless body, they could raise her core temperature rapidly.

They wasted no time. Thirty minutes after being established on the heart-lung bypass machine, Anna’s core temperature had increased, reaching 87.8 degrees Fahrenheit. The heart stuttered at first, unable to regain its own essential rhythm. But eventually electricity once again began to flow through the muscle of her heart, and this was followed by waves of contraction. At around 4 p.m. it started to beat independently for the first time in at least three hours.

Miraculously, Anna survived, opening her eyes for the first time after just 12 days. But she found herself paralyzed from the neck down, waking alive but quadriplegic. Later she grew angry, asking the doctors at Tromso why they had been so determined to keep her alive. Together the costs of her helicopter rescue, resuscitation and admission to the intensive-care unit added up to many tens of thousands of dollars.

All of this was done for a woman who awoke alive but with a body that no longer appeared to work. This was the best that anyone might have dared hope for given how cold she’d been and how long she’d gone without a pulse. Had their endeavors truly been worth it? Should they have proceeded with the resuscitation at all?

But Anna’s paralyzed body did not remain that way. It wasn't an irreversible injury to her spinal cord that left her unable to move, as is so often the case after traumatic injuries. It was instead her peripheral nerves, damaged by the extremes of cold, which had failed. Slowly but surely these nerves and her flaccid muscles began to recover and regain their function.

The nerves recovered most slowly in her extremities. Initially she could not use her arms and legs at all. Though after six weeks she was ready for discharge from the hospital, she could not go home. Anna spent another four months in a rehabilitation unit, slowly growing in strength and learning how to move once more. It was a slow process but eventually she was able to go home. Medicine had brought her this far and where it stopped her determination had to take over.

It would ultimately take six hard years of rehabilitation in all, but eventually Anna was well enough to ski again; well enough to return to complete her training as a doctor. She later specialized in radiology in Tromso, in the hospital that had dared to save her life. Doctors exploited Anna Bågenholm's profound hypothermia to successfully resuscitate her against seemingly impossible odds. While her survival occurred in the context of an accident, she is living proof that extremes can cure as well as kill.

This post is adapted from Kevin Fong's Extreme Medicine: How Exploration Transformed Medicine in the Twentieth Century.