No Longer The Stuff of Science Fiction, Suspended Animation May Find Real World Application Soon With Humans

Suspended animation has actually been around a long time, though not in humans. Many bacteria can go into a state called sporification, where they can last indefinitely. One such was brought back after 250 million years, a new World’s Oldest Creature record.  (This does, interestingly, provide a method for life, albeit bacterial, to travel from planet to planet.)

Human sperm, eggs, even fertilized ones, can be frozen and thawed later. Even success with eggs that had already begun replication has been reported.

But what about me? If I jump in a vat of liquid nitrogen (-321º), could I be frozen and preserved? There are a few technical difficulties with this at present, one of which is that water expands when cooled, and would pop all my cells. Not a good start.

Cryonics

But there is a field called cryonics that has worked through the problem of getting people into the vat of liquid nitrogen without popping all their cells. They first replace the cellular water with something akin to antifreeze, then pack the subject in dry ice, and finally the liquid nitrogen bath. Does this work? No one has been brought back yet. Will it ever work? Well, if so, not soon.

Why are we so pessimistic? So far, no one has managed to freeze and restore anything larger than a few cells. And this is not from lack of trying. A further problem, at least with humans, is that this procedure can only be applied to someone that has already died. Even if the patient was willing to “chill” before death, it isn’t allowed. And if this ‘isn’t allowed’ sounds like an old foggy’s concern for ethics, let me ask you to really think it through before brushing this issue aside. For those that, while still living, have ponied up the $200,000, a crew will scramble around upon their death, replacing blood, and performing all sorts of other improbable activities, in order to keep what’s left of them still alive, chilling you down until you can be deposited into the liquid nitrogen vat. The $200,000 covers long-term storage, which may be long term indeed.

So far, this doesn’t sound like much of a real world application. However, we’re getting there.

Real Suspended Animation

If we are willing to settle for something a little less than a Lazarus style reincarnation, we’ve definitely got something. Rather than freezing someone, why not just cool them down. Major surgery patients are routinely packed in ice now to do just that: to lower the metabolism and reduce the need for oxygenated blood.

This has been taken even further, with blood replaced by a cold saline (salt) solution, and the patient cooled down to around 50º. At this point, the patient is clinically dead, no heartbeat, no brain activity. The operation is performed, and warm blood restored. The survival rate is 90%, with no apparent loss of memory or mental function. The longest they have had someone out like this is around an hour.

No Oxygen?

If the loss in oxygen is abrupt, the respiration system goes seemingly haywire, and the victim dies. However, if the reduction is slow, the body seems to be able to somehow  adapt. The cells seem to shut down in a relatively ordinary manner, and can be revived.

Possibly there was just enough oxygen to keep the cells going. Another intriguing possibility: every cell in your body has a back-up system. In the absence of oxygen, a cell can generate energy by fermenting the sugar it has stored. This is inefficient, but perhaps generates enough energy to keep things ticking over.  You actually may use this backup energy generation frequently. If you exercise fairly vigorously, after a few minutes, you will start to feel a burn. This is because your cells are generating energy from fermentation. The burn is a waste product from the process: lactic acid. (N.B. we are simplifying here: lactic acid/lactate is also one of the brains favorite energy sources, it has a role in gluconeogenesis, and it has a backdoor back into the Krebs cycle, etc.)

Ice Isn’t the Only Way

Researchers have successfully put pigs and dogs into suspended animation using various techniques. They may chill the pig way down, but rather than replacing blood with cold saline, they have it breathe hydrogen sulfide (rotten eggs odor).. The pig appears to die. The heart stops and there is no measurable brain activity. The pig can remain like this for several hours. Then they reintroduce oxygen and the pig recovers, seemingly 100% intact. Other researchers use other methods, but the idea is the same. Slow the body first, then cut the oxygen.

There have been several mice experiments wherein the oxygen supply was replaced with hydrogen sulfide. The mice were ‘out’ for several hours, but all revived.

Humans?

It’s going to happen if it hasn’t already. The proposed use for this would be cases of severe accidents: gunshots, stabbings, etc.. In many such instances, victims die on the way to the hospital despite frantic lifesaving efforts. If the first responders put the victim into a state of suspended animation instead, they could take him to the hospital without further worry. He could be operated on in a proper operating room without all the drama. The surgeons could take their time, and the victim would obligingly chill till they were ready to operate.

UPMC Hospital in Pittsburgh is ready to try this as of 2014. No news so far.

What About Space Travel?

In the cold saline solution or hydrogen sulfide approaches, the cells are shut down, but not dead. They seem to still need some nutrition. So Animation isn’t really Suspended, just slowed way down. Maybe some variation of these techniques will prove to be useful tools. Researchers are currently keeping animals alive for several hours. Why not days, weeks, years? How rapidly would you age in such a state?