Let’s also imagine that, unfortunately, you live far away from an organization that offers these services. In that case, especially if you die suddenly, the chances of having a preservation team get out to you in a timely manner (within <4-12 or even <24 hours) seem quite small.
But what about embalmers? Don’t they already pump aldehyde-containing solutions through the blood vessels of recently deceased people? And aren’t there already a bunch of them in lots of places in the world? Couldn’t they possibly do the initial preservation themselves, thus stabilizing the structure of the brain/body and thereby addressing one of the key problems related to access to preservation services?
This topic has been a hotly debated one over the years in the field of preservation/biostasis/cryonics. Of course, I will not end the debate in this one essay. But what I will try to do is:
(a) make the case that using the services of embalmers actually does make sense in some circumstances, and then
(b) discuss some practicalities of how people can use the services of remote embalmers to access preservation services with Sparks (where, as a form of disclosure if you were not already aware, I work as a Research Scientist).
Is the use of commercial embalming fluids a good idea for structural brain preservation? The extant evidence is pretty unclear, but it suggests that cellular structure is preserved, as would be expected by the fact that embalming fluids use formaldehyde as their key component
The problem with evaluating the usefulness of embalming fluids for brain or whole body preservation is a common one in this field, which is that nobody has really bothered to study it directly, probably because they just don’t care very much (and why would they?).
Instead, the main literature we can draw upon is mostly the forensic pathology literature. Here, the goal is to exhume or otherwise examine an already embalmed body, e.g. to figure out to what extent a person had pathological changes in their body or brain prior to their death.
A few such studies are here, here, here, and here. What this literature generally finds is that the histologic structure is reasonably well preserved. There are occasionally some artifacts reported, such as myelin splitting. However, these types of artifacts are commonly also seen in human tissue preserved via more conventional fixatives, so they could also be explained by postmortem changes.
Of course, preserving enough structure to make a pathologic diagnosis does not mean that the information in the fine neural structure likely required for future revival will still be present.
Obviously, there are a ton of variables one needs to consider when evaluating such a literature, such as publication bias (maybe investigators are more likely to publish when the preservation is surprisingly good?). And the direct evidence on brain ultrastructural preservation in particular is pretty minimal/non-existent. But my personal/current read of the situation is that the formaldehyde in the embalming fluid is doing its expected aldehyde thing of preserving tissue structure really well.
If neutral buffered formalin can be acquired and used instead of commercial embalming fluids, the reasoning chain becomes much stronger that embalming methods may be effective
(*Pedantic note: Actually, neutral buffered formalin is a type of embalming fluid, as it is described in the literature. But in my experience, it’s not one that funeral home embalmers usually have. They would probably need to buy it. Luckily, it seems to be fairly shelf-stable at room temperature. It can even be used in recycled format (not that I’m recommending that for preservation purposes! … absent a zombie misaligned AI near-apocalypse destroying supply chains). So I’m distinguishing “commercial embalming fluids” from aldehyde formulations more commonly used in anatomy or neuroscience, like neutral buffered formalin, paraformaldehyde, and/or glutaraldehyde.)
Insausti et al 2023 is one of the best brain banking papers ever in terms of the ultrastructural preservation they reported:
They perfused through both common carotid arteries, with the cannulas directed towards the head. Then they perfused the rest of the body through the left common carotid artery with the cannula directed towards the heart. This is pretty similar to the type of vascular access that embalmers use. (They used 4% paraformaldehyde for perfusing the brain, but other research suggests that 10% neutral buffered formalin — which contains approximately 4% formaldehyde — can lead to similar results.)
Data from our laboratory suggests that the use of washout solution is not necessary to remove blood clots — formalin can be perfused right away. This substantially simplifies the procedure for embalmers (and, in my opinion, makes it likely to be more effective as well).
Basically, if embalmers use a standard fixative such as 10% neutral buffered formalin, cannulate the bilateral common carotid arteries, perfuse toward the head, and do this all in a timely fashion (ASAP), then I think the results of Insausti et al 2023 and other brain banking studies suggest that the brain preservation quality is likely to be quite good.
Is embalming alone a good long-term preservation strategy?
No, not in my opinion. The brain/body should be secondarily immersed in fixative solution as well, so that regions not adequately reached by arterial perfusion are preserved to the best extent possible, and also to minimize oxidative damage and prevent dehydration. But, the evidence suggests that embalming alone is decent enough in the short-term during transport to a facility for long-term preservation procedures.
OK, so I think that this whole embalming thing is a reasonable idea. How can I or my friends/loved ones actually access this, practically speaking?
As far as I know, Sparks is currently the only preservation organization in the world that offers brain-only or whole body preservation following conventional embalming performed by a remote funeral professional.
(The Cryonics Institute historically advised for remote funeral directors to do vascular washout before shipping patients to their facility. However, they no longer recommend this, apparently because they found that remote washout could paradoxically make subsequent cryoprotectant perfusion at their facility more difficult.)
The approach of cryonics organizations is fundamentally different than ours, because we use aldehyde fixation. The main reason we do this is because it provides better validated structural preservation, but we realized later that another advantage of using aldehyde preservation is that it also allows for embalmers to perform the initial procedure remotely and then ship the body to us for long-term preservation.
At Sparks, our standard service within the continental US is to deploy our own preservation personnel, and we do not currently offer remote embalming as a lower cost alternative here (we do, however, offer Financial Aid).
However, for people who live in Alaska, Hawaii, or other countries (e.g. Canada), we offer a few different international preservation options.
The relevant option to this discussion is to have a local funeral director or embalmer perform arterial embalming, followed by shipment of the whole body to our headquarters in Salem, Oregon. We would then perform subsequent preservation procedures and place either the person’s brain or the whole body into long-term storage, depending on what the individual prefers.
The cost for the brain preservation service is $7500, or $6000 with our long-term membership discount. Whole body preservation is also available for an additional fee. These fees do not include the cost of the local embalming or transportation services, which will obviously vary by location and the service provider, and would be paid directly to them.
Of course, whether this option is available in a given place depends on the local laws (sadly, long-term preservation after legal death is illegal or functionally illegal in some places) and whether there are qualified professionals available. Countries vary widely in the extent to which they have a robust culture of embalming.
We recommend contacting us well in advance so that we can help coordinate this as well as we can.
What is the main potential problem with this approach?
If you accept this paradigm in general (which many people do not!), then the main problem is that embalmers might not reliably perform the procedure quickly enough after a person legally dies. This is why we recommend making arrangements with us and/or a local funeral professional in advance, rather than trying to coordinate everything very late.
Do you have a page with recommendations for a local embalmer?
(Cross-posted at the Sparks Newsletter)
Let’s imagine that you think that preservation after legal death with the goal of future revival may actually be able to preserve important information that you care about, such as long-term memories.
Let’s also imagine that, unfortunately, you live far away from an organization that offers these services. In that case, especially if you die suddenly, the chances of having a preservation team get out to you in a timely manner (within <4-12 or even <24 hours) seem quite small.
But what about embalmers? Don’t they already pump aldehyde-containing solutions through the blood vessels of recently deceased people? And aren’t there already a bunch of them in lots of places in the world? Couldn’t they possibly do the initial preservation themselves, thus stabilizing the structure of the brain/body and thereby addressing one of the key problems related to access to preservation services?
This topic has been a hotly debated one over the years in the field of preservation/biostasis/cryonics. Of course, I will not end the debate in this one essay. But what I will try to do is:
(a) make the case that using the services of embalmers actually does make sense in some circumstances, and then
(b) discuss some practicalities of how people can use the services of remote embalmers to access preservation services with Sparks (where, as a form of disclosure if you were not already aware, I work as a Research Scientist).
Is the use of commercial embalming fluids a good idea for structural brain preservation? The extant evidence is pretty unclear, but it suggests that cellular structure is preserved, as would be expected by the fact that embalming fluids use formaldehyde as their key component
The problem with evaluating the usefulness of embalming fluids for brain or whole body preservation is a common one in this field, which is that nobody has really bothered to study it directly, probably because they just don’t care very much (and why would they?).
Instead, the main literature we can draw upon is mostly the forensic pathology literature. Here, the goal is to exhume or otherwise examine an already embalmed body, e.g. to figure out to what extent a person had pathological changes in their body or brain prior to their death.
A few such studies are here, here, here, and here. What this literature generally finds is that the histologic structure is reasonably well preserved. There are occasionally some artifacts reported, such as myelin splitting. However, these types of artifacts are commonly also seen in human tissue preserved via more conventional fixatives, so they could also be explained by postmortem changes.
Of course, preserving enough structure to make a pathologic diagnosis does not mean that the information in the fine neural structure likely required for future revival will still be present.
Obviously, there are a ton of variables one needs to consider when evaluating such a literature, such as publication bias (maybe investigators are more likely to publish when the preservation is surprisingly good?). And the direct evidence on brain ultrastructural preservation in particular is pretty minimal/non-existent. But my personal/current read of the situation is that the formaldehyde in the embalming fluid is doing its expected aldehyde thing of preserving tissue structure really well.
If neutral buffered formalin can be acquired and used instead of commercial embalming fluids, the reasoning chain becomes much stronger that embalming methods may be effective
(*Pedantic note: Actually, neutral buffered formalin is a type of embalming fluid, as it is described in the literature. But in my experience, it’s not one that funeral home embalmers usually have. They would probably need to buy it. Luckily, it seems to be fairly shelf-stable at room temperature. It can even be used in recycled format (not that I’m recommending that for preservation purposes! … absent a
zombiemisaligned AI near-apocalypse destroying supply chains). So I’m distinguishing “commercial embalming fluids” from aldehyde formulations more commonly used in anatomy or neuroscience, like neutral buffered formalin, paraformaldehyde, and/or glutaraldehyde.)Insausti et al 2023 is one of the best brain banking papers ever in terms of the ultrastructural preservation they reported:
https://pubmed.ncbi.nlm.nih.gov/37034833/
They perfused through both common carotid arteries, with the cannulas directed towards the head. Then they perfused the rest of the body through the left common carotid artery with the cannula directed towards the heart. This is pretty similar to the type of vascular access that embalmers use. (They used 4% paraformaldehyde for perfusing the brain, but other research suggests that 10% neutral buffered formalin — which contains approximately 4% formaldehyde — can lead to similar results.)
Data from our laboratory suggests that the use of washout solution is not necessary to remove blood clots — formalin can be perfused right away. This substantially simplifies the procedure for embalmers (and, in my opinion, makes it likely to be more effective as well).
Basically, if embalmers use a standard fixative such as 10% neutral buffered formalin, cannulate the bilateral common carotid arteries, perfuse toward the head, and do this all in a timely fashion (ASAP), then I think the results of Insausti et al 2023 and other brain banking studies suggest that the brain preservation quality is likely to be quite good.
Is embalming alone a good long-term preservation strategy?
No, not in my opinion. The brain/body should be secondarily immersed in fixative solution as well, so that regions not adequately reached by arterial perfusion are preserved to the best extent possible, and also to minimize oxidative damage and prevent dehydration. But, the evidence suggests that embalming alone is decent enough in the short-term during transport to a facility for long-term preservation procedures.
OK, so I think that this whole embalming thing is a reasonable idea. How can I or my friends/loved ones actually access this, practically speaking?
As far as I know, Sparks is currently the only preservation organization in the world that offers brain-only or whole body preservation following conventional embalming performed by a remote funeral professional.
(The Cryonics Institute historically advised for remote funeral directors to do vascular washout before shipping patients to their facility. However, they no longer recommend this, apparently because they found that remote washout could paradoxically make subsequent cryoprotectant perfusion at their facility more difficult.)
The approach of cryonics organizations is fundamentally different than ours, because we use aldehyde fixation. The main reason we do this is because it provides better validated structural preservation, but we realized later that another advantage of using aldehyde preservation is that it also allows for embalmers to perform the initial procedure remotely and then ship the body to us for long-term preservation.
At Sparks, our standard service within the continental US is to deploy our own preservation personnel, and we do not currently offer remote embalming as a lower cost alternative here (we do, however, offer Financial Aid).
However, for people who live in Alaska, Hawaii, or other countries (e.g. Canada), we offer a few different international preservation options.
The relevant option to this discussion is to have a local funeral director or embalmer perform arterial embalming, followed by shipment of the whole body to our headquarters in Salem, Oregon. We would then perform subsequent preservation procedures and place either the person’s brain or the whole body into long-term storage, depending on what the individual prefers.
The cost for the brain preservation service is $7500, or $6000 with our long-term membership discount. Whole body preservation is also available for an additional fee. These fees do not include the cost of the local embalming or transportation services, which will obviously vary by location and the service provider, and would be paid directly to them.
Of course, whether this option is available in a given place depends on the local laws (sadly, long-term preservation after legal death is illegal or functionally illegal in some places) and whether there are qualified professionals available. Countries vary widely in the extent to which they have a robust culture of embalming.
We recommend contacting us well in advance so that we can help coordinate this as well as we can.
What is the main potential problem with this approach?
If you accept this paradigm in general (which many people do not!), then the main problem is that embalmers might not reliably perform the procedure quickly enough after a person legally dies. This is why we recommend making arrangements with us and/or a local funeral professional in advance, rather than trying to coordinate everything very late.
Do you have a page with recommendations for a local embalmer?
Yes, here (pdf).
How can I sign up?
Here! It can be done online. There are no upfront costs to sign up.
I have additional questions. Who can I talk to?
Please contact us by phone at 503-585-2781 or by email at hello@sparksbrain.org.