Growing up with cold Canadian winters means that we get to enjoy tobogganing, skiing, and other snowy activities. It also means that from a young age, we’re warned of the dangers of getting too cold.
Recently, I was teaching a First Aid course with the Red Cross, focusing on environmental emergencies like hypothermia and frostbite. Our textbook had detailed guides for prevention, recognition, and treatment – outlining exactly what to do, down to the colour of frostbitten skin and the severity of hypothermia. I wondered how the recommendations were so specific! Where does this information come from?
Well, it turns out these book chapters, along with the emergency response protocols for virtually every English-speaking provider of pre-hospital care worldwide, are written by none other than Professor Popsicle!
Dr. Gordon Giesbrecht is the world’s leading authority on hypothermia. He runs the Laboratory for Exercise and Environmental Medicine at the University of Manitoba, which studies human responses to exercise and cold environments through various extreme experiments. Dr. Giesbrecht often subs in as the test subject, giving him the famous nickname, “Professor Popsicle.”
Prior to Dr. Giesbrecht’s contributions, there was a large gap in the research — scientists hesitated to drop research participants body temperature below 35°C (normal is around 37°C), which barely constitutes as hypothermia. But with a mission to save more people from environmental emergencies and a willingness to put his body to the test, Dr. Giesbrecht dove right in. Literally. His research style involves leaping into frozen lakes, dunking into cold water baths, and even injecting ice water into his veins. As he puts it, “I’m the scientist who does things for real, to make sure I really know what I’m talking about.” Through these controlled experiments, Dr. Giesbrecht was the first to clinically describe the symptoms of severe hypothermia! One such symptom was that — contrary to what one would expect — people tend to stop shivering as their hypothermia worsens.
With the help of nine volunteers through the “Cold Water Boot Camp,” Dr. Giesbrecht developed the “1-10-1 principle” for surviving cold water immersion emergencies. Surprisingly, dropping these volunteers into freezing 6°C water did not induce hypothermia in mere minutes. Dr. Giesbrecht explains that it actually takes at least half an hour for hypothermia to develop. “Most people who die in cold water die either immediately or very shortly after. But they are not hypothermic” says Dr. Giesbrecht. What actually puts people in danger is panicking and aspirating water, which happens when you gasp and fill your lungs with water.
The 1-10-1 Principle describes the three critical phases of cold-water immersion. 1 — Cold Shock, during which you have one minute to keep calm and control your breathing, 10 — Cold Incapacitation, a 10-minute period where you can make meaningful movement before your muscles begin to freeze, and 1 — Hypothermia, which will take about one hour before making you unconscious. Knowing the phases of cold-water immersion allows people to maximize their chances of survival by self-rescuing and delaying hypothermia.
Arguably the most revolutionary finding from Dr. Giesbrecht’s research proved that immediate rewarming of cold patients would not send the body into shock. Prior to this finding, first responders would wait to rewarm patients rescued from the cold, fearing that immediate rewarming would put them at a greater risk. Thanks to Dr. Giesbrecht’s recommendations for rewarming, new protocols are now used by emergency responders across Canada. In fact, it’s what I was teaching in my First Aid class!
Giesbrecht’s experiments depended on the measurement of the body’s internal temperature taken using probes in the esophagus, the tube that connects the mouth to the stomach. Other experts in the field critiqued this measurement, claiming that most animal studies show a discrepancy between esophageal and heart temperatures. In true Professor Popsicle fashion, he responded by sending a catheter through a vein in his arm all the way to his own heart, then went hypothermic, proving that in cold emergencies, the human heart and esophageal temperatures drop in a parallel fashion. Dr. Giesbrecht’s lifesaving findings also include extensive research on vehicle submersions and other aspects of thermophysiology. You can read more or watch clips from Cold Water Boot Camp.
There you have it! We know how to “keep cool, but [not] freeze” all thanks to Professor Popsicle’s physiological experiments!