Is it Possible to Revive a dead Person? See how cryopreservation can make it possible?

What would it be like for those people to wake up if we could cryogenically preserve them for years, if not centuries?  There are currently around 300 people on the verge of death in three facilities in the United States and Russia. They exist in a state of deep cooling known as cryopreservation, and fell asleep after their hearts stopped beating. Their brain tissues were suspended using an ice-free process called vitrification before they experienced true cell death.

All are legally dead, but if they could speak, they would most likely argue that their remains do not even qualify as dead bodies. They are, in a sense, just unconscious.

Chances are very low still there’s a hope

Nobody knows if these people can be revived, but an increasing number of the living seem to believe that uncertainty is preferable to the alternative. Cryonics waiting lists include approximately 1,250 people who are still legally alive, and new facilities are set to open in Oregon, Australia, and Europe in the near future.

Cryonicists believe that modern technology will one day enable them to resurrect the dead. But how likely is a second chance after a deep freeze?

One of the things which makes us person, it is said, is our awareness of our own mortality, and for nearly as long as we've known that we'll die, we've started to wonder about the possibility of getting up in the morning again.

"[Most] cryonicists will tell you two things. We obviously enjoy science fiction. "We're also optimists," says Dennis Kowalski, president of the Cryonics Institute, a non-profit based in Michigan and one of only a few companies in the world providing its services.

How the Cryonic Process Works?

When anyone  prepares to put their remains cryonically preserved after death, a medical team by the company cools the body with ice water and uses CPR and oxygen masks to oxygenate tissues of the body. The body is placed in an ice-cold container and flown to the cryonics facility. (A note about terminology: freezing a cadaver is cryonics, not cryogenics.) The science and engineering of super-low temperatures is known as cryogenics.)

At the cryonics facility, the body is placed on a machine that functions similarly to a heart-lung bypass machine, circulating blood and maintaining oxygenation. They inject a vitrification solution, which acts like antifreeze to keep the body's tissues from freezing and causing structural damage. The body is then slowly cooled to -320 °F in a liquid nitrogen vapor chamber. When the body is sufficiently chilled, it is transferred to a liquid nitrogen tank resembling a Thermos, where it will remain for the foreseeable future.

The bodies will be stored in such tanks for the period medical technology can revive them in future. According to Kowalski, this future technology will face three challenges: it will need to repair the damage caused by freezing, cure whatever ailment originally killed the subject, and reverse the ageing process so that the subject has a young, healthy body to enjoy in their second go-round. Nobody knows what that technology will look like; Kowalski's best guess is tissue engineering and molecular nanotechnology capable of repairing and replacing damaged tissues. 

At the end

Beyond the debate over what is possible or might be possible in the future, another question remains: even if you could be brought back, would you want to? After all, you'd be stranded in a strange world, cut off from everything that made your life worthwhile to begin with.

"You've got nothing to lose and everything to gain." Aside from some life insurance money. And it's worth it to me. It gives me peace of mind," says Kowalski, who, along with his wife and sons, has signed up for cryonic preservation. "Even if it doesn't work, we're still advancing science by determining what doesn't." And if it works, oh my God, we've just discovered a temporary cure for death."