More Than You Ever Wanted to Know About.... Clinically Induced Death
A little hypothermia never hurt anyone. In fact, it could save your life – mild hypothermia, that is. Think of it as induced hibernation. Hibernating animals survive long, harsh winters simply because of the effects cold temperatures have on the body's defense mechanisms: capillaries constrict and send blood to vital organs; and metabolism slows, which further protects the heart and brain, since a slower metabolism produces fewer demands on the organs and reduces the need for oxygen.
Hibernating squirrels can even go without oxygen for up to six hours due to their suppressed metabolism. Arctic ground squirrels can hibernate for nine months with their body temperature reaching as low as 27 degrees Fahrenheit without freezing and, more importantly, without dying.
Although we as humans have not been endowed with the gift of annual hibernation like arctic squirrels, it seems that we have made our own version; or rather, scientists have found one: hypothermia – life-threatening, no doubt, but also life-preserving. Consider it suspended animation – think of Tom Cruise in the movie Vanilla Sky – only on a much smaller time scale, probably no more than a few hours, and without the erotic love scenes or emotional glitches, and much colder.
Think of falling through ice into a lake. Imagine yourself treading water in the biting cold and then slipping under. Emergency rescue crews find you an hour later, but they are too late. Your vital signs have flat-lined – no heartbeat, no brain activity; your lungs have even closed up because of the cold. If you could, you would call yourself clinically dead, because you are. If by some miracle you did regain consciousness, you wouldn't be ‘you' anymore, but more like a vegetable. But with the permission of your family, doctors hook you up to a heart-lung machine, restore a heartbeat, and slowly warm your body, which amazingly enough had gone into a hibernation-like mode. You are one of the dozens to experience this phenomenon – recovering without brain damage. Scientists don't call it resurrection. They call it resuscitation science. But you were clinically dead…
The line between life and death is blurred even more when it comes to induced hibernation – a mild hypothermic state produced in patients undergoing difficult surgeries or experiencing cardiac arrest. This procedure, usually achieved with ice packs or injections of cold saline solution, preserves the life of the patient. It allows patients to survive with minimal chance of brain damage in the midst of sub-par or even non-existent oxygen levels, because their low body temperature – usually about 92 degrees Fahrenheit or lower – has significantly slowed their metabolism. Often, in surgeries for life-threatening brain aneurisms, patients are cooled to the point of clinical death, with the blood drained from their body in order to effectively perform the surgery. If necessary, even potassium chloride, the chemical used in death row injections, is used to stop the beating of the heart. For a few brief hours, these patients are not alive.
Many even experience what has become known as a “near-death experience” – floating above their body in the operating room and watching the procedure, feeling content and free of pain. But if death can be reversed…If death can be reversed…the only certainty left in life is taxes, and even that has loopholes…
Recent studies have revealed that death isn't what it used to be. Not only is this new science of resuscitation leading doctors to redefine death; they're revising when it happens. Doctors used to believe that cell death occurred after cells were deprived of oxygen for more than five minutes. They have found, however, that it does not actually occur until hours later and the reason most resuscitations fail is because, after five minutes of oxygen deprivation, cells die when the oxygen supply is resumed. This death does not just happen passively; cells actually initiate their own death. Only patients placed in a mild hypothermic state are able to recover after that window of five minutes because of their low metabolic rate.
So were you really brought back from the dead after being pulled out of that lake and resuscitated? Or was that just a catchy headline that sucked you in? It seems like death has gotten lost, buried, laid out on an operating table and drained of meaning, amended with a new definition. Actually, according to the revised – yes, revised! – understanding of death, you weren't dead yet.