Going into sleep for month and then waking up just in time to land on Mars (or) You are under an emergency after an accident, falling into cardiac arrest and suddenly you are frozen until doctors repair you!
Doesn’t that sounds fascinating? Indeed it is just like it appears and its possible very soon we all gonna be experiencing it.
Exactly how hibernation works and why only certain animals do it remain great mysteries for biologists, but the last few years have seen some huge strides in our understanding of this phenomenon. One fact has become increasingly clear: natural human hibernation isn’t just a possibility, it’s a reality. We just need to figure out how to trigger hibernation states when and where we want to.
Hibernation is just the best known of a bunch of different metabolic processes that allow organisms to enter a dormant state. What sets hibernation apart is the precise changes that go on in the animal’s body during its dormancy period. Animals use the late summer and autumn months to build up lots of surplus body fat, which it can then slowly burn off during the winter.
During the hibernation period, animals drop their heart rate to as little as 5% of normal. This in turn causes their body temperature to also substantially decrease. Internal temperatures in the hibernating ground squirrels can drop to just below freezing, at 32 degrees Fahrenheit. Animals spend days or weeks slowly burning off their stored fat, effectively suspending all other biological processes until spring arrives, although animals do occasionally wake up for brief periods during their hibernation cycle.
Suspended animation, the ability to set a person’s biological processes on hold, has long been a staple of science fiction. Interest in the field blossomed in the 1950s as a direct consequence of the space race. Nasa poured money into biological research to see if humans might be placed in a state of artificial preservation. In this state, it was hoped, astronauts could be protected from the dangerous cosmic rays zapping through space. Sleeping your way to the stars also meant carrying far less food, water and oxygen, making the ultimate long-haul flight more practical.
One recipient of that funding was a young James Lovelock. The scientist would dunk hamsters into ice baths until their bodies froze. Once he could no longer detect a heartbeat, he would reanimate them by placing a hot teaspoon against their chest (in later experiments, Lovelock warmed to the space-age theme by building a microwave gun out of spare radio parts to more gently revive his test subjects). These experiments on the flexibility of life would set him on the path to his most famous work, the “Gaia hypothesis” of the world as a living super-organism.
Adventurous as they were, these early experiments did not progress beyond the animal stage, and astronauts were never frozen and revived with hot spoons. The idea of transforming people into inanimate bars of flesh for long-distance space travel remained in the realm of science fiction. Nasa’s interest tailed off with the end of the space race, but the seeds planted by Lovelock and his colleagues continued to grow.
Of course, it’s not that simple. Hypothermia is dangerous. Your body wants to be warm and will fight to remain that way. Throughout your life, it will maintain a fairly constant temperature of around 37C. This requires great effort. Your body must perform countless constant adjustments to balance heat production with heat lost to the environment, working to keep your temperature within a narrow band. If it drops too low, your blood is shunted away from the exposed skin and gathers in your central torso while you shiver and huddle under blankets. The effects of more severe cold are disastrous. At a body temperature of around 33C – just four degrees below normal – your heartbeat begins to flutter. At 25C, there’s a risk it will stop altogether. And even if you survive hypothermia, warming you up again can cause extensive kidney damage.
Today, scientists/biologists is searching for platelets, which are essential for blood clotting to prevent bleeding. Hibernating animals avoid getting blood clots despite their lack of activity, an ability that comes down partly to a curious change in the hypothermic body: as they cool, platelets disappear from the blood. Nobody yet knows where they go, but their prompt reappearance on rewarming has scientists convinced that they are preserved somewhere in the body, rather than being absorbed and later re synthesised. Surprisingly, this change also happens even in non-hibernators, including rats and – occasionally – human victims of hypothermia.
Knowing how hibernators control these changes in their blood could have immediate and far-reaching benefits for us. As well as improving our ability to survive hypothermia and cold suspended-animation states, stripping the blood of white blood cells could prevent the aseptic sepsis caused by heart–lung machines, in which activation of blood cells as they pass through the life-support equipment triggers a body-wide immunological reaction. Transplant organs, often chilled for transport, would also benefit from better cryoprotection. And we could increase the shelf-life of our blood stocks – we still haven’t figured out how to store donated blood platelets at low temperatures, so blood donations can only be kept a week before they must be used or thrown away due to the risk of bacterial infection.
Some of his surgeons will already be familiar with hypothermic techniques, having routinely chilled patients to the low 30s or high 20s. For procedures that require zero blood flow, cardiac surgeons will even cool patients to around 15C, the point at which their heart stops.
n the future, emergency preservation and resuscitation could be extended to those suffering heart attacks or exposure to poisons, or any critical care situation where time is a factor. “Cooling is the most powerful way of suppressing metabolism we have,” says a Researcher, “If we can either decrease the needs of the tissues or improve oxygen delivery to the tissues then everything will be okay.” And also hibernation opens up our long ranged space travels with having to experience less of the effects on our body and without getting tired, and waking up as if we reached the farthest in no time.