Original articles Surg Endosc (2002) 16: 1403±1408 DOI: 10.1007/s00464-002-8587-2 Ó Springer-Verlag New York Inc. 2002
Disruptive visions Moral and ethical challenges from advanced technology and issues for the new generation of surgeons R. M. Satava Yale University School of Medicine, Department of Surgery, 40 Temple Street, Suite 3A, New Haven, CT 06510, USA Received: 10 May 2002/Accepted in ®nal form: 14 May 2002/Online publication: 12 August 2002
Abstract Numerous advanced technologies, both medical and nonmedical, are emerging faster than their social, behavioral, political, moral, and ethical implications can be understood. Some of these technologies will fundamentally challenge the practice of surgery: human cloning, genetic engineering, tissue engineering, intelligent robotics, nanotechnology, suspended animation, regeneration, and species prolongation. Because of the rapidity of change, the current status of these emerging technologies with their speci®c moral and ethical issues must be addressed at this time by the new generation of surgeons, or we must all face the consequences of an uncontrolled and unprepared future. Key words: Technology Ð Morality and ethics
There is no questioning the incredible introduction of new technologies throughout the 20-th century. In centuries past, technology had appeared in a slow and measured fashion, with a predictable linearity. However, the recent trend of technology introduction has been following an exponential growth, as most clearly illustrated by the information technologies of computers, communications, and the Internet. There are numerous other technologies which are also emerging with the same or greater rapidity and which will have as much or greater eect. Although the focus here is upon the technologies, the accelerated growth is fueled by a concomitant revolution in technology transfer, manufacturing, distribution, and commercialization. At no time in history have new ideas or inventions been brought to product so quickly or distributed so widely. Thus, the impact of any disruptive technology is immediately felt on a global level [3]. Unfortunately, our political, social, and behavioral response systems are too slow to respond and the moral and ethical implications are either ignored
or subservient to a more pressing (commercial?) need. Although nontechnology issues are dicult or nearly impossible to address in a scienti®c manner, a discussion is warranted in order to emphasize the urgency of issues. Some of the more important and obvious emerging technologies are human cloning, tissue engineering, genetic engineering, species prolongation (longevity), suspended animation, virtual humans (holomers), intelligent machines, nanotechnology, and surgery in space. Each of these will have enormous impact and create major shifts in the future of medicine, yet little attention has been paid to them by the medical community at large. Like so many innovations in the past, such as laparoscopic surgery or the sequencing of the human genome, the revolution is upon us before the more important moral and ethical issues can be addressed, such as training surgeons appropriately [11], ecacy of procedures, and the environmental impact of genetically engineered foods and prolonged lifespan. Although all of the implications of the new technologies cannot be foreseen at this time, it is critical to identify the likely candidates which have the potential to disrupt our conventional thinking about medical care and investigate their social, behavioral, political, moral, and ethical implications. Many critics would argue that some of the technologies cannot be realized in the next two to three decades, yet the issues are so profound that even longer time spans may be inadequate to prepare for the consequences. There are numerous implications and consequences of advanced technologies; the following examples address some of the known issues. These issues fall into several categories: scienti®c (is the science really safe?), social (what are the societal implications?), behavioral (how will individuals' behavior change?), political (how will the legal and regulatory systems react?), and philosophical (what fundamental moral and ethical precepts are challenged?).
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The technologies Human cloning Ever since the announcement of the successful cloning of Dolly the sheep [18], the specter of human cloning has been raised. The immediate response of a call for caution from the scienti®c community was positive, and the political will was engaged, resulting in a consensus that human cloning shall not proceed until adequate scienti®c evidence can be acquired and the moral and ethical issues addressed. Unfortunately, the global will of caution, signed by nearly every nation, is about to be ignored. At least two highly quali®ed groups have been established in oshore countries which are not signatory to the global accord. Recently there has been the announcement of the cloning of a human embryo by a private, commercial company which is not legally bound by the passed legislation. There has also been an announcement (though not independently veri®ed) that one woman is currently pregnant with a human clone [2]. Initially, the science of human cloning will only be available to stable married couples who have been unsuccessful in every known means of conception and fertilization and still choose to have their own child instead of adoption. Although this may sound like a noble goal, the lines will blur, or others will choose to aord cloning to nearly anyone for moral or commercial interest. Since the science is not yet perfected, it is inevitable that some disastrous mutations which do not spontaneously abort will be created; who will be responsible for caring for these individuals? Socially, will a new ``class'' of people be evolving? Will people react (behavior) to the clones with fear and resentment? Politically, who decides the right to be cloned Ð is it an individual decision? And will the clones have the same rights as naturally born individuals? Morally, is it right to create new life? Should we clone armies or breed special types of individuals, as in Brave New World? Regrettably, the world will be continuing to debate these issues without resolution while the ®rst human clones are born. Hence the urgent need to consider the following technologies, which will have lesser or greater impact, before they come to clinical practice. Genetic engineering The history of genetic engineering is well established. There are laboratory animals, such as knockout mice, which have been speci®cally ``designed'' with the absence of certain genes in order to accurately study human biology, physiology, and disease, and this technology is extending further to more precise methods of design [4]. Certain livestock, such as cattle and goats, has been engineered to produce coagulation factors, ®brinogen, or spider silk proteins [10]. Many of the forthcoming innovations will be implemented through genetic manipulation of stem cells. A few of the discoveries have begun translation into clinical practice with obvious success, such as replacing genes in individuals who lack a certain critical gene (e.g., von Wille-
brand's disease). Although the initial successes do not appear to pose signi®cant problems, more adventurous genetic engineering certainly will. An example of the complicated nature of the issues is the legislation against embryonic or fetal stem cell research. Laws have been enacted to prevent research on human fetal stem cells until evidence becomes available about the possible negative eects as well as the harvesting of the stem cells; in the meantime, the potential for modi®cation of these cells to provide a cure for paraplegics from spinal cord damage is being delayed inde®nitely during deliberations. What are the implications of ``designing'' children, and what are the consequences if the parents do not get the trait they expected? Are we on the path to eugenics? Even worse, what happens if an error occurs, resulting in a congenital anomaly with disability, dis®guration, or abnormal behavior? Will there be fads for certain socially desired characteristics, or could the genetic alteration enhance certain properties such as mental or physical abilities? Who decides what engineering occurs Ð the parents? What are the problems associated with designing children with advantageous characteristics? Will only a select few auent families be able to aord this advantage, and will it propagate an ``elite'' class of people or leaders? Tissue engineering, regeneration, and intelligent prostheses The state of the art in tissue engineering is limited to tissues with a few layers, such as bioarti®cial skin or blood vessel segments. However, rapid progress is being made in growing bioarti®cial organs with full, three-dimensional architecture [9]. This is accomplished with bioresorbable scaolding of vascular tissue, which will then be seeded (in bioreactors) with stem cells from appropriate organs or tissues, such as kidney or liver. Currently clinical trials are ongoing for bioarti®cial heart valves, cartilage, and bone. It is anticipated that within the decade, bioarti®cial organs will be available for transplantation, generated from the patient's own stem cells, thereby eliminating the problem of rejection as well as the current scarcity of donor organs. Other research in tissue regeneration has had limited success in the areas of regenerating nerve cells [7], with success in invertebrate models of other tissues. The anticipated long-term goal is regeneration of body organs, limbs, etc. And ®nally, prostheses (which started with the humble limb or hip prostheses or cardiac pacemaker) are becoming intelligent with embedded microsensors and are custom manufactured for individuals, providing capabilities beyond those of natural systems. Some prostheses are being controlled by direct connection to the brain, as in the experiments with monkey brain implants controlling a remote robotic arm [16]. Although tissue engineering may be a welcome solution for the organ transplantation crisis, will this spill over to wholesale organ replacement? Will surgeons of the future simply replace a diseased, malformed, or cancerous organ with a ``new'' one? Through the growth
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of organs/tissues, or genetic engineering of tissues, or manufacturing of prostheses, will it be possible to provide ``suprahuman'' capabilities, such as the ability to see in the infrared or ultraviolet portion of the spectrum (as many birds and animals do) or to see in the dark using implanted ultrasound sensors, or the development of extraordinary strength from muscles enhanced with electroactive polymers? Considerable research is being devoted to neural (brain) implants or direct brain±machine interfaces; what are the implications and complications of directly communicating with computers, connecting to the Internet, or perhaps direct brain-to-brain interaction? Who will pay for the expensive bioreactors to grow and tissue banks to store the organs? Will persons who receive supranormal sensory organs (eyes, ears, muscles) be treated as anomalies or freaks? Politically, will there be a new class of people who can aord the technology, who will therefore live longer and perhaps be politically more powerful? And ®nally, what will it mean to be ``human'' if nearly all of your body is replacement parts or if you do not ``look'' human?
normal behavior [13]. Although this experiment is admittedly for a short period of time, the question does arise as to what bene®ts would accrue from either shortor long-term successes. Scienti®cally, short term (a few hours) may provide a substitute for anesthesia or cardiopulmonary bypass during surgery, or during emergency treatment in exsanguinating hemorrhage or cardiac arrest in the pre-hospital (or battle®eld) setting. However, since the experiments have only been conducted on dogs, we do not know the immediate or longterm eects on humans. Socially speaking, will the science be accelerated to a point where humans can hibernate for years, and if so, how will these people cope when reawakened? Or perhaps is science ®ction correct: Is this the only way to explore the solar system and beyond? Politically, if persons are reawakened years later will there be con¯ict with past and future cultures? Morally, will we need to suspend everyone with an ``incurable disease'' until the cure is found? Will no one be allowed to die, but rather will the dying be put into suspended animation? Who chooses which person receives the treatment?
Species prolongation (longevity)
Intelligent machines (robots, computers, etc)
The average lifespan of humans in the advanced nations has slowly been increasing, with the average in the United States now being greater than 75 years. However, no human has been documented to live longer than 123 years Ð the total possible lifespan has not increased. Recent experiments in the area of apoptosis, telomerase, and genetic engineering have resulted in animal subjects with one and one-half to two times normal lifespan [14]. Will this be possible in humans, or will this result in unforeseen mutations and abnormalities? What are the consequences of people living 200 years? Socially, will there be a new ``class'' of long-lived people? And will they be resented? Since there are grave concerns about overpopulation, what bene®t is there to exceptionally long life? Will multiple careers become necessary? Politically, older, more experienced people tend to want to keep the status quo Ð will there be a slowing of progress? Morally, is there really a need to live longer? Will this result in even more of the depression, anxiety, and mental illness than we already see in the elderly?
The human brain has been estimated to perform or ``calculate'' at approximately 4 ´ 1019 computations per second. The current most powerful computer, ASIC Red at Los Alamos Laboratory, will perform at 30 tera¯ops (3 ´ 1016 computations) per second. It is anticipated that Moore's law (liberally interpreted as ``computational power doubles every 18 months'') will continue to apply, and therefore in the next 20±30 years, there will computers (or some machine) that will have computational power that is the same as or greater than that of the human brain. Software programs are becoming so complex that new programming is being written so computers can generate their own programs, as well as debug them. Should these trends continue, will the machines, computers, or robots become ``intelligent''? What will it mean to be intelligent? Will humans be able to communicate with them? What will the bene®t to society beÐto replace all mundane work with robots, leaving only leisure, art, etc, for humans? Will there be resentment against the machines? Will there be political movements to provide ``rights'' for intelligent machines? Will such machines even need humans, whom they might consider inferior? Morally, will we be able to disconnect or ``kill'' a machine that is intelligent? Will we have to rede®ne what it means to be human? Eventually, we may have to face the question of whether we could ``download'' our intelligence our ``selves''? into a machine or robot.
Suspended animation The desire for suspended animation has been relegated to the areas of speculation and pseudo-science, with commercial ``cryogenics'' being oered for persons with incurable diseases to be in hibernation until a cure can be found. Until recently, there has been no veri®able scienti®c evidence that such procedures are valid. However, there has been modest success recently in controlling cellular metabolism. Dogs have been made asystolic, given an intravenous solution to slow cellular metabolism along with mild hypothermia, and then resuscitated 20 minutes later and have demonstrated
Holographic medical electronic representation (Holomer) The holographic medical electronic representation is both a medical record and a method of interacting with information (a computer±human interface). The holo-
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mer has been implemented in experimental studies [15] and is based upon the current technology of total body scanning, which gives an accurate image of the individual. It is an avatar, a human surrogate in cyberspace, an electronic computer representation of a person based upon patient-speci®c data from historical, genetic, molecular, biochemical, physiological, and digital imaging sources. The database can be stored on a computer, on an Internet Web page, or on a credit-card-sized medical record. This record can be viewed upon a computer; however, what the patient or physician sees is a threedimensional exact duplicate of the patient. Abnormal data (lab values, x-ray ®ndings, etc.) can be automatically highlighted, calling attention to speci®c problems or abnormal values. The image can be queried simply by clicking on the appropriate organ, such clicking on the pancreas for the insulin or blood sugar levels. The entire body can be made transparent to view speci®c organs, and the organs can be ``¯own through,'' as in virtual colonoscopy [17], for noninvasive diagnosis. Archived data can use intelligent algorithms to compare sequential sets of data for outcomes analysis and simulate possibility of future disease. And the list of emerging applications and potential capabilities goes on. Can the holomer actually be used to ``predict'' the health future of an individual, even if bad? Will one company gain a monopoly on the data (a healthcare equivalent of Microsoft)? Can someone manipulate your dataset to result in physical harm? What protection of the data is needed to provide security of the holomer from abuse or discrimination, such as by government regulators, employers, or insurance companies? The behavioral consequences of too intense of an identi®cation with a person's own avatar can be extrapolated from studies with playing games, which have documented that a number of children actually identify with their ``characters'' and suer actual physical reactions (depression and even suicide) when something occurs to their avatar [1]. Will a person's life be regulated by the information in his or her holomer? Will these human surrogates be let loose on the Internet and actually gain political power for their human counterparts? Should the government have speci®c ``rights'' over your holomer? Are there moral or ethical implications of simulating your life, and then modifying your life based upon these simulations? Nanotechnology Nanotechnology is the world of the smallÐthe world of individual atoms and molecules. Introduced ®rst in 1959 by Richard Feynman [6] and championed in the 1980s and 1990s by Eric Drexler [5], nanotechnology is now a serious science. The promise of nanotechnology is that it is possible to create literally anything we choose simply by constructing it atom by atom. The ®rst success was carbon±carbon nanotubulesÐa material that is 10 times as strong and one-seventh the weight of titanium, the strongest known natural material [8]. In addition, because these creations are at the molecular level, new approaches to building computers on the nanoscale
(1000 times smaller than those that are available today) will result in both more powerful and smaller computers, to a point where they will be so small that they can be implanted anywhere. Today, small nanomotors are being constructed, 100 times smaller than a red blood cell. Future applications (many decades) could include nanomachines that are injected into the blood stream; however, near-term construction will result in simple, ``intelligent'' drug delivery systems that seek out speci®c targets, such as cancer or islet cells. Although some of the nanosystems will be manufactured, many will need to be created by self-assembly, analogous to the manner in which the human body ``self-assembles''. The scienti®c challenge will be to control these processes and to be certain that mutations do not occur, especially ones that would promote cancer, autoimmune disease, or other unintended consequences. Will such systems eventually replace surgeons, when machines can simply be sent inside the vascular system to ablate or repair damage? As in tissue and genetic engineering, will some people be given enhanced capabilities, longevity, or other attributes? The same questions about overpopulation, living too long, who decides on who receives the bene®ts, and resentment between haves and have-nots will apply. Current work on nano tags (which can be inserted in the body for identi®cation, etc.) provokes memories of Big Brother and other privacy issues. Morally, should we implant these identi®cation tags into criminals or other people to track them, especially against their will?
Microgravity medicine The International Space Station (ISS) is a reality, with crews working in space on 3-6-month rotations. Soon these work rotations will become longer, requiring prolonged habitation in the zero-gravity environment. To date, there are at least eight areas of problems with prolonged exposure to microgravity (lG), including calcium/bone loss, muscular deterioration, and cardiovascular deconditioning [12]. On the other hand, these same deleterious eects may actually be bene®cial to persons with certain disabilities (e.g., paraplegics or those with congestive heart failure). Humans have not shown the capacity to completely adapt to these changes within a year of space accommodation, so will there be mutations as a result of either prolonged living at lG or being born in space? Will humans become lG-tolerant, only to lose the ability to survive on Earth if they spend most of their life in space? Will it be necessary to develop entirely new behavior and methods for living, especially when space travel becomes commonplace? Politically, will inhabitants of space eventually declare themselves independent, and will they be resented? Would it be ethical to genetically engineer a person to be tolerant to lG, especially if that person would not be able to return to Earth? What preparations have surgeons made to address the unique challenges of lG when the time to perform surgery in space is a reality?
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The moral and ethical issues The preceding review of advanced technologies that are currently emerging from the laboratories is neither comprehensive nor entirely representative. The examples meant to raise the reader's awareness of nontechnical issues which the accelerated pace of innovation is forcing upon us. There are a number of these issues which the current generation of surgical residents must addressÐscience waits for no one. Let the current unprepared response to human cloning, with all its profound implications, serve as a warning and wake-up call. Here are a few of the issues that will likely need to be confronted by our new generation of surgeons during the 20±30 years of their professional careers. What does it mean to be human? As the various technologies, such as genetic and tissue engineering, intelligent and neural prostheses, humanlike machines/robots, and regeneration, replace more and more of our natural biological bodies, exactly what will be the de®ning characteristics of a human? How long should a person live, and do people have the right (obligation?) to die? With the advances in understanding the proteins, structures, and cellular functions involved in cell death and aging, humans will have the opportunity to actually live longer lifespan. Perhaps the children of the next generation of surgeons will have a life expectancy of 200 years or longer. How do humans cope with this extended lifespan, how do we determine when a person is dying, and should there even be a consideration of a right, let alone an obligation, to die? How do we implement suspended animation (controlled cellular metabolism)? Success in sustaining vital cellular functions at a remarkably reduced rate of physiologic activity (e.g., asystole or extreme bradycardia) begs the question of whether this can be a revolutionary replacement for anesthesia, and whether it will be possible to extend such a state beyond minutes or hours to years. Can it be possible, and is it practical or ethical, to suspend terminally ill patients for years in hope of a cure to their disease? What are the incredible social, ®nancial, political, and other implications of reawakening decades in the future with little if any biological increase in age? How will humans interact with intelligent machines (computers, robots, etc.)? Although it is not certain, there is high likelihood that the next two to three decades will see computers or robotics with capabilities vastly superior to those of humans, not only in a single area but in a large array of
human activities. In addition, research in neural and brain prostheses and interfaces points to the possibility of direct connection to the brain, initially in some minor way. Will our children rebel by ``plugging in'' to the Internet or each other, as rebelling children today are fascinated with body piercing? Will these machines be ``intelligent''? How will humans control them? Will we interact with them in a form of human±machine direct interface? As we understand and program more and more emotion into the machines, will they assume humanlike characteristics? Over a greater time, will the machines even need us any more? What is the consequence of an information equivalent of yourself (holomer)? In the near term, the holomer will emerge as a data repository and an intuitive method of interacting with massive amounts of data, but the holomer can also be an individual surrogate on the Internet. Will there be regulation of this alter ego? Will a time come when persons cannot distinguish between their physical selves and their information selves, What are the consequences for the mental health of such individuals? As we become more involved with our personal holomer, as more data makes the information equivalent a closer representation of our actual self, and as technology (such as neural implants and direct brain±computer interfaces) matures, will we actually ``download'' ourselves into the Internet? Should our representation in information space replicate ourselves, or should we ``design'' our representations? Will some persons become so powerful in cyberspace that they will neglect their physical bodies? What is the direction of nanotechnology? Will microscopic ``machines'' be inserted into the vascular systems to deliver drugs or perform surgery? As we embark on creating new materials, objects, machines, and perhaps life forms by initiating their assembly atom by atom, will we be able to control the results of this self-assembly process? Will we create materials that cannot be destroyed or recycled? Will new areas of medicine and surgery open in the space environment? Research in the area of the known problems of lG has not provided counter measures. Very little research has been done on surgery in the lG environment. Are surgeons prepared to enter this harsh and unforgiving environment? Will there need to be separate societies for space surgeons, with special training in multidisciplinary ®elds? There are certainly many other vital questions with only relative (not absolute) solutions that must be considered. The above are oered as a starting point, rather than a list of the most critical issues.
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Conclusions Whenever there is a revolutionary technology that radically disrupts the current status quo of surgery, such as endovascular or laparoscopic surgery, we can look back (with a ``retrospectoscope'') and trace the scienti®c origins; however, the problems engendered by the disruption (e.g., more common duct injuries from laparoscopic surgery, loss of surgical cases from vascular surgeons to interventional radiologists) overcome our ability to rapidly respond to the technology. We are always reacting in a crisis mode, rather than proactively considering the alternatives in a calm and measured light. Admittedly, some of the technologies, such as suspended animation and intelligent machines, have been the stock of science ®ction for decades; however, so was human cloning, instant global communication, and space travel, and we were clearly not prepared to face their consequences. As little as 50 years ago, a person would have been considered totally insane to say that a human would walk on the moon (jet planes were just becoming commonplace; no rocket had ever been launched into space). But Sputnik in 1957 gave serious pause to scientists and to society, and the ®rst footstep on the moon on July 19, 1969 (only 12 years later!) would have proved that person to be a visionary. This manuscript is an attempt to be proactive (and provocative), to look at some promising and likely emerging technologies decades (and the time frame of decades must be emphasized) before their profound eects, and to begin to address the obvious nontechnical con¯icts, especially moral and ethical, which they will create. There is no question but that humans will need to face the issues listed above (and probably many others); the only real questions are when (most of today's residents will be confronted during their surgical career) and will we be prepared? As the famous science ®ction ®lm director Steven Spielberg has said: ``There is no such thing as science ®ction, only scienti®c eventuality.'' I concur with this opinion in regard to the technologies addressed above: The emergence of the fundamental science and technologies to generate these changes, coupled with the current exponential growth of technological innovation, makes their eventual reality inevitable. In the context of speculation, consider the following rhetorical statement, compared to its profound implication: ``The human species may be on the brink of a revolution that is even greater than ®re or the wheel: Humans are the only species with the capacity to direct its own evolution (genetic engineering, cloning, etc.) at humans' own accelerated paceÐno longer by the will of Nature nor the excruciating slow pace of evolution.'' This may be the ultimate challenge for the next generation of surgeons (and humans). It is also critical to realize that technology has no moral value: It is neither good nor evil. Rather, it is the
application of the technologies which raises the moral and ethical issues. These issues must begin to be addressed in annual scienti®c conferences, and a sense of vital principles must be integrated into our residency training programs. Surgeons and physicians, as pillars of moral conscience, have recently been forgetting their Hippocratic Oaths and stewardship to society, and have been languishing in the short-term gain of ®nancial security and self-centered comfort and leisure. As scientists and humanists, surgeons must be aware of their responsibility in this awesome challenge and accept a leadership role through the coming decades of nearly impossible decisions.
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