Many of you may have heard that there will be the first attempted head transplant performed in the next couple years. Surgeon Sergio Canavero announced his groundbreaking and highly controversial procedure in 2016. Since then his procedure has been subject to many modifications and delays. Beyond the realm of its probability, the scope of this procedure raises a huge array of physiological and ethical issues.
The procedure was originally set to be performed on Valery Spiridonov whom was diagnosed with Werdnig-Hoffmann Disease. This disease breaks down muscles and kills nerve cells in the brain and spinal cord (Whittaker, 2017). Valery allegedly withdrew from the procedure after discrepancies arose regarding the success of the procedure. The procedure will now take place in China next year and will be performed on a yet unidentified patient. Canavero is confident in his ability to perform the procedure after successfully transplanting the heads of mice, rats and dogs.
The procedure will involve first cooling down both bodies to slow down the metabolic rate and increase the window of decreased perfusion. This is a common practice amongst cardiac and brain surgeons. Next, the major blood vessels will be disconnected in the patient's neck and will be connected from the patient's head to the donor's body. Once vasculature has been re-established, the spinal cord will be severed and connected to the donor's body using poly polyethylene glycol which is casually referred to as a type of nerve glue. Stem cells or olfactory ensheathing cells may be introduced to the spinal cord as well in order to promote neurological growth. Once the spinal cord has been connected the body will be placed into an induced coma in order to allow for the body to heal without any movement from the patient.
Some important questions to ask are how this procedure applies to the ethical values of health care and what the physiological implications will be. In the case of Valery Spirdonov the patient was diagnosed with a progressive terminal disease so the benefit would be to prolong his life. Medical professionals range from being skeptical to terrified at the attempt to perform such a procedure (Bowler, 2017). It might be considered that given Valery’s fate, an attempt at life, whatever the odds would prove to be an improvement. However, scientists who have witnessed similar procedures in the past are calling this highly unethical and one doctor states that there are things far worse than death (Bowler, 2017).
Ultimately the patient will end up being a volunteer and their own autonomy will dictate their participation. Whether this procedure will be beneficial will depend upon the short-term and long-term outcomes of the procedure. The potential for doing harm to the patient is highly likely according to many medical experts (Whittaker, 2017). Justice would need to take into account that this procedure involves another person's body. The origins of this body would need to be incredibly regulated in order to respect the autonomy of the previous body owner and ensure that non-malfeasance is maintained. It is also important to know that an organ donor can save up to 8 lives and improve or benefit an additional 50 lives through eye and skin donation. All of these available resources would instead be delegated to one person. Lastly, we should consider what this would mean for the future of medicine. Currently in the United States people are plagued with seeking quick fixes to medical disorders instead of addressing the issue. Obesity is treated with bariatric surgery and liposuction instead of with diet and exercise. Cardiovascular disease, smoking, and other lifestyle diseases are treated proactively instead of preventatively. If proven highly successful, could a body transplant one day fall in line with these procedures and how would this affect society as a whole?
References
. LiveOnNY. (n.d.). Retrieved from http://www.liveonny.org/about-donation/quick-facts-about-donation/
Bowler, J. (n.d.). Head Transplant Surgeon Says He's Successfully Reattached The Spinal Cords of a Bunch More Animals. Retrieved from https://www.sciencealert.com/controversial-head-transplants-have-reportedly-been-performed-on-a-bunch-more-animals
HEAVEN: The head anastomosis venture Project outline for the first human head transplantation with spinal linkage (GEMINI). (n.d.). Retrieved from http://surgicalneurologyint.com/surgicalint-articles/heaven-the-head-anastomosis-venture-project-outline-for-the-first-human-head-transplantation-with-spinal-linkage-gemini/
Martin@alan_p_martin, A. (2017, September 25). Human head transplant delayed: Controversial procedure may not take place until 2018. Retrieved from http://www.alphr.com/science/1001145/human-head-transplant
Whittaker, B. (2017, July 13). New California law prohibits all cellphone use while driving. Retrieved from http://www.ksbw.com/article/new-california-law-prohibits-all-cellphone-use-while-driving/4096079
Along with the regulation required for the securement of the donor body, I also wonder about the feasibility of acquiring a body that is completely compatible with life. I am imagining that the donor would have needed to die from head injuries, specifically, in order to ensure that the remaining body is in good enough condition to be used for a head transplant. So even if the procedure proves to be successful, I feel that its overall helpfulness would be ultimately limited by the availability of donor bodies that meet a very tight criteria.
ReplyDeleteThat is a very good point Halimah. The donor will definitely be difficult to find. Apparently they have a body set up and state that it is classified as brain dead but otherwise healthy. Exactly how you described.
Deletehttp://www.dailymail.co.uk/health/article-3721986/Patient-set-undergo-world-s-human-head-transplant-says-Dr-Frankenstein-reveal-details-operation-month.html
This comment has been removed by the author.
ReplyDeleteI had a similar thought Halimah! There is a lot of discussion about the recipient but not as much about the donor. Do they need the donor to be alive at the time of transfer? If so, how does the ethics of terminating a life come into play? Would people in comas with "intact" bodies be targeted? There are some serious ethical concerns here, especially concerning the donor.
ReplyDeleteAdditionally, in a "traditional" transplant, there are many factors to account for to avoid organ rejection; I would imagine there are moreso here. Would age play a role in connecting (possibly) older neurons to younger organs? I also did a little research into nerve graft/transfer, and it seems like the technology is there to reconstruct neural circuits; however, many of the instances I read about, the nerves were donated from another part of the body within the same person. Although nerves function under the same mechanisms (as we are learning in class), I wonder if there may be some sort of miscommunication when a brain and spinal cord are attached to a completely new body. Where will the spinal cord be severed? Which nerves will be from donor vs. recipient? Where is the best place to join them (closer to the spinal cord vs closer to the innervated organs)? What other considerations come into play when discussing joining whole body system versus simply donating an organ?
These are really great points Melanie. I could not find an exact location for where the spinal cord would be cut. In one report it looks like around C3 or C4. There does seem to be some method to this idea. It appears that the cervical nerves superior to the position all innervate and preform cranial functions. I would also assume that the patient would constantly have to take immunosuppressant medication in order to for the head to not reject the body. To me, just reattaching the cord would be like removing every cable from the back of a computer server and then randomly plugging them back in. It would be like that only times a billion as there are approximately 100 billion neurons in the spinal cord. As for ethics, I and many other medical experts believe that Canavero is severally lacking in this department.
Deletehttps://www.a3bs.com/spinal-nerves-chart-vr1621l-3b-scientific,p_1380_2746.html
Should the answer to terminal neurological disease be head transplant every time? No, probably not - for all reasons and considerations mentioned. But the bigger question here is how this technology will contribute to the future and, quite frankly, the golden age of neurological discovery. The manipulation of nervous tissue is without doubt risky and can have severe consequences. The success of this transplant utilizing poly polyethylene glycol as "brain glue" could open the door to potential treatments of seemingly irreversible brain and spinal cord damage.
ReplyDeleteStudies are already being conducted on rats to test these possibilities using very similar compounds. Intravenous use of this substance could contribute to integrity of neuronal membranes following damage to a particular area (Koob et. al., 2005). The application of this technology along with neuroglia support cells may allow a radical surgery such as this transplant to be successful which would highlight the potential advancements within this field of medicine in a profound way (Kettenman et. al., 2011). However, surely the ethics behind the procedure are convoluted and vast. These considerations should always be taken into account and thoroughly assessed from all parties involved. That goes without saying...
Kettenmann, H., & Verkhratsky, A. (2011). Neuroglia, der lebende Nervenkitt. Fortschritte der Neurologie · Psychiatrie, 79(10), 588-597. doi:10.1055/s-0031-1281704
Koob, A.O., Duerstock, B.S., Babbs, C.F., Sun, Y., & Borgens, R.B. Journal of Neurotrauma. October 2005, 22(10): 1092-1111. https://doi.org/10.1089/neu.2005.22.1092
I couldn't have said it better myself. The practical use for polyethylene glycol is all the rage amidst the neurological community. I think that it will have extremely beneficial applications in the future of medicine. However, it is only a glue not a neurological "cure all" elixir and the way that Canavero is using it might be consider negligent to say the least.
DeleteThis is a very interesting topic. As mentioned above it could be very beneficial in understanding the advancing technology and being able to apply it in other aspects of medicine. Also as mentioned above there are a lot of ethical problems that could come from this.
ReplyDeleteThe biggest ethical issue for me is non-malfeasance, to do no harm (Ekstrand,2016). It could affect the recipient in many ways. Yes, the recipient is trying to use the donor’s body to prolong their life but there are so many things that can go wrong with transplants and that is before adding in multiple organs in the transplant. The head and body could reject the one another (Zhaung, 2016). The neurons used to assist growing new nervous tissue could not take in a human body and if that occurred the person would have no way to control the autonomic nervous system leading to death.If the body doesn't work the same way for the recipient as theirs previously did it could cause emotional stress.
It could also be discussed how as a community we are not ready for this. If this is completed how are records kept of people who have the same finger prints, and the same identifiable body markings and who are they considered the donor or the recipient? How will it affect the people in the community that may have know the donor and see the familiar body? There could also be undiscovered medical issues in the donor body that could appear later and then the recipient is again dealing with additional medical issues. Our bodies have their own time clocks, so adding in different levels of maturing organs could cause issues with levels of hormones released. There are just so many other parts to a head transplant that could cause problems; I do not believe we are ready to take this step. I do think that the knowledge that is used so far to the thought process of this should be used in other areas of the medical field because it is very advanced and beneficial.
Ekstrand, J.D., Ekstrand, M.D.: First do no harm: Considering and minimizing harm in recommender systems designed for engendering health. In: Engendering Health Workshop at the RecSys 2016 Conference (2016)
Zhuang, Q., Liu,Q., Divito,S. (2016)Graft-infiltrating host dendritic cells play a key role in organ transplant rejection. Nature Communications,(12623). Doi:10.1038/ncomms12623 (2016)
The picture I had in my mind when I first thought about this head transplant happening was Frankenstein. Will doctors focus on matching the skin-tones of the donor and recipient? How likely is the patient to be able to live a normal life after said transplant? Will major scarring in the neck area be an issue both medically and aesthetically? What is the likelihood that their disease just comes back in their "new body"? This brings up a plethora of questions on top of ethical issues on top of questions including Biological vs. Psychological Continuity. Who will this person be after the transplant? It's also worrying to me to that in the case that things go wrong which seems to be very likely with the length and complexity of the surgery, the possible loss of a human life due to experimental medicine as well as the possible loss of an entire body that as you mentioned above could possibly be used to help or save 50 other people in need. I agree with you that in we need to know more. I don't think it's worth the risk.
ReplyDeletePascalev, A., Pascalev, M. & Giordano, J. Neuroethics (2016) 9: 15. https://doi.org/10.1007/s12152-015-9245-4
https://doi.org/10.1007/s12152-015-9245-4