Head Case.

I’m going to start with a warning: it’s probably not best to read this post if you don’t want to hear about decapitation and animal experimentation.

But for those of you who remain intrigued … big news in the medical world: Italian surgeon, Sergio Canavero, is proposing to carry out the world’s first human head transplant by 2017, and is saying that he believes there is 90% chance of success.

Just to clarify a head transplant involves decapitating a human, and placing the entire head onto a different body.  It is not a brain transplant, which would involve removing the brain from one person and putting into the skull of another. Nor is it a full body transplant… that would basically be the same thing as a brain transplant because you’re retaining the skull and everything else.

It is, as you can imagine, rather tricky.

Head transplants have actually been attempted before on monkeys and dogs. The experiments carried out on monkeys involved decapitating the head and then reattaching it. The monkeys regained consciousness, but were quadriplegics, and apparently they woke up screaming. Given that they had not consented to the operation, this is hardly surprising… what is surprising is that their vocal chords still worked.

(Honestly, this is making me feel sick just writing about it. I know every new surgical procedure gets tested on animal first, and then hundreds of thousands of lives are saved/ improved as a result, and I’m aware I’m a hypocrite because I wouldn’t refuse surgery that had been carried out on animals first. But it doesn’t change the fact that if you dress it in a frock and call it science, it’s still torture for the animal.)

The dog experiment was slightly different.  In this instance, surgeons took an already healthy dog, and attached a second head to it. Both dogs regained consciousness, and retained distinct personalities. Unfortunately the second dog was unable to eat, and they both died.

All of the subjects of these experiments died shortly after their operations, and I suspect that the people behind these experiments weren’t thinking of long term recovery, but more, “Hmmn I wonder what would happen if…”

That Sergio Canavero is predicting a 90% chance of success is astounding. Limb transplants are generally more prone to failure than organ transplants for a couple of reasons:

  1. The skin is the body’s largest defense organ, it is designed to reject foreign matter, e.g. someone else’s skin.
  2. It’s more arduous connecting all the vessels and nerves to a whole new limb than it is to one organ, that makes, sensation, movement, and maintaining blood flow really difficult.

A head is not a limb.. but I’d say it’s an extremity.  The brain is the exception to the “organs are easier to transplant’ rule  (well of course it would be) apparently because it’s harder to rewire from the brainstem and connect all the vessels around the brain than it is to connect the spinal cord and neck tissues.. I bet there’s also issues with keeping blood supply going to the brain.  Anyhoo there’s probably more stumbling blocks than that but alas, I am not a medical professional, just a person with internet access and an opinion.

Perhaps Canavero is exaggerating in order to persuade the medical community to get behind him, the operation is going to cost around 15 million dollars, he needs all the support he can get. He has also stated that he will be responsible for attaching the spinal cord only… which means he needs to get a team of surgeons to commit themselves to the project, he can’t do it alone.

Perhaps though, Canavero’s definition of a successful procedure is not to have full bodily function, but to be able to survive.

The subject of the operation, is a 30 year old Russian man, Valery Spiridonov. Whilst this operation is causing a massive broohahah in the scientific community – Canavero is being labeled reckless and crazy, and his motives/ sanity are being questioned – Spiridonov’s reason to volunteer is clear. He suffers from Werdnig-Hoffman disease, which is Spinal Muscular Atrophy. 10% of people with this disease make it to adulthood, most die within the first few years. As the disease takes it hold, it causes muscle weakness so severe that it inhibits movement, eating, breathing, and swallowing amongst other functions. If you search for a picture of Spiridonov, it seems amazing that he is still able to maneuver in his electric wheelchair, and is not confined to a bed and on life support with breathing and feeding tubes, his body appears so twisted and small that it doesn’t look like it would be able to contain even partially functioning lungs and GI tract. The first thought I had was: will he live long enough to have the operation?

You can see how ‘success’ is a relative term.

It’s easy to be suspicious of Canavero, to view him as the hubristic, mad scientist stereotype: playing with lives, and reaping fame and glory.

But oh my gosh… what if it works?

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