Assuming that you had unlimited wealth, and you could decide exactly when the head was going to come off the living person, how long could current medical science keep it alive? What things would we need? I am not medically knowledgable so my guess would be: some way to reduce the trauma of the event, a way to supply oxygen to the brain, and a way to feed the brain nutrients. Of course this would be no enjoyable life - but dopers, can it be done for any appreciable time?
So your question has some complications to it. The main one for me would be defining alive. If you mean alive and conscious, I think you could maybe keep it going for a short period of time. If you are talking about keeping it so that there is some recognizable wave form coming from the brain, perhaps a longer.
You are exactly correct in what you’re assumptions except for one. You must keep nutrients to the brain, you must keep oxygenated blood flowing to the brain, and you must remove any waste that the brain produces. The brain is the only organ in the head you really need to be worried about. It certainly contains a lot more than just the brain, but for anything interesting to happen, you are going to need that to function, and it is going to be the most difficult aspect of the process. If you think about that, there are pretty much four systems that we must recreate artificially to keep a brain functioning. You blood would have to stay circulating. Normally this would of course be the function of the heart but sadly that falls below the limitation of the neck. This would not be extremely difficult to design in order to last a few moments–long term, you would have trouble keep blood from clotting around the machine and then those clots breaking off (embolization) and going to the brain and killing it by lodging into some of the small blood vessels.
Then you would have to keep oxygen flowing to the blood. This is going to be your limiting factor–we have not yet designed a synthetic lung yet. Having said that, you could try expose it to air before it is pumped and this system could possibly work. Again, this is going to be the limiting factor as you will not be able fully replicate the human lung, and you are going to cause clot formation.
Further, you need to keep nutrients going to the brain. That would be glucose (many other things but for simplicity). You would have to list all of those and make sure they are in the blood before it heads to the brain. you also need to make sure they in the proper concentrations in the brain.
The next function would be to remove the waste from the brain. There are two ways this could be carried out, one would be a modern day dialysis machine which is expensive. Or you could use this infinite wealth and just buy a ton of blood and pump that to the brain. It would have to be whole blood and there could not be any antigens in the plasma of any of the donors or the blood would react to itself as it mixed. (this is what happens when you give an A+ person B+ blood for example)
Obviously, you would want to cut of the head (which is morally wrong) surgically. You would want all of the blood that you send to the head to go via the common carotids (this would keep all tissue in the head supplied with blood). This would be your only access to the head. This is because you don’t need breathe to go thru the mouth or nose as you are treating the blood with another route.
If you were extremely precise, and used a great deal of money, on the first attempt, I think you could keep a brain conscious for a few minutes. You could keep the tissue alive for around an hour. Remember that the brain requires oxygen continuously or its cells self-terminate. The next big problem, is that there is not much reason to remove someone’s head and keep it alive if they are still living; we have evolved in a very complex manner so as to work with the rest of our bodies.
I imaging you would start by putting the “patient” on a heart-lung machine connected to a dialysis machine and some kind of nutrient server. Then you would, piece-by-piece, seal off and remove parts of the body. You would have to re-connect the vessels into and out of the neck into some kind of manifold. It’s hard to see how you wouldn’t eventually run into trouble, where you’d have dangley bits of tissue on the sides that you couldn’t get blood to.
Yeah sorry, i didnt even consider a heart-lung machine. I guess that would work as would synthetic lungs but they tell us those are limited time only. I don’t know what the max time to use for either is…
Edward, I’m curious what you mean about dangley bits of tissue on the side?
Ted Williams’s head is cryonically frozen yet is still alive. He died in 2002. He was a great baseball player for the Boston Red Sox. His head was severed from his body moments before his death. When the lab workers unfreeze his head for periodic maintenance purposes they have short baseball and fishing related conversations with Mr Williams. His head rests in Inverness, Florida.
Steve Jobs sold Pixar to Disney in return for access to the technology that they use to keep Walt’s head alive. Ironically, the software is incompatible with a mac and he’s powered by Microsoft. If you look very closely, you can see his head in a bell jar in one of the remote corners of the It’s A Small World ride. Fittingly, it was outsourced to the China section.
And, before White and Demikhov, Sergei Brukhonenko with colleague S.I. Tchetchulin.
They didn’t go as far as transplanting severed dog heads onto dog bodies lacking heads, but they did work to keep a severed head alive by obtaining the vasculature and lungs of a second dog and connecting the severed head to these “donor” organs via the “autojektor.” Experiments deemed successful took about 7 to 9 hours, most of which was devoted to the surgery itself. The final 2 or 3 hours were used for taking physiological and behavioral measurements from the isolated head. (Several years ago, when the short film “Experiments in the Revival of Organisms” surfaced on the internet, I read the two original papers from 1929 as well as three related papers from 1929 and 1934.)
