Technology & Medicine Mag-Robotics in Surgery/Transplantation

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Technology & Medicine Robotics in Surgery and Technology in Transplants Filippo Velonà

Ethics of Robotics in Surgery Robotics is something we have learned to live with through the years. New generations have learnt to live with it and eventually we will possibly become dependent on it, as we have now become dependent on the web. We are now starting to see the first robot waiters in restaurants and we have, with drones, given the ability to robots to kill.

For something to be potentially fatal to people, h o w e v e r, it doesn’t necessarily need guns and bombs; a surgical robot can do just as much damage if something goes wrong. It is for this reason that ethics about robots in general and later in surgery is such an important and at the same time difficult topic.

Commonly when talking about ethics in robotics three laws of robotics come up: a robot may not injure a human being or, through inaction, allow a human being to come to harm; a robot must obey orders given to it by human beings except where such orders would conflict with the First Law; and a robot must protect its own existence as long as such protection does

not conflict with the First or Second Law. These laws come from a novel written in 1942 by Isaac Asimov titled “Runaround”. (Spilmann and Sade 2014) These laws were referenced to autonomous robots, programmed to have a component functioning similarly to a brain. These laws were written almost 80 years ago and today we see we have already infringed them, with military robots, however we come to question, were these laws realistic? What if robots actually weren’t applied to the military and only to help in society to replace or help in jobs humans don’t want to do anymore or need help with. A surgical robot theoretically does just that.

Law number one states: a robot may not injure a human being or, through inaction, allow a human being to come to harm. In robotic surgery the robot does a job which a surgeon would otherwise do without it. Therefore, theoretically there is no added danger, if the machine works a p p r o p r i a t e l y. H o w e v e r some think that using robots

causes surgeons to be unprepared in traditional surgery. (Strong et al. 2014) This would mean that, through inaction, this robot may cause a human being to come to harm, by causing a surgeon’s incapacity to save a life through an operation later. This opinion, however, is heavily contrasted by those saying that the robot is just a tool, like others that surgery has used through the years. Surgical tools have existed since prehistoric times, evidence of surgical knife’s existence can be traced back to the Mesolithic which was 8000 years before Christ. Isn't the robot therefore just another tool that a surgeon can use to help his surgery, or is it such a drastic change that it may cause new surgeons to lose the ability to operate in traditional ways. The surgical robot differs from other surgical tools only in the way that it replaces the surgeon from actually working on the open body, this takes from the surgeon many senses, mostly tactile, causing him to rely only on sight. (Spilmann and Sade 2014)

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This could possibly result as a problem since traditional surgery relies hugely on this type of feedback, it is in fact this that causes the greatest criticisms to surgical robots.

Up to this point we are lacking in sufficient information to have an in depth analysis of this, and for this reason one of the priorities is to make sure all operations with new technologies are recorded, possibly as in depth as possible. As for now, we can conclude that, while new robotic surgery may demand more from those studying medicine, since it is something more they need to learn in addition to traditional surgery, as well as for already operating surgeons to get used to such a change in method, particularly the loss of touch, if handled appropriately and if kept together with traditional surgery could, now and even more in future improve and make more difficult or up till now impossible operations, possible. With all safety protocols in place and with both patients being favourable and surgeons agreeing to use this equipment, which they should only if they feel confident and have some experience in using it, a robotic surgeon may save a life, while not injuring or, through inaction cause a human being to come to harm.

Following through, law number two states: a robot must obey orders given to it by human beings except

where such orders would conflict with the First Law. (Spilmann and Sade 2014) The controversy of this law, and as we will see for the final one, is the fact it states that law number two may not be followed if law number one isn’t followed due to it.

This is to say that if, in this specific case, the surgeon, gives it the order to harm a patient, the robot won’t. This is particularly hard to do, in particular since the surgical robot, as we discussed previously, should eventually be seen as a tool, facilitating certain types of operations. If this is the case, however, if a human would command it to make a cut, which would kill the patient, the robot would do this. This, however, would be the exact same if a surgeon would be operating and therefore isn’t much of a concern. Where this law becomes an ethical concern regarding to surgical robots is in malfunctioning. A robot differs from other tools in the way that it actually gives motion itself, without the need for a surgeon’s movement. This of course is one of the reasons which makes this technology so innovative and so revolutionary, however it is very complex and has many parts that have to work in synchrony to give the surgeon the ability to operate and to make sure nothing goes wrong. If only one of these components fails, a patient may in fact come to harm. As well as harming a patient, going against the first law this would also cause the robot to break the

second law, by not respecting a command given to it by a human. For these two reasons, the absolute priority of a robotics company is to prevent malfunctions, though it is also an absolute priority of the surgeon to control that the robot is in perfect conditions to operate before and after surgery since it is him operating the robot and he must be totally conscious of the tool he is using and how it could react in different situations. Then again I think that it’s as important that someone trained to know what to do in case of emergency is in the operating room and would know what to do if something goes wrong to minimize the damage that could be done.

To conclude on this law we must acknowledge that, like other surgical tools it can’t go against the surgeon when commanded to do something wrong, and this keeps being the surgeon's responsibility, however it should not cause any additional harm through malfunctioning, which would cause it to disrespect a human’s command. This should be done through continuous inspections and controls, in educating surgeons on the use, and risks of the equipment and how to react and by making sure they know how to check the machine before surgery.

Finally, also the presence of someone in the operating room that should be trained to know what to do in case of emergency, is crucial.

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The third and last law we will analyse is: “and a robot must protect its own existence as long as such protection does not conflict with the First or Second Law.” (Spilmann and Sade 2014) Being this robot non-autonomous this law connects to the surgical robot in the safeguarding of the surgeon or resident working with the robot. To respect this law the surgeon always has to agree and know what he is doing, I think that it’s extremely important that a surgeon or resident knows that he always has the choice to not use the robot if he doesn’t feel comfortable with it. This might be forgotten because of the big advertising campaigns that hospitals who bought the equipment and manufactures have put in place, mostly to make up for the extreme costs of such machinery, a da Vinci robot costs up to 2 million dollars, it is obvious that the hospitals will try and make up for the money. It is important that a surgeon, or even more a resident, new to the world of surgery, is always aware that the priority of medicine and surgery is the safety and well being of the patient, meaning if a resident or surgeon has the minimal doubt that this can be assured through the use of the robot it’s important they do say this and decide how to proceed. Something else is that advertising is sometimes done using credentials from surgeons they have not approved usage of, and some specialty

organizations hold the surgeon responsible if this is incorrect, therefore they must check and be aware of how hospitals and companies use their data and material for advertising.

To follow this rule it is consequently important that surgeons are always aware of their right to choice and understand that some advertising, like outside off hospitals, is only done for the hospitals and manufacturer’s wants, since the manufacturer wants more data to advertise and the hospital to justify the costly apparatus. It is also very important they control how the hospital and manufacturer uses their data or feedback in advertising, since, if done wrong, it may be them who suffer the consequences.

operating room must have undergone training and know exactly what to do in case of various emergencies or malfunctioning.

-Finally and most importantly the surgeon or resident must know and remember it is always the patient who decides what he wants to undergo and while a surgeon may use his qualifications to give options or try and convince the patient, the patient’s wanting is always the main reason for a choice and to choose the equipment and procedure.

In conclusion, surgical robots are and could become even more a great innovation, with the potential to revolutionise surgery for how we know it.

Ethically, while it can be discussed, and data is lacking to make definitive conclusions it would respect moral codes. However, some rules must be obeyed, in particular: -The surgeon must always have and be aware he has the choice in using the robot, -The surgeon must receive the appropriate training in traditional surgery first, and then in robotic surgery, -The robot must always be controlled and both the surgeon and someone physically present in the 3

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First successful transplant (kidney)

Transplants Over 100 Years The history of transplantation develops mostly in the last 100 years or so. It is very complex and may to some appear useless when discussing the future of transplants. However, this history could be used as a scale, a scale to measure the time it may take for some changes to occur.

Transplantation reached its innovation peak between the 1950s and 1960s and lowered its rate of innovation significantly after 2005 or so.

What I find interesting and perhaps shocking is realising

that just 70 years ago, transplants didn’t exist, or rather, working transplants didn’t exist. Keeping this in mind, I think this field of medicine is one that will continue to improve day by day, and to understand how it may develop we must first understand its roots and history. To do this we will start by mentioning experiments done in the early 1900s but we will start a more detailed analysis from 1912, understanding and discussing Carrell’s work. We will then move on

from there up through to today. In the early 1900s all that was done were some vain attempts in saving humans dying from renal failure by the transplantation of kidneys from animals, like dogs or monkeys. Now we know this would have been impossible however up until that time it was unknown, having there been no attempts. In 1905 Edward Zim managed to restore sight to a blinded man. (history.com 2018)

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through a cornea transplant.

For the first actual studies, however, we will have to wait up to 1912. In 1912 Alexis Carell won the nobel prize for medicine following successful kidney transplants in dogs. He also discovered a way to connect blood vessels, of course crucial in transplant surgery, or at least applied it, since some say that he wasn’t the first to develop a suturing technique for vessels. Before the war, Carell also started some research on the reason for organ rejection however, not understanding it and forced to stop because of the war Carell moved on to work with Lindbergh to create what was the first machine perfusion. While this should have been used for open heart surgery, it was used as the first example of what now is used in most cases of organ preservation before implantation. Instead of using it to keep blood flow through the body during surgery, the pump was used to keep this circulation in the organ or tissue and it allowed for preservation up to three weeks. While at the time, being this prior to the actual possibility to transplant an organ, it wasn't as valuable, it later became a crucial piece of machinery, and now, one hundred years later, it’s still used and we are reflecting on how in future it may change the world of transplantation. In the 1930s, Leo Loeb conducted some studies regarding rejection. He discovered that in rats, the

rate of rejection depended on the genetic difference between the donor and the recipient. In addition he showed that the lymphocyte was involved. Due to a false claim regarding a “finer mechanism” all the discoveries were discredited and soon scientists forgot about their existence.

(Barker and Markmann 2013) An understanding of rejection is practically all that is missing to bring to working transplantation. During the years between 1933, where a Soviet surgeon attempted the first human transplant, and 1954, many experiments on humans were carried out, in some cases, by attempting methods to reduce rejection, the patient could even live up to 3 months with the transplanted organ before rejecting it, amount of time reached only when the donor was the mother of the patient. At this time, transplant success was still a more than remote p o s s i b i l i t y, t h e r e f o r e transplant experimentations were only done on patients who suffered of renal failure, that at the time had no other cure, and would cause the death of the patient either way. In 1950, urologist Lawler claimed one of his transplants as being successful, however while it did produce urine for a very brief amount of time, after a few months it was removed and was found to be shrunken. In this case, the

patient had an impaired renal function, however it wasn’t totally blocked, the patient then went on to live her life. While this wasn’t of scientific significance mediatically it was very pronounced and pushed other surgeons towards transplantation research.

During WW2 Peter Medawar together with Thomas Gibson re confirmed that homografts, transplants between same species, always failed. They also confirmed that this was because of an immunological rejection.

Later, they decided to study and attempt transplants on twin cattle, Gibson asked for the help of a junior colleague Billingham. From these experiments they discovered that homografts between twins always worked, even if they were different genders.

At the time they found this shocking. 14 months after these discoveries, Joseph Murray was the first patient to receive a successful kidney draft. This was accomplished by using his twin brother's kidney. While the fact that transplants between twins worked was well known the impact of this transplant was significant. In fact it took only one year for discoveries to show that in mice, if the immune system was weakened, the transplant could avoid rejection and be integrated in the body. While this was first done through radiation, it is the start to what has now developed in immunosuppressive drugs, 5

crucial to effective transplants. Tom Starzl revolutionized the world of transplantation when, at a conference between the best transplant surgeons, in which he came more as a wildcard than an actual participant, he showed the results of his immunosuppressive drugs.

These results were impressive, while other surgeons, using their methods to attempt immunosuppression had only 10% of patients living only up to or over 3 months, Starzl had more than 70% of his renal transplants patients live over the year. Following the conference Starzl’s chemical method of immunosuppression was adopted by most transplant surgeons, and allowed for much better transplants possibilities. Starzl’s protocol

was continued to use as standard for almost two decades.

(Barker and Markmann 2013) Following 1964 and up to 1980 there were no major revolutionary discoveries in the world of transplantation.

It was a period of constant innovation and improvement.

In 1984, on the other hand, being now transplants quite common, the US congress passed a law banning organ sale, and creating a centralized registry for organ matching. In 2005, following a study by Johns Hopkins University developed a way to have a donor ‘pool’ where donors, who couldn't, due to genetical incompatibility donate to their loved ones

would donate to someone else who in return would donate to whoever they wanted to save. This is a very important development in particular when talking about the future and possibilities in the future since, already, we are seeing how, thanks to this method, more people are being saved without any side effects if not the organisation of this pool.

In future, this could be maximized and together with other technologies may bring a lot of innovation in terms of organ availability, now a major problem in most countries. (history.com 2018)

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Image of the first successful heart transplant, the operation lasted 23 hours, the difficulty and strain of it are shown in the right of the image where a woman that helped with the procedure is falling asleep on the floor

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Organ Banking and the Future of Organ Preservation

Diagram from Science Direct

An organ bank is the utopia in organ transplantation. It consists in the finding of a method to preserve organs for a long period of time, and ideally, for whenever they are needed. Nowadays, even if machine perfusion is very useful in preservation of organs, it only does this for a couple of days, it therefore facilitates transport and gives more time for both the organ and patient to reach the place where the transplant can be carried out. It doesn’t however give the possibility for the organ to wait for the p a t i e n t , i t ’s a l w a y s t h e

inverse. (de Vries et al.

4/6/19) For this reason, in Italy, in 2020 more than 6000 people were on a waiting list for a kidney transplant. In 2019, 171 people died while on the waiting list for a kidney transplant (Conor, Mar 29, 2021). While kidney transplantation is the most negative data, being the need for the transplant the most common, the data shows how inefficiently organs are used and it’s for this inefficiency that a waiting list is needed.

With the existence of an organ bank, it would be the organs, which would be

stored until someone needs one of the organs. This would take away the waiting list but rather create a situation of practically immediate organ availability. Ways to prolong over machine perfusion times the lasting of an organ before implantation are through High subzero techniques, including supercooling or partial freezing which would preserve the organs up to weeks, or through Cryo methods, such as slow freezing or vitrification which could preserve organs for up to years.

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Machine Perfusion Machine perfusion is a way to preserve organs for days as well as it being an efficient way to check if they are idoneous for transplantation. The way it works is the following; the organ is attached to a machine that, like an artificial heart pumps blood, or depending on the case other perfusates, through, so the organ can work as if in the body, it could be considered as a small artificial body in which the organ is placed to be kept alive. There are three types of machine perfusion, normothermic, subnormothermic and hypothermic. In this brief explanation we will focus on normothermic MP (short for machine perfusion) and hypothermic MP since they are the most used and have very different functions, while sub normothermic MP is less common and more in the middle of the two. The Normothermic MP is mostly used in liver transplantation, and while it sometimes gets used also in kidney or lung transplantation we will focus on the liver to better understand it’s functioning. Since we will later discover that hypothermic perfusion gives the possibility for a greater storage time, normothermic perfusion is now used for another function, where hypothermic machine perfusion isn’t as

effective. In fact, instead of allowing for longer organ preservation, normothermic mp is used to control the organ’s efficiency and suitability for transplantation before it is physically placed inside the body, this is done by permitting it to, and controlling metabolic reactions and other parameters in the liver. According to dr.Watson, 10% of activity he

Hypothermic perfusion is perfusion, therefore the pumping of a solution through the body between temperatures of 1 and 10 degrees celsius. While this allows for some more preservation time the main benefit is the better results post transplantation due to better organ functioning. This is due to better preservation before transplantation.

and his team carried out in 2015 used livers which otherwise wouldn't have been used (Watson 2018). This technique, while less efficient in storage time has found another use, the controlling of organs, allowing for organs which would fail after the first year or so to be prevented from being transplanted and for organs which due to uncertainty would have been discussed to have the possibility to be used.

Hypothermic MP however has a different effect and therefore

Diagram from Yuri Boteon

Diagram showing procedures before transplantation

a different usage. In fact instead of checking suitability for transplantation it is used to increase preservation time or to reduce risk of malfunctioning post transplantations, like non anastomotic biliary strictures (van Rijn et al. 2021).

Diagram fromPlos One

Diagram showing machine perfusion functioning

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High Subzero High subzero techniques are supercooling and partial freezing. They allow for an organ to be preserved for either days or weeks.

Supercooling is a process done by utilizing antifreeze chemicals that allow then for storage at subzero temperatures. Subzero temperatures, unlike higher temperatures allow for the metabolic reactions inside cells to slow down significantly. While tests have proven to conserve damaged organs for up to 27 hours, some doctors such as dr. Uygun, say that, while having no test, they don’t know exactly how many, but the supercooling technique could preserve an organ for days. Partial freezing on the other hand is freezing at high subzero temperatures, avoiding ice crystal formation thanks both to the relatively high freezing temperature

Photo by KORKUT UYGUN/ MASSACHUSETTS GENERAL HOSPITAL

and partly by using biocompatible ice nucleators, agents some animals use when freezing their cells so they don’t get damaged.

While this is still a hypothesis, it is predicted it could extend duration from 2 weeks up to 49 days (Taylor et al.).

C r y o Preservation

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Vitrification and slow freezing are cryo methods of organ preservation and are what would allow for effective organ banking. The reason organs can’t simply be frozen normally is that the formation of ice crystals inside the tissue causes the tissue to rupture and the organ, once de-frozen, can't work. While antifreeze chemicals can work on smaller scales, such as singular cells, they can’t

work on an organ, this is because the organ is bigger and has many more points where crystal forms that aren’t protected by antifreeze drugs. The process of vitrification tackles this problem by freezing the organ is a specific way, and using specific chemicals that prevent ice crystals from forming (Cossins 2014), substantially turning the organ in a glass like form, (Scudellari, 2017) however the amounts needed of some chemicals are sometimes toxic to human tissue, factor limiting the use of these chemicals or natural cryoprotectants, such a glycerol. This was carried out on a rabbit kidney, where it was frozen at -122 degrees celsius and kept frozen for ten minutes before de freezing it and transplanting it in a rabbit, that lived for 48 days before it was killed for examination.

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This was proof that vitrification could work.

However, due to a part of the organ being hard to reach with antifreeze drugs it was a little bit ruined, making the organ less performant than a normal one. Another problem is the risk of the glass like structure cracking if heated unevenly or too fast since formation of crystals when the organ is heated is a greater risk than during freezing (Scudellari, 2017).

Another cryo possibility, that could allow for very long organ storage time, and possibly open the way for organ banks together with vitrification is slow freezing.

Slow freezing is the process of freezing liquids into solids slowly to prevent the formation of ice crystals since it gives time for the water to exit the cell, if this process is done too slowly however the organ is exposed to other types of

cryodamage. Similarly to vitrification one of the main problems in this method of cryopreservation is that an amount of cryoprotective agents that would totally protect the organ would become toxic to it. (bojic S. et al. 2021)

Conclusion In conclusion, I believe that, as time goes on, continuous progress is made towards the development of new organ preservation technologies. This is done so that, possibly, one day, these can be used to create organ banks and it can start being the organs that wait for someone in need of a transplant rather than someone in need having to wait for an organ, time that may even be anticipated by his death. While this still remains a remote idea, far

from being possible, important steps are being made towards it and it something very important to know about when considering a career in surgery or even more if considering to work in the transplant sector.

Photo from Science Photo Library

Conceptual image regarding organ banking and engineering

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An Expert’s Insight Interview with Dr. Barbara Antonelli Liver Transplant Surgeon at Policlinico di Milano Is machine perfusion used at the polyclinic? since when?

Organ perfusion techniques in transplantation activities are divided into three categories: - DCD (Donation after Cardiac Death) donors, - DBD (Donation after Brain Death) donors during ECMO (Extracorporeal Membrane Oxygenation) treatment -ex situ perfusion.

More frequently, the term "Machine perfusion" is used to identify ex-situ perfusion, that is, after having removed the organ.

We introduced this technique in the Polyclinic in 2017 and use the "Liver Assist" system, supplied in Italy by the Avionord company.

We use it in case of: -DCD, - the need to prolong cold ischemia (if a time of more than 12 hours is expected from collection to transplant), - for the evaluation of the organs considered "marginal" (with characteristics that can make functional recovery problematic).

In which cases and how commonly is it used?

The use of MP makes it possible: - the use of DCDs in Italy, where our legislation provides for a much longer time than in other countries for the declaration of death which would make these organs difficult to use, - the use of livers that would not resume function because they have suffered too long ischemia, - the evaluation of organs that would be discarded for too high a risk of non-functional recovery.

How has machine perfusion changed / is changing the world of liver transplants?

Experimental research is in continuous development, and everything currently aims at optimizing organ conservation.

Are there other technological innovations in transplants that could change the surgeon's experience in this world over the next 5 years?

All our work is aimed at improving the survival results of the graft (transplanted organ) and the patient; not so much to our quality of life, unfortunately!

Undoubtedly, compared to the past, the current management of donor intensive care and organ conservation techniques allow for a slightly more relaxed organization of harvesting and transplant operations.

For example, if twenty years ago, when a donor was reported, people left immediately for the removal and the transplant was often done at night, today it is possible to take at night and be a recipient during the day.

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Do you think that the introduction of technological innovations in the world of transplants could change something from the point of view of the surgeon's life and working hours? And is there investment on new technologies?

The world of transplantation is an extremely expensive field and fortunately our health system guarantees its existence, also investing in every available technological innovation.

The big problem that makes this work in Italy unattractive is that much less attention is given to the staff who are dedicated to it, from researchers to clinicians.

What do you think of the idea, although still remote, of organ banking?

Organ banking would be a dream, above all because it would mean having access to organs in times of need and would allow a transplant system in "election" that is, organized and not in "urgency" as we work today.

Today the number of recipients is much higher than the number of available donors, so I fear it is very complicated to do so.

Last but not least, it is essential that the transplant remains free from any risk of profit and accessible to those who need it, not to those who can afford it.

Regarding surgery, do you have any colleagues who use, or have you ever used, the da vinci robot? If so, what impact do you think its use may have on surgery?

I am the head of the hepatic robotic surgery project at the Milan Polyclinic and at the moment the only one to perform it as the first operator.

The Da Vinci has the enormous advantage of overcoming the limits of laparoscopic surgery (minimally invasive with "rigid" instruments) and of getting very close to laparotomy (or "open" surgery with a classic cut).

The instruments are equipped with a "wrist" that imitates the movements of the hand and is truly exceptional allowing you to make gestures that otherwise would be possible only with an open abdomen.

The advantages of a minimally invasive surgery, when possible, are above all linked to a faster recovery, less pain and, last but not least, a better aesthetic result.

In my world, hepatobiliopancreatic surgery cannot be used for every surgery, but we are using it more and more often.

Do you recommend particular paths regarding the studies to be undertaken in order to be better prepared for the surgery of the future?

The Surgery of the future, obviously leaving out the degree in Medicine and Surgery and the subsequent Specialization School, today cannot do without Engineers and Biotechnologists.

Photo by luckystep48

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Transfusion Medicine and Hemotherapy, vol. 46, no. 3, 2019, pp. 197–215, 10.1159/000499453. accessed november 2021. van Rijn, Rianne, et al. “Hypothermic Machine Perfusion in Liver Transplantation — a Randomized Trial.” New England Journal of Medicine, vol. 384, no. 15, 15 Apr. 2021, pp. 1391– 1401, 10.1056/nejmoa2031532. accessed november 2021.