Head transplant? Are we that advanced to do it? When you hear about it you may thing “are we in a Frankenstein movie?” Well we aren’t but you have to admit that would be cool. It looks like medicine evolved so much. Just think about the first discoveries ever made, how it all started. Maybe the next step will be the cure of cancer or who knows. (if you want to know more about the history of medicine check out the last post )
The first human head transplant will take place in December this year. This will be performed by an Italian neurosurgeon Sergio Canavero with a crew of 150 medics and about 80 of them would be surgeons.
But let’s start from the beginning. How it all started? Ever since the early 1900s, people have discussed the possibility of head transplant. However, at that time surgeons faced with many challenges. One of the main challenges in transplant surgery was reliable vessel anastomosis. Vascular surgeons struggled thinking how to cut and repair an injured vessel and subsequently restore blood flow without interrupting circulation. Bone, silver and gold, and absorbable material grafts were in use back then, but these materials gave uncertain and variable results in patients. A french surgeon, Dr. Alexis Carrel, was the one that changed these results by using a more reliable method of suturing severed vessels back together ( he used fine needles and extremely thin threads as suture and enlarged the severed vessel opening using three retaining sutures to form a triangular shape).
Attention!!! If you are a dog lover, the paragraph that follows may affect you so please skip to the next one.
In 1908, Dr. Alexis Carrel and Dr. Charles Guthrie, performed the first dog head transplant. They attached one dog’s head onto another dog’s neck, connecting arteries in such a way that blood flowed first to the decapitated head and then to the recipient head. The decapitated head was without blood flow for about 20 min, and while the dog demonstrated aural, visual, and cutaneous reflex movements early after the procedure, its condition soon deteriorated and it was euthanized after a few hours. The transplant failed. In 1954, Dr. Vladmir Demikhov also attempted a canine head transplant. Demikhov’s dogs demonstrated more functional capacity than Guthrie and Carrel’s dogs and were able to move, see, and lap up water. A step-by-step documentation of Demikhov’s protocol published in 1959 reveals how his team carefully preserved the blood supply to the lung and hearts of the donor dog:
First they made an incision at the base of the large dog’s neck, exposing the jugular vein, the aorta and a segment of the spinal column. Next they drilled two holes through the bony part of one vertebra and threaded two plastic strings, one red and one white, through each of the holes… Then he and Demikhov, deftly wielding the scalpel, needle and thread, proceeded with infinite pains to expose the small blood vessels, drawing a tight knot of thread around each one in turn as they carved gradually deeper into Shavka’s vitals. Finally Demikhov severed the spinal column.
Even though the rest of its body had been amputated from this dog, its head and forepaws still retained and used the lungs and heart. During the third phase of the transplantation, the main blood vessels of this dog’s head were connected with the corresponding vessels of the host dog. The longest that any dog survived this surgery was 29 days, also longer than Guthrie’s and Carrel’s dogs, but unfortunately most died within a few days.
Back to Dr. Sergio Canavero! For years he has been planning to attempt to perform the world’s first head transplant. The procedure that Dr. Canavero suggest is quite interesting. I think the best way to understand it, plus more, would be from Dr. Matthew Crocker, consultant neurosurgeon at St George’s Hospital, London. (check the video below)
If you don’t want to watch the video for particular reasons or if it doesn’t work, I will also write below the procedure.
Dr. Canavero will begin his attempt by cooling the volunteer’s body to 50 degrees fahrenheit and severing both his head and the brain dead donor’s head from their respective bodies and spinal cords. Polyethylene glycol will be used to connect the volunteer’s head with the spinal cord of the donor’s body. The plan is to induce the volunteer into a coma for 3 weeks while blood and new nerve networks rebuild in hopes that the body doesn’t reject the head—an inherent type of risk in all transplant procedures. In addition to the spine, patient’s head will also have to be reconnected to airways, the esophagus and blood vessels.
But like in any discovery there are pros and cons. Some believes that it will work and that the volunteer for it will be able to walk, to run, in other words to have a normal life. But others think that Canavero is just a charlatan, he just wants publicity and he is a crazy man if he thinks the surgery will be a succeed.
Probably one of the most appropriate response for the whole situation would be Michael Sarr’s response, he was a surgeon for 35 years. He said: “Granted, I’m retired,but what do you have when you die other than your reputation? I’m confident that at least in theory the operation will work. The science is there. I wouldn’t risk my reputation otherwise.” He continues: “Is Sergio Canavero a bit of a showboat? Yeah, he probably is. But you know, you might need a showboat. Somebody’s going to do this. And somebody has to do it first. And let me tell you, he’s taking a risk of his own. If this doesn’t work, he will be considered a charlatan for the rest of his life.”
In my opinion there are 50% chance for this surgery to be a success and 50% chance to not. Maybe, right now, we don’t know all the details behind it and probably we will never know everything. Why is Canavero so sure about it? Does he has a backup plan? What remains to be done? Well just to wait and see what’s going to happen in December. Will it be a success or a failure? Will this really happens or not?(comment below what do you think)
P.S. If I made you curious about the head transplant and you want to find more about it check it out Head Transplant 2017.