Health and Medicine: Case Reports

Current discussion surrounding Dr. Canavero’s human head transplant proposal

By Carly Cheung, Microbiology, ’17

Author’s Note:

“The controversial topic of a human head transplant caught me by surprise when I read about it in the news. I was curious about the psychological, immunological, and technical complications of this procedure. After researching it, I became more knowledgeable and open-minded towards it.”

In 2013, physician Dr. Sergio Canavero proposed to attempt the world’s first human head transplant as a last treatment option for patients with diseases that infect their body, but leave their brains healthy. The volunteer is Valery Spiridinov, a 31-year old man suffering from Werdnig-Hoffman disease, a disorder characterized by muscle atrophy. An outline of the procedure was published in the International Journal of Surgery.

Canavero’s paper first describes the procedure of a head-body transplant performed by Dr. Robert White in a Rhesus monkey in the 1970’s. The monkey appeared normal after the transplant in all measures, but survived for only 8 days due to the lack of technology to re-connect the spinal cord. Now, nearly five decades later, Canavero’s protocol includes more advanced technology. First, an especially sharp blade is used to sever the recipient’s head from his body. A brain-dead donor’s body, whose immunotype is matched to the recipient, is selected. After the recipient’s head is drained of blood, it, along with the spinal cord of the donor’s body, is chilled to temperatures of 12-15οC. Studies have shown the ability to restore functions of the brain with arrested circulatory blood flow without neurological damage within 45 minutes. The rest of the recipient’s body, however, is kept at normal temperature to maintain organ functions. Appropriate monitoring of the organs, as well as injection of anesthesia and antibiotics, is applied. Spinal cord, vessels, and veins of head and body are subsequently sewn together within 1-2 minutes. A solution that facilitates in membrane fusion and acts as a neuroprotectant is applied through an IV into the bloodstream. Immunosuppressant drugs, identical to those taken by organ transplant patients, are used. The patient is provided with psychological therapy during recovery.

Two reviews by Furr and colleagues published in 2017 provided additional methods for the most difficult part of the surgery: re-connection of the spinal cord. The methods were successful in patients who suffer from spinal injuries. Additionally, it emphasized the maintenance of an intact blood-brain barrier as critical in preventing access of immunoregulatory cells to the brain, which lowers the chances of the body rejecting the brain. They also proposed manipulating the donor body’s bone marrow cell precursors of immune cells to recognize antigens of the face and head. The psychological risks the patient would encounter are currently unknown because a self-body dissonance as large as the one that the patient will experience has never been encountered. Although, enhancement of life quality reported by patients who underwent face transplants indicated a possible positive outcome. More research on the brain immunology axis was suggested. Additionally, opponents in the bioethics department pointed to the inability to provide Mr. Spiridinov with the full risks of the procedure, to ensure informed consent, as a large red flag.

A successful head transplant has enormous implications on the possibilities provided by science and technology in the future. Currently, 800 physicians and health-care professionals have joined Dr. Canavero’s team. The surgery is scheduled to take place in December 2017.

References

Canavero, S. (2013). HEAVEN: The head anastomosis venture Project outline for the first human head transplantation with spinal linkage (GEMINI). Surgical Neurology International, 4(Suppl 1), S335–S342. http://doi.org/10.4103/2152-7806.113444

M.A. Hardy, et al., The immunologic considerations in human head transplantation, International Journal of Surgery (2017), http://dx.doi.org/10.1016/j.ijsu.2017.01.084

  1. Furr, et al., Surgical, ethical, and psychosocial considerations in human head transplantation, International Journal of Surgery (2017),

http://dx.doi.org/10.1016/j.ijsu.2017.01.077