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The youngest person to be cryogenically preserved

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Re: The youngest person to be cryogenically preserved

#31

Post by toomuchtodo »

geographomics wrote: post #16
dahart wrote: post #10

Earlier quoted context omitted.

The serious answer is that resuscitation of cryopreserved humans is not currently possible and has never been done. We have no idea whether anything from the brain or the body is salvageable, nor whether starting sooner or later makes any difference. Perhaps one way to think about it is that cryopreservation is a modern alternative to a grave burial, and the thing most salvaged is the hope and memories in the family…

I agree. Resuscitation seems unlikely, given that the freezing process itself damages the tissues, as well as the degradation that has already happened post-mortem.

100 years from now is a long time for medical advancements. Would you imagine having an MRI or CT scan 100 years ago? Or that they'd induce hypothermia in an emergency room to stave off damage from cardiac arrest [1]?

[1] http://www.popsci.com/node/205352

Re: The youngest person to be cryogenically preserved

#32

Post by pen2l »

tptacek wrote: post #15
TazeTSchnitzel wrote: post #11

Has any living person ever had their heart intentionally stopped, been cryonically frozen, defrosted, and revived? Because if not, then we don't know if it works on people who aren't yet dead. And if we can't do that, what hope do we have for reviving the actually dead? (I'm aware in rare cases people have been massively cooled down and had their heart stopped for operations, but that's not quite the same.)

No.

Which question was that a 'no' to? (there were two questions in the post you're replying to)

Re: The youngest person to be cryogenically preserved

#33

Post by ggreer »

TazeTSchnitzel wrote: post #11

Has any living person ever had their heart intentionally stopped, been cryonically frozen, defrosted, and revived? Because if not, then we don't know if it works on people who aren't yet dead. And if we can't do that, what hope do we have for reviving the actually dead? (I'm aware in rare cases people have been massively cooled down and had their heart stopped for operations, but that's not quite the same.)

Well... the whole idea behind cryonics is that the people preserved with current technology can be revived/reconstructed with future technology. Asking for a full preservation & resuscitation today is demanding evidence that wouldn't exist even in the case that cryonics works.

That said, there is evidence available today. 21st Century Medicine is a company that does research on cryoprotectants. Their chief science officer is Greg Fahy, who co-invented the first method for cryopreserving embryos[1].

21st Century Medicine's primary goal is to research new ways of cryopreserving tissues. This is already useful for research and some tissue banking (embryos, corneas, etc). If improvements continue, it could allow for organ banking. But the brain is an organ, and cryopreservation technologies work quite well on it. For example, 21st Century Medicine can take a slice of a rat's hippocampus, cryopreserve it, and thaw it. Afterwards, it's still viable tissue.[2] This is very important, as the hippocampus is not only crucial for memory consolidation, but it's the part of the brain most vulnerable to ischemic damage (especially the CA1 region).

21st Century Medicine has also experimented with whole organs. They've taken a kidney from a rabbit, cryopreserved it, thawed it, and transplanted it back into the rabbit. Then, after removing the remaining kidney, the vitrified-and-thawed kidney kept the rabbit alive indefinitely. Alcor uses the same cryoprotectants as this experiment.

If cryonics works, this is exactly the sort of evidence you'd expect to see today. Granted, it probably won't work, but the expected value is positive.

1. Ice-free cryopreservation of mouse embryos at −196 °C by vitrification (http://www.nature.com/nature/journal/v313/n6003/abs/313573a0...)

2. Cryopreservation of rat hippocampal slices by vitrification (http://www.21cm.com/pdfs/hippo_published.pdf)

3. Physical and biological aspects of renal vitrification (http://www.21cm.com/pdfs/12FahyORG5-3%5B1%5D.pdf)

Re: The youngest person to be cryogenically preserved

#36

Post by qohen »

philjohn wrote: post #17
TazeTSchnitzel wrote: post #11

Has any living person ever had their heart intentionally stopped, been cryonically frozen, defrosted, and revived? Because if not, then we don't know if it works on people who aren't yet dead. And if we can't do that, what hope do we have for reviving the actually dead? (I'm aware in rare cases people have been massively cooled down and had their heart stopped for operations, but that's not quite the same.)

There's also some cases of people who's hearts had stopped after being caught outside in sub-zero temperatures being successfully revived with no adverse effects.

This isn't cryonics by any stretch, but doctors are seriously looking to put gunshot victims into suspended animation by drastically cooling them down so they can be worked on [0]:

When a shooting or stabbing victim goes into cardiac arrest due to massive bleeding, even the most heroic attempts at resuscitation fail 90 percent of the time. But a study to begin this month under the direction of Sam Tisherman and Patrick Kochanek at the University of Pittsburgh Medical Center Presbyterian Hospital will see if there's a better way: cooling the body after the heart has stopped beating, to the point where all other functioning virtually ceases as well.

By putting patients literally into a state of suspended animation—or "emergency preservation," as Tisherman calls it—the surgeons intend to preserve brain functioning long enough to close wounds that would otherwise be fatal.

[0] http://news.nationalgeographic.com/news/2014/04/140402-suspe...

Re: The youngest person to be cryogenically preserved

#37

Post by martin-adams »

I find cryogenics such a thought provoking field. If you're going to be frozen after death, you would probably want the restoration process to be fully mature before you are restored. But yet, someone has to go first (outside of shorter frozen trials).

But then again, who is to say that the restoration process will take the form of thawing out the brain. An advanced digital scanning technique could imprint the brain image onto an organic robot, thus making it possible to have many copies of the same person.

I also find the concept similar to the teleport. You may be the person who goes in, but are you the same person who comes out the other end? Indistinguishable from you, only you are not the observer of your own reality.

[Edit: A couple of really obvious grammatical errors]

Re: The youngest person to be cryogenically preserved

#38

Post by tim333 »

martin-adams wrote: post #37

I find cryogenics such a thought provoking field. If you're going to be frozen after death, you would probably want the restoration process to be fully mature before you are restored. But yet, someone has to go first (outside of shorter frozen trials). But then again, who is to say that the restoration process will take the form of thawing out the brain. An advanced digital scanning technique could imprint the brain…

>someone has to go first

Probably there'll be animal experimentation first. Then when Fido's still able to fetch they'll give humans a bash.

Re: The youngest person to be cryogenically preserved

#39

Post by jeremyjh »

martin-adams wrote: post #37

I find cryogenics such a thought provoking field. If you're going to be frozen after death, you would probably want the restoration process to be fully mature before you are restored. But yet, someone has to go first (outside of shorter frozen trials). But then again, who is to say that the restoration process will take the form of thawing out the brain. An advanced digital scanning technique could imprint the brain…

Only if the observer were some metaphysical being, rather than simply the inside view of a particular computation. If you reproduce the computation faithfully, you have reproduced the observer.

Re: The youngest person to be cryogenically preserved

#40

Post by tim333 »

DavideNL wrote: post #14
dahart wrote: post #9

Its impossible to imagine how hard it would be to lose a child, but I can imagine why that state of mind makes even the remotest glimmer of hope for reincarnation seem like a good idea. I thought This American Life's episode on cryonics was riveting, educational and fascinating. http://www.thisamericanlife.org/radio-archives/episode/354/m...

i agree, this is tasteless and should be forbidden in my opinion, the only one who should be able to decide if they want to be frozen and revived should be the person themselves.

It's impractical with kids any more than you can ask them if they want to be born.
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