New Nanomed device: Replace Blood
ChrisPhoenix writes "Robert Freitas and I have published a paper on a rather aggressive nanomedical device that lines your blood vessels and replaces the blood. The paper covers benefits, requirements, installation, and more, with tons of medical information from Robert's amazing bank of knowledge. It's almost a megabyte and has 587 references. You can find it at The Journal of Evolution and Technology.
Vasculoid: A Personal Nanomedical Appliance to Replace Human Blood.
Robert A. Freitas Jr. and Christopher J. Phoenix
ABSTRACT
The vasculoid is a single, complex, multisegmented nanotechnological medical robotic system capable of duplicating all essential thermal and biochemical transport functions of the blood, including circulation of respiratory gases, glucose, hormones, cytokines, waste products, and cellular components. This nanorobotic system, a very aggressive and physiologically intrusive macroscale nanomedical device comprised of ~500 trillion stored or active individual nanorobots, weighs ~2 kg and consumes from 30-200 watts of power in the basic human model, depending on activity level. The vasculoid system conforms to the shape of existing blood vessels and serves as a complete replacement for natural blood. This paper presents a preliminary theoretical scaling analysis including transport capacity, thermal conduction, control and biocompatibility considerations, along with a hypothetical installation scenario and a description of some useful optional equipment. A discussion of repair procedures and various applications of the personal vasculoid appliance is deferred to subsequent papers.
(I'll be doing a Friday night SIG on this at the upcoming Senior Associate Gathering.)"
April 26th, 2002 at 12:45 AM
Wonderful work but…
What would the poets do if there were no more hearts? Call me old fashioned, but I would mourn the loss of my heartbeat.
April 29th, 2002 at 10:54 AM
a couple more benefits
This is relatively trivial compared to preventing metastasis and cardiovascular disease, but a vasculoid system such as this should make it much easier to do the kinds of diagnostics for which one now normally needs to have blood drawn. An external instrument could communicate with the vasculoid system by any of a number of non-intrusive means: light thru the outer few layers of skin, mechanical Morse-code-like tapping, maybe radio. These methods could be used for interventions as well as diagnosis, but in that case the communication channels should be cryptographically controlled. (Otherwise assassination by vasculoid reprogramming could become common.)
The other thought that occurs to me, while even more trivial, is of great interest to lots of people. A vasculoid system should allow for rapid healthy weight loss. Excess blood glucose and insulin could be dumped, causing stored fat to come out of storage and also get dumped, or be consumed in cell metabolism.
April 29th, 2002 at 12:33 PM
Re:a couple more benefits
The other thought that occurs to me, while even more trivial, is of great interest to lots of people. A vasculoid system should allow for rapid healthy weight loss. Excess blood glucose and insulin could be dumped, causing stored fat to come out of storage and also get dumped, or be consumed in cell metabolism.
Now, THAT caught my attention. Weight loss and I don't have to sweat or drink funny chemicals advertised on talk radio? Sign me up.
Seriously, I don't know if that would be trivial. "They" keep saying that obesity is a leading cause of sickness in the US blah blah blah. If you could eliminate obesity, you'd be freeing up a healthcare funds for other uses.
Patent that process and advertise on .. Talk Radio and you'll make a bundle.
April 29th, 2002 at 4:49 PM
Re:a couple more benefits
Will, I think you need to go read the paper in detail. You said, "This is relatively trivial compared to preventing metastasis and cardiovascular disease" — but the vasculoid does prevent metastasis and cardiovascular disease!
You can't die of a heart attack because the heart no longer pumps blood. You can't die from a stroke because the vasculoid carefully delivers quantities of nutrients to specific areas. It wouldn't deliver more nutrients to areas that suddenly suffered from leaky vessel walls. It would most likely transport more clotting factors to such an area. Finally you can't die from metastases because the vasculoid wouldn't transport cells that are "abnormal" or shouldn't be undergoing transport in an adult body.
I've examined the current causes of death and as far as I can determine vasculoid eliminates about 80% of them.
April 29th, 2002 at 10:37 PM
Re:a couple more benefits
You said, "This is relatively trivial compared to preventing metastasis and cardiovascular disease" — but the vasculoid does prevent metastasis and cardiovascular disease!
I was aware of those benefits. I was saying that blood-test diagnostics and weight loss are lesser benefits, but still ones that people would find very interesting. I did skim the paper, but in terms of getting up to speed quickly, it was handier to go back to Chris's original sci.nanotech posts. (Google groups: roboblood)
April 29th, 2002 at 10:39 PM
Re:a couple more benefits
I see now that my grammar was unclear. The "this" in my first sentence referred to the diagnostics, not the vasculoid. Mea culpa, I'll master my native language one of these days.
April 30th, 2002 at 5:41 AM
Re:a couple more benefits
The benefits versus the major premature causes of death are quite clear to me as well.
In spite of the paper's own conservative estimates, I think there could be large scale benefits upon eventual widespread acceptance, if an optimized system had reduced energy requirements. That is, if you needed to eat less, breathe less and waste less, the earth (and presumably space) could support a larger population. What I'm not clear about is whether the lack of heart activity, reduced kidney operation (etc.) have already been factored in to the energy consumption estimates.
If so, why not shoot for a complete cell replacement strategy instead? That is, implant artificial cells that behave just like the natural ones (they consume, divide, differentiate, react, interface, etc.), except far less fragile, and once they've all been replaced, then you can throw heat tolerance and other things out the window and run marathon sprints:)
April 30th, 2002 at 1:17 PM
Re:a couple more benefits
Chris and Robert discussed this to some extent at the Senior Associates meeting. Obviously whole nanoreplacement bodies are feasible. But that is going to require many more kinds of nanorobots. Vasculoid already requires at least 11 types (plates; gas, water, glucose, protein, lipid, and "other" tankers; docking bays; cellular boxcars (perhaps 3 types); cellulocks and vasculocytes). There are something on the order of 300 different cell types in the body. A study of a complete nanobody replacement of the depth of the vasculoid paper would be one or more volumes of documentation.
The paper is already so large that few will read it in detail. It isn't worth the effort to produce a full body replacement study when there are probably less than 100 people in the world who currently have the knowledge base needed to allow them to read such a document and provide useful criticism. The vasculoid paper in essense throws down the glove to get people to realize the changes that are coming. Most people will simply either believe that it is possible or dismiss it as impossible without bothering to educate themselves in more detail. Until this situation changes, anything more complex doesn't seem to be worth the time needed to produce something as complete as the vasculoid paper.
Regarding lesser energy use, you could probably reduce things by an order of magnitude but then you are up against the power requirements of the neurons. When you start discussing using nano-bush-trees (using Moravec's approach) to replace neurons with their nano equivalents you really start freaking people out because you are into outloading or uploading technology. Until people figure out that radical lifespan extension is possible and comprehend that "bodies" limit their ultimate longevity (because nano or not they are vulnerable to catastrophies) and further realize there is a real need for outloading or uploading if they want indefinite lifespans, I don't think most people will be comfortable with nanobrains.
April 30th, 2002 at 7:13 PM
Re:a couple more benefits
Are there any benefits for the immunity system? Will blood still carry virii like the HIV. I know little about medicine, but I'm wondering if this provides any hope.
April 30th, 2002 at 7:19 PM
Re:a couple more benefits
Given that the style of solution proposed in the Vasculoid paper would already need quite a lot of other successful implementations of nanotech, it would seem likely to me that you could just boxcar or tanker stemcells to microfactories (or microbreweries if you will) to create the necessary cells as required, on-site. So hopefully you wouldn't need 300+ types of rotor to sort through the different cell types. Certainly having cells available around the body would help with quicker repair work after external damage. Even if the paper is a little bit of overkill to a basic reader like myself, I also think it's worth it's creation in order to show that this scenario is not impossible, merely difficult. I like the idea of people looking at solutions rather than purely focusing on the risks associated with nanotech.
April 30th, 2002 at 7:26 PM
Re:a couple more benefits
It would seem to me to be the perfect tool to eliminate or limit known virii. Anything that normally passes through blood, and is identifiable through some sort of marker, should be stoppable.
As mentioned in the paper, the example of cancer cells being identifiable and limited would be a similar scenario. If the vasculoid only allows passage of recognised cells then anything at a cellular size would would be stopped. The problem would be sub-cellular stuff like mycobacteria – although I imagine you could have markers to identify them as well.
The other benefits mentioned are quicker and more accurate dosage of white cells to specific sites of infection.
May 1st, 2002 at 11:04 AM
Re:a couple more benefits
Section 1.2 of the paper discusses the benefits. In general both viruses and bacteria that are normally transmitted via the blood would be unable to do so. Paul is correct that intracellular viruses or bacteria would be more difficult targets to detect and eliminate. Robert suggests that infected cells could be detected in his paper but this presumes that evidence for the infection is produced on the surface of the cells being transported. That tends to depend on the specific combination of MHC alleles a person has and the specific amino acids found in the proteins produced by the viral or bacterial DNA/RNA. Vasculoid would also not eliminate infections of cells exposed directly to the environment. The epithelial cells of the lung and skin infections come to mind. It still leaves it up to the immune system to survey and eliminate those cells.
May 3rd, 2002 at 12:58 AM
Vulnerabilities (was Re:a couple more benefits)
Well, they did devote a great deal of thought to proving that risks can be limited (e.g. reversibility). Notwithstanding, these are the vulnerabilities that I see:
It seems to me that embarking on the first step of a multiple-stage full cell replacement (the control/diagnosis step) would actually be a simpler path to take and require less advanced nanotech than an intricately engineered transport system like the vasculoid. In later stages, once enough cells have been replaced and improved, upgrades like the vasculoid can be brought into effect neatly. Moreover, I think cell replacement can be done gradually enough so that few are offended at any one point. Until full inorganic replacement, the human cell interface should be kept as the compatibility standard and vendor licenses held to it. Accountability is also easier if there is one vendor per cell.