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The role of technology in vascular surgery
THE ROLEOF TECHNOLOGY IN VASCULARSURGERY D. E. Strandness,
Jr.
ABSTRACT
opening
This paper is based upon a plenary
lecture presented
at the
London
of the International in September 1981.
Vascular Symposium
held in
Keywords: Surgery, technology, vascular surgery, clinical research
While it would be possible to simply catalogue the technological achievements in vascular surgery, a much broader view concerns not just technology but the place of science in this field. Advances in vascular surgery are dependent upon new and better science which can only occur with the development of new technologies. This of course, requires people with vision and ideas who are encouraged to function in an environment dedicated to change. My own views expressed here are strengthened by references to colleagues past and present who have been instrumental in moulding my thinking. Many of us have, by force of habit, come to use words in ways that often tend to fit our own biases rather than reflect their true meaning. Technology is certainly one of these words. As derived from the Greek, it consists of two parts - techne, an art or craft or technique, and logos, which simply means a systematic treatment of the problem at hand. Everyone should immediately recognize that the definition of technology fits the field of vascular surgery very well. For example, resection of an aortic aneurysm or placement of a femoro-popliteal by-pass graft requires the use of techniques to treat systematically the problem at hand. If we take the definition one step further, the user of the technique must in fact be a technician. Surgeons themselves would appear to agree with this since they commonly refer to their colleagues as either good or bad technicians according to their ability to get the job done. Physicians on the other hand use the term technician to refer to the surgeon who may operate well but is unable to think well. How often have you heard ‘he is only a technician’ implying that the brain and hands may be connected but little else. These are simple examples nology and its derivations responses depending upon case of vascular surgery, it properly applied. However,
of how the word techcan incite different one’s perspectives. In the is obviously good when we all accept that even
Department of Surgery RF-25, School of Medicine, University of Washington, Seattle, Washington 98195, USA.
a perfectly performed procedure is bad if done on the wrong patient. Thus, the use of technology is heavily dependent upon its intended use and proper application. For some reason which is difficult for me to understand, many people have come to equate technology only with devices - machines if you will. Furthermore, when used in this fashion, it is often in a very negative context, particularly when viewed in terms of its impact on society. For example, I was fortunate as a medical student to be present during one of the very first attempts at renal dialysis in Seattle which was made under the direction of Dr. Belding Scribner. The discussions which followed this truly chaotic event would have discouraged most men. Yet the idea that this was indeed feasible coupled with an available technology led to a truly great contribution. In the case of medicine, particularly as it applied to its practice, technology has come to play a prominent role in many aspects of our daily work. A glimpse of a modern operating theatre and intensive care unit is impressive, even to those of us who have closely watched the technological developments in the field over the past few decades. Yet in the minds of many, there is always a lingering doubt that these advances may in fact not be necessary if we would only pay more attention to the patient and less to the numbers. These issues have been addressed by two eminent vascular surgeons. Dr. Detakats wrote in an editorial’ in 1980, ‘Technology also breeds technocrats who in turn manage and profit by technology.’ He extols the virtue of simplicity and rightly fears the intrusion of technocrats into some areas which are best addressed by seasoned clinical judgement and not by expensive devices. This will not occur unless this control is relinquished by those of us who are closely involved. Likewise, Dr. Wylie in his presidential address to the Society for Vascular Surgery was particularly critical of the philosophy that noninvasive testing is an essential component in the evaluation of the patient with known or suspected vascular disease’.
@ 1982 Butterworth & Co. (Publishers) Ltd. 0141-5426/82/030179-06 SOS.00 J_ Biomed. Eng. 1982, Vol. 4, July
179
Role of technology
in vascular surgery: D.E. Strandness
Dr. Detakats and Dr. Wylie approach the issue of technology from slightly different directions but their conclusions are very much the same. - The present approach to most problems is good enough if we would only take time to relearn the teachings of the past. Use your own senses, they are more than adequate. - Unfortunately, this is obviously not true given the knowledge we have gained over the past few decades. While there is always a place for concern we need more and better technology, not less. Is there any reason to believe that vascular surgery should not continue to progress along with the rest of the scientific community? We must of course define how technology relates to science and what its role and impact might be. The essence of science is the statement of an hypothesis following which systematic observations are made to determine whether or not the hypothesis is consistent with the facts. Technology on the other hand is a means to a particular end and involves finding answers to questions such as “how much”. The emphasis of technology is on methods. For example, we may want to know the peak flow velocity in the internal carotid artery and develop a method of measuring it. Thus, science and technology need not go hand in hand and frequently don’t. However, technology is playing an increasingly important role in the process of scientific discovery which is that of defining and redefining the areas in which the key scientific questions can be asked. Today, science is very dependent upon technoIogy and not the other way around. If this is in fact true, what can we do to prepare ourselves for the future? If medicine is to remain alive as a discipline devoted to scientific inquiry, we must be willing to re-examine the past while always looking to the future. The history of the medical profession is a complex, interwoven series of technological and scientific advances fostered by the genius of single individuals. Great ideas in medicine, as in the arts, are rarely the result of the decisions or deliberations of a committee but of individuals who observed things other people missed and then asked the critical question, “why?” The giants of our profession who brought US to this day had the capacity to ask key questions and then attempt to answer them by the use of available technology. We can still benefit by examining the history of vascular surgery because each great contribution with few exceptions was inspired by the work, and most importantly by the ideas, which preceded it. Progress in medicine has always been unpredictable. There are often long, quiescent periods which are suddenly interrupted by times of great interest and activity. The onset of renewed activity is usually heralded by some fundamental breakthrough or advance in technology which has opened the door to those willing to look.
180 J. Biomed. Eng. 1982, VoL 4, July
In 1976 Comroe and Dripps3 investigated the top 10 advances in cardiovascular and pulmonary medicine over the past 30 years (Table 1). With the exception of the prevention of poliomyelitis, each of these are relevant to those of us who practice vascular surgery today. As each of these are examined, it must be clear that technology played a critical role in these advances. While there is no doubt that the ideas for these advances originated in well prepared and thoughtful minds, the necessary technology was either there in place or ripe for development. This has and will for the future remain the pattern for new advances in the diagnosis and treatment of cardiovascular disorders. Comroe and Dripps also attempted to profiIe the research, and in particular determine the goal, of those responsible for the scientific and technological breakthroughs. As noted in Table 2,62% of the research involved some element of basic investigation. At least 41% was not clinically oriented at the time the work was done. They were able to identify 529 essential or key articles that were responsible for the new change in direction. This would average only 19 publications per year over this time span. It would of course be nice if it were possible to preselect the successful scientist but of course this is not possible. We require bright people in large numbers because the process of scientific discovery is by its nature very inefficient. Thus most of us who work in new areas will be forced to contribute most heavily to the journal of negative results moving aside for those few who will ultimately pave the way toward major breakthroughs. Given these considerations, what are the prospects for the future? Unfortunately, they are of great concern. Wyngaarden in 1979 published an article entitled ‘The Clinical Investigator as an Endangered Species4 .’ The number of physicians involved in research declined from 46% to 20% in just nine years. The number of physicians seeking research training dramatically declined in six years, from 4600 to 1790 with 70% of the budgeted positions unfilled. As stated by Dr. Richard Ross ‘The shortage was one of applicants, not opportunities5 . These are frightening statistics if we believe the future is important. This decline in research is of major concern not just in the United States but appears to be worldwide. Furthermore, there is an interesting tendency even by some leaders in the field to ridicule the scientist and academic physician as one who really does very little that is useful. They are satisfied with the practice of vasTable I Top ten advances
in the past thirty
years3
Cardiac Surgery
Oral Diuretics
Vascular Surgery
Intensive Care Units
Drug Treatment Hypertension
Chemotherapy
Cardiac Resuscitation
Diagnostic Methods
Medical Treatment Myocardial Ischemia
Prevention of Poliomyelitis
Role of technology
Table 2 Profile of research which led to major advances3 Basic - Not ClinicallyOriented
36.8%
Basic - Clinically Oriented
24.9%
Not Basic
21.2%
Review and Synthesis
1.8%
Development
- Research
3.9%
Development
- Clinical
11.4%
cular surgery in 1981 and often extol present accomplishments as proof that this is indeed the case. One aspect of this problem was put in proper perspective by Dr. James Stanley in his presidential address to the Midwestern Vascular Society. He stated: ‘Decisions based continually on our own biases are unacceptable, especially if reasonable biomedical research would afford a more rational clinical practice6 .’ I believe what Dr. Stanley is asking for is more surgeons to become interested in science. The scientist surgeon was described by Dr. Henry Buchwald in 1981 in the following terms: ‘He asks why in addition to how. Though he seeks to be a master of his technical craft, he is not satisfied to perform without understanding. Rapidly, often with great disillusionment, he learns that the answers to the ‘whys’ are frequently based upon shaky foundations, little more than custom and faith. A codification of repetitive practice is not science.’ . . . ‘Today’s research needs intricate and sophisticated instrumentation for the testing of hypotheses’ .’ This is true since many, if not most, of the simple experiments have been done. How much biomedical research devoted to vascular disease is being done within the surgical community? The programs of our meetings reflect current activities throughout the world as well as any single barometer. The program of a recent meeting of the International Society of Surgery included 198 abstracts. There were 8 papers (4%) devoted to vascular disease with only one being of a truly experimental nature. At the last meeting of the vascular societies in America, there were four papers (two vascular, two cardiac) which could be classified as basic research. This represented 9% of the total program. The remaining contributions were clinical papers. These are disquieting statistics, and what has happened is already having a serious impact on the attitudes of young investigators. If societies continue to emphasize the purely clinical papers, then we are truly in a rut which is nothing more than a grave that is open at both ends. There is little doubt that the social and professional climate both inside and outside the academic community has profoundly affected the trends in both basic and clinical research. Early in my career, institutions could be divided into those that provided a research opportunity as a required part of clinical training, and to those interested in a rigid, lock-step approach to specialty training. This has all changed
in vascukar surgery: D.E. Strandness
now, and with few exceptions, clinical training is designed only to meet the requirements necessary for certification. If the emphasis is only on clinical training, then the future is bleak. Another area to examine which always reflects current attitudes and practices is the journals in which we present our work. Nearly all of us are guilty of liking to see our name in print. This insatiable appetite on the part of our profession has led to the widespread proliferation of publications which cross our desks every day. For those in academic life, it is the key to survival and promotion, but unfortunately acceptance for publication cannot always be equated with quality. I have been as guilty as anyone in this regard, but I am becoming increasingly concerned by what I read. Most papers would not meet the requirements of even an elementary course in statistical design. About 10 years ago I was counseled by a wellknown surgeon to send my best work to non-surgical journals. This advice was given for a variety of reasons. First, I would probably find out very quickly whether the work had any merit and second, I would receive back a critical and constructive review. I have heeded his advice to some degree, and I would concur with his conclusions. If you really want to find out how well your work has been done, I can provide a list of journals who will put your work to the acid test of careful scrutiny, and they are not by and large surgical journals. The picture which I have painted to this point is bleak indeed, and I will frankly admit that I am discouraged by what I see. There are however some hopeful signs on the horizon. I spend a considerable amount of my time travelling throughout the world. Every place I go I find young surgeons, physiologists, and engineers who are eagerly trying to find answers to old and new questions. The amazing thing is their willingness to spend extra time, often at low pay, beyond that required for clinical training to develop competence in areas not intimately related to their primary discipline. They sense, often better than I do, the need to be different, to try new approaches and to develop expertise in areas of research that will set them apart from their peers. E’urthermore, they are willing to sacrifice the only non-returnable commodity we all have - time - to prepare themselves for the future. If I had to describe their attitude in a single phrase it would be - a deep dissatisfaction with the present. If we ignore their needs and concerns, then there will be no future other than the same repetitious recountings of the present. In my view, the development of a scientific approach combined with the proper application of technology to research problems is the only hope for the future. Without acquiring competence in allied disciplines, vascular surgeons and vascular surgery will have a very limited future. Certainly we can continue to train people to operate and do it well, but if this is our only goal, the speciality will soon lose the vitality which is so essential for growth.
J. Biomed. Eng. 1982, VoL 4, July 181
Role
of technologyin
~osculor
surgery:
D.E.Strandness
hr attempting to approach new problems, the technology required to do so may be very complex and out of reach of the average academic surgeon unless he or she is willing to spend extra time to become competent in more than one area. We must also recognize that we are living in a time when collaborative research is essential for the solution to most of our problems. However, I firmly believe that collaborative research of the best kind requires a considerable understanding of the problems by all participants. It is not sufficient to do this type of research at a distance by using other people to simply fill in the gaps and plug the holes. Those surgeons preparing for the future will have to become increasingly familiar with new technologies if they want to make meaningful contributions, and unfortunately this takes time. Of course, we all must at some point decide where the future lies, and how we can best satisfy both our personal and professional goals. In the final analysis, the future always boils down to having ideas. This is as we must recognize the most difficult problem of all. Once the decision is made to pursue an academic career, what technologies might be essential in the development of an adequate background? The list of specifics is of course long, but there are general areas that are of obvious importance which are shown in Table 3. As you will note, those listed are in reality disciplines to which people may devote entire careers. Some of you may well say that surgeons have no business working in these areas, but you are wrong. It is possible for surgeons to work in these areas and become knowledgeable enough to stand toe to toe with their colleagues in finding answers to questions. If we adopt the the philosophy that surgeons must remain surgeons and not step outside their field, there will be no future except continued excellence in the operating theatre, and while this is vitally important, this is much too short sighted. The result will be less applied research in the field and a greater assumption of this responsibility by other disciplines. This clearly is what is happening in cardiac surgery even though surgeons were the pioneers in many aspects of the field and put it where it is today. Epidemiology and biostatistics are not only important but essential if we are to plan good clinical trials. Surgeons must come to grips with the fact that very little emphasis has been pIaced on this area by our specialty. Reports on the results of Table 3 Disciplines growth
utilizing
technologies
essential
for
Epidemiology and Biostatistics
Cell Biology
Bioen&eering
Thrombosis and Haemostasis
Physiology
Biomaterials
Computer Science
Pharmacology
182
J. Biomed. Eng. 1982, VoL 4, July
surgical therapy are with few exceptions a statistical disaster which we all must recognize. If trials are to be meaningful, they must be carefully designed at the start - not analysed after the fact. The technology which is available and used in these disciplines is not beyond our reach, and we must start learning it. What have the retrospective analyses so commonly used by surgeons done for us? They have resulted in chaos and confusion and lead to meaningless and conflicting conclusions. Bioengineering is of course engineering applied to biological problems. It has extended itself into nearly every area of medicine and is an ideal area for surgeons to become knowledgeable. My own case is one in point. I am not an engineer, but I am familiar enough with the field so I can converse in a fairly intelligent manner about problems of mutual interest. It took me three years after completion of my residency to feel comfortable in this relationship. During this period, I devoted 75% of my time in accomplishing this goal. The technological advances provided by bioengineers working in concert with clinicians have been phenomenal and have had an impact on nearly every aspect of our research and practice. Some of the developments, such as the Gruntzig balloon catheter, are already modifying our approach to selected patients with arterial occlusive disease. Other advances, such as in the area of ultrasonic imaging and analysis of flow patterns, are permitting for the first time methods of identifying and following patients with disease of the carotid bifurcation. We now have the tools available to evaluate the natural history of atherosclerosis in this area and answer some critically important questions which are continually before us. Expertise in the physiology of the circulation would seem to be essential for every surgeon who assumes the responsibility for the diagnosis and treatment of patients with vascular disease. This is a critically important area where each of us can continue to make meaningful observations. Yet much of the confusion with regard to vascular disease is due to a lack of appreciation of the known pathophysiological mechanisms. However, the techniques that are available to study the circulation have become increasingly complex and require considerable time to master. There are so many exciting areas in which to work, it is a shame that surgeons aren’t playing a more active role. A few examples come to mind which offer great challenges, yet if successful would contribute in a major way to our understanding of important problems. It is well recognized that atherosclerosis of the carotid artery tends to be confined to the carotid bulb with remarkable sparing of the internal carotid only a few centimeters away. Evidence is accumulating that the flow patterns that occur across this complex bifurcation may play a role in the pathogenesis of atherosclerosis. Up to the present time, this could be studied only in a model system, but we now have
Role of technology in vawuhs surgery: D.E. Strandness
the technology available flow patterns at discrete bifurcation in humans.
to describe in detail the points across the carotid
Another important area which is really untouched, relates to the physiology of the collateral circulation. These intriguing vessels, that are the surgeon’s best friends, are begging to be studied. Even today, our knowledge concerning the function of these vessels is virtually nil. In fact, we are forced to conclude, as John Hunter did, that “vessels go where they are needed.” The problem of unravelling why or how these bypassing conduits get their messages is not a trivial one but is certainly deserving of the attention of several lifetimes. Computers are here to stay, and we must more actively incorporate this technology into our efforts. Computer technology combined with statistical expertise provides us with very powerful tools. They can handle, store and retrieve immense amounts of data very quickly. For clinical trials, analysis of complex data and statistical analysis, they are absolutely essential. With the rapid progress in microelectronics, the versatility and memory capacity has increased dramatically, while there has been a decrease in price. It is now possible to obtain “small” computers (in physical terms) with capabilities unheard of even ten years ago. We must become familiar with these aids, since they will not only save us considerable time but will also make the whole area of data management in surgery available to us at relatively low cost. Cell biology is obviously a very broad field whose major focus is to describe changes at the cellular level to a variety of stimuli. For example, there is an extraordinary amount of work being done in the area of atherosclerosis as it relates to the response of both endothelial and smooth muscle cells to injury. A pressing problem is vascular surgery relates to the issue of graft failure and those factors which lead to the development of the commonly observed pannus at the distal anastomoses. A great deal of work needs to be done here to elucidate the causes for this problem and determine if we can modify or prevent this from occurring and prolong the life of an implanted graft. The field of thrombosis and haemostasis is of obvious importance and interest to the surgeon. One need only examine the problem of acute venous thrombosis to assess the impact of technology on interest in the field and the dramatic progress which can follow the introduction of a single observation. While deep venous thrombosis has always been considered a major medical problem and is constantly with us, interest and enthusiasm for the subject has waxed and waned over the past 100 years. In this century, there have been two major developments which have revolutionalized our thinking and stimulated people to get back into the field. The first in my view was the comprehensive description of phlebography
by Gunnar Bauer in 1942”. The second, and probably more significant in terms of real progress in answering many questions, was the introduction of fibrinogen tagging by Mr. John Hobbs in 196Z9. This is a landmark piece of work which has stimulated more research than any other single advance in my lifetime. We could for the first time detect the disease in its earliest stages and in an objective manner evaluate our attempts to either modify the thrombotic process or prevent it from occurring. Biomaterials could properly be placed under the heading of engineering, but I have chosen to set it aside for some obvious reasons. Clearly, vascular surgeons deal with this issue daily by inserting prosthetic devices which function with varying degrees of success. In my view, this field should be reexamined from an entirely different and new perspective given the facts as we know them. Rigid tubes will not in the long run remain a satisfactory answer to our problems as witnessed by not only ancient but recent history. Development, initial testing and prospective trials remain the challenge for the future. Unfortunately, this is a very timeconsuming multi-disciplinary problem, but we continue to work in this area as long as atherosclerosis remains the problem it is today. The fact that a vein is and remains the best arterial substitute should in part at least provide some clues for the future of research in this area. This is, of course, in many respects an endless shopping list. Yet it need not be, particularly if we want to continue to look to the future. It will require leadership of an enlightened type that will encourage young surgeons to venture into areas unfamiliar to most of us. However, we can rest assured that unless the enlightenment starts at the top of our profession, it is very unlikely to emerge from the younger members who depend upon their leaders for guidance, encouragement, inspiration, and funding. However, we all must realize that much of what I have discussed has been referred to by Dr. Lewis Thomas as “halfway technology’0 .” It represents the development of techniques to assist us in compensating for the effects of diseases whose course we can do little to alter. Unfortunately, it is very costly and time-consuming. The goal must be to move medicine away from this level of technology, and this requires new information which in turn is entirely dependent upon ongoing research. Surgeons can and must be active in these efforts, but it will require the three essentials of a successful career - time, hard work, and the willingness to sacrifice. In closing, I would like to dwell a bit on the famous statement by Lord Kelvin which can be seen in the Royal College of Surgeons and reads as follows: “When you can measure what you are speaking about and express it in numbers, you know something about it; but when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of
J. Biomed. Eng. 1982, Vol. 4, Juiy
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Role of technology in vascular surgery: D.E. Stmndness
knowledge, but you have scarcely, in your thoughts, advanced to the stage of science, whatever the matter may be.”
2
3
I have no idea who decided it should be seen in the Royal College, but it certainly was someone with a vision for the future. To now paraphrase Claude Bemardl’ : “Great thoughts, like great men must be torches shining at long intervals to guide us in the advance of science.” Thus in conclusion, technology is nothing more or less than tools whose proper use allows us to measure and understand what is observed. Observations, following in the wake of thoughtful hypotheses, are the foundation of science, and science must be the foundation of surgery.
7 8
9
10
REFERENCES 1
184
de Takats, G. Manageable technology. Technology, yes -technocracy, no. Amer. J. Surg. 1980,140: 270-271.
J. Biomed. Eng. 1982, Vol. 4, July
11
Wylie, E J. Presidential address: vascular surgery reflections of the past three decades. Surgery 1980, 88: 743-747. Comroe, J.H., Jr. and Dripps, R.D. Scientific basis for the support of biomedical science. Science 1976, 192: 105-111. Wyngaarden, J.B. The clinical investigator as an endangered species. N. Engl. J. Med. 1979,301: 1254-1259. Ross, R.S. The next 30 years - will the progress continue? Circulation 1980,62: l-7. Stanley, J.S. Presidential address: biomedical science and peripheral vascular surgery. Surgery 1981,89: 705-710. Buchwald, H. The scientist surgeon. Amer. J. Surg. 1981,142: 245-247. Bauer, G. A roentgenological and clinical study of the sequels of thrombosis. Acta Chir. Stand. 1942, Suppl. 74,1-115. Hobbs, J.T. External measurement of fibrinogen uptakes in experimental venous thrombosis and other local pathological states. Br. J. Exp. Pathol. 1962,43: 48-58. Thomas, L. ‘The Medusa and the Snail. ’ Medical Lessons from History, Bantam Books, N.Y., 1979, p. 132. Bernard, C. An Zntroduction to the Study of Experimental Medicine Part I, Ch. 2, Sec. IV, (Tr. by H.C. Greene), Macmillan, N.Y., 1927.
Jr.
ABSTRACT
opening
This paper is based upon a plenary
lecture presented
at the
London
of the International in September 1981.
Vascular Symposium
held in
Keywords: Surgery, technology, vascular surgery, clinical research
While it would be possible to simply catalogue the technological achievements in vascular surgery, a much broader view concerns not just technology but the place of science in this field. Advances in vascular surgery are dependent upon new and better science which can only occur with the development of new technologies. This of course, requires people with vision and ideas who are encouraged to function in an environment dedicated to change. My own views expressed here are strengthened by references to colleagues past and present who have been instrumental in moulding my thinking. Many of us have, by force of habit, come to use words in ways that often tend to fit our own biases rather than reflect their true meaning. Technology is certainly one of these words. As derived from the Greek, it consists of two parts - techne, an art or craft or technique, and logos, which simply means a systematic treatment of the problem at hand. Everyone should immediately recognize that the definition of technology fits the field of vascular surgery very well. For example, resection of an aortic aneurysm or placement of a femoro-popliteal by-pass graft requires the use of techniques to treat systematically the problem at hand. If we take the definition one step further, the user of the technique must in fact be a technician. Surgeons themselves would appear to agree with this since they commonly refer to their colleagues as either good or bad technicians according to their ability to get the job done. Physicians on the other hand use the term technician to refer to the surgeon who may operate well but is unable to think well. How often have you heard ‘he is only a technician’ implying that the brain and hands may be connected but little else. These are simple examples nology and its derivations responses depending upon case of vascular surgery, it properly applied. However,
of how the word techcan incite different one’s perspectives. In the is obviously good when we all accept that even
Department of Surgery RF-25, School of Medicine, University of Washington, Seattle, Washington 98195, USA.
a perfectly performed procedure is bad if done on the wrong patient. Thus, the use of technology is heavily dependent upon its intended use and proper application. For some reason which is difficult for me to understand, many people have come to equate technology only with devices - machines if you will. Furthermore, when used in this fashion, it is often in a very negative context, particularly when viewed in terms of its impact on society. For example, I was fortunate as a medical student to be present during one of the very first attempts at renal dialysis in Seattle which was made under the direction of Dr. Belding Scribner. The discussions which followed this truly chaotic event would have discouraged most men. Yet the idea that this was indeed feasible coupled with an available technology led to a truly great contribution. In the case of medicine, particularly as it applied to its practice, technology has come to play a prominent role in many aspects of our daily work. A glimpse of a modern operating theatre and intensive care unit is impressive, even to those of us who have closely watched the technological developments in the field over the past few decades. Yet in the minds of many, there is always a lingering doubt that these advances may in fact not be necessary if we would only pay more attention to the patient and less to the numbers. These issues have been addressed by two eminent vascular surgeons. Dr. Detakats wrote in an editorial’ in 1980, ‘Technology also breeds technocrats who in turn manage and profit by technology.’ He extols the virtue of simplicity and rightly fears the intrusion of technocrats into some areas which are best addressed by seasoned clinical judgement and not by expensive devices. This will not occur unless this control is relinquished by those of us who are closely involved. Likewise, Dr. Wylie in his presidential address to the Society for Vascular Surgery was particularly critical of the philosophy that noninvasive testing is an essential component in the evaluation of the patient with known or suspected vascular disease’.
@ 1982 Butterworth & Co. (Publishers) Ltd. 0141-5426/82/030179-06 SOS.00 J_ Biomed. Eng. 1982, Vol. 4, July
179
Role of technology
in vascular surgery: D.E. Strandness
Dr. Detakats and Dr. Wylie approach the issue of technology from slightly different directions but their conclusions are very much the same. - The present approach to most problems is good enough if we would only take time to relearn the teachings of the past. Use your own senses, they are more than adequate. - Unfortunately, this is obviously not true given the knowledge we have gained over the past few decades. While there is always a place for concern we need more and better technology, not less. Is there any reason to believe that vascular surgery should not continue to progress along with the rest of the scientific community? We must of course define how technology relates to science and what its role and impact might be. The essence of science is the statement of an hypothesis following which systematic observations are made to determine whether or not the hypothesis is consistent with the facts. Technology on the other hand is a means to a particular end and involves finding answers to questions such as “how much”. The emphasis of technology is on methods. For example, we may want to know the peak flow velocity in the internal carotid artery and develop a method of measuring it. Thus, science and technology need not go hand in hand and frequently don’t. However, technology is playing an increasingly important role in the process of scientific discovery which is that of defining and redefining the areas in which the key scientific questions can be asked. Today, science is very dependent upon technoIogy and not the other way around. If this is in fact true, what can we do to prepare ourselves for the future? If medicine is to remain alive as a discipline devoted to scientific inquiry, we must be willing to re-examine the past while always looking to the future. The history of the medical profession is a complex, interwoven series of technological and scientific advances fostered by the genius of single individuals. Great ideas in medicine, as in the arts, are rarely the result of the decisions or deliberations of a committee but of individuals who observed things other people missed and then asked the critical question, “why?” The giants of our profession who brought US to this day had the capacity to ask key questions and then attempt to answer them by the use of available technology. We can still benefit by examining the history of vascular surgery because each great contribution with few exceptions was inspired by the work, and most importantly by the ideas, which preceded it. Progress in medicine has always been unpredictable. There are often long, quiescent periods which are suddenly interrupted by times of great interest and activity. The onset of renewed activity is usually heralded by some fundamental breakthrough or advance in technology which has opened the door to those willing to look.
180 J. Biomed. Eng. 1982, VoL 4, July
In 1976 Comroe and Dripps3 investigated the top 10 advances in cardiovascular and pulmonary medicine over the past 30 years (Table 1). With the exception of the prevention of poliomyelitis, each of these are relevant to those of us who practice vascular surgery today. As each of these are examined, it must be clear that technology played a critical role in these advances. While there is no doubt that the ideas for these advances originated in well prepared and thoughtful minds, the necessary technology was either there in place or ripe for development. This has and will for the future remain the pattern for new advances in the diagnosis and treatment of cardiovascular disorders. Comroe and Dripps also attempted to profiIe the research, and in particular determine the goal, of those responsible for the scientific and technological breakthroughs. As noted in Table 2,62% of the research involved some element of basic investigation. At least 41% was not clinically oriented at the time the work was done. They were able to identify 529 essential or key articles that were responsible for the new change in direction. This would average only 19 publications per year over this time span. It would of course be nice if it were possible to preselect the successful scientist but of course this is not possible. We require bright people in large numbers because the process of scientific discovery is by its nature very inefficient. Thus most of us who work in new areas will be forced to contribute most heavily to the journal of negative results moving aside for those few who will ultimately pave the way toward major breakthroughs. Given these considerations, what are the prospects for the future? Unfortunately, they are of great concern. Wyngaarden in 1979 published an article entitled ‘The Clinical Investigator as an Endangered Species4 .’ The number of physicians involved in research declined from 46% to 20% in just nine years. The number of physicians seeking research training dramatically declined in six years, from 4600 to 1790 with 70% of the budgeted positions unfilled. As stated by Dr. Richard Ross ‘The shortage was one of applicants, not opportunities5 . These are frightening statistics if we believe the future is important. This decline in research is of major concern not just in the United States but appears to be worldwide. Furthermore, there is an interesting tendency even by some leaders in the field to ridicule the scientist and academic physician as one who really does very little that is useful. They are satisfied with the practice of vasTable I Top ten advances
in the past thirty
years3
Cardiac Surgery
Oral Diuretics
Vascular Surgery
Intensive Care Units
Drug Treatment Hypertension
Chemotherapy
Cardiac Resuscitation
Diagnostic Methods
Medical Treatment Myocardial Ischemia
Prevention of Poliomyelitis
Role of technology
Table 2 Profile of research which led to major advances3 Basic - Not ClinicallyOriented
36.8%
Basic - Clinically Oriented
24.9%
Not Basic
21.2%
Review and Synthesis
1.8%
Development
- Research
3.9%
Development
- Clinical
11.4%
cular surgery in 1981 and often extol present accomplishments as proof that this is indeed the case. One aspect of this problem was put in proper perspective by Dr. James Stanley in his presidential address to the Midwestern Vascular Society. He stated: ‘Decisions based continually on our own biases are unacceptable, especially if reasonable biomedical research would afford a more rational clinical practice6 .’ I believe what Dr. Stanley is asking for is more surgeons to become interested in science. The scientist surgeon was described by Dr. Henry Buchwald in 1981 in the following terms: ‘He asks why in addition to how. Though he seeks to be a master of his technical craft, he is not satisfied to perform without understanding. Rapidly, often with great disillusionment, he learns that the answers to the ‘whys’ are frequently based upon shaky foundations, little more than custom and faith. A codification of repetitive practice is not science.’ . . . ‘Today’s research needs intricate and sophisticated instrumentation for the testing of hypotheses’ .’ This is true since many, if not most, of the simple experiments have been done. How much biomedical research devoted to vascular disease is being done within the surgical community? The programs of our meetings reflect current activities throughout the world as well as any single barometer. The program of a recent meeting of the International Society of Surgery included 198 abstracts. There were 8 papers (4%) devoted to vascular disease with only one being of a truly experimental nature. At the last meeting of the vascular societies in America, there were four papers (two vascular, two cardiac) which could be classified as basic research. This represented 9% of the total program. The remaining contributions were clinical papers. These are disquieting statistics, and what has happened is already having a serious impact on the attitudes of young investigators. If societies continue to emphasize the purely clinical papers, then we are truly in a rut which is nothing more than a grave that is open at both ends. There is little doubt that the social and professional climate both inside and outside the academic community has profoundly affected the trends in both basic and clinical research. Early in my career, institutions could be divided into those that provided a research opportunity as a required part of clinical training, and to those interested in a rigid, lock-step approach to specialty training. This has all changed
in vascukar surgery: D.E. Strandness
now, and with few exceptions, clinical training is designed only to meet the requirements necessary for certification. If the emphasis is only on clinical training, then the future is bleak. Another area to examine which always reflects current attitudes and practices is the journals in which we present our work. Nearly all of us are guilty of liking to see our name in print. This insatiable appetite on the part of our profession has led to the widespread proliferation of publications which cross our desks every day. For those in academic life, it is the key to survival and promotion, but unfortunately acceptance for publication cannot always be equated with quality. I have been as guilty as anyone in this regard, but I am becoming increasingly concerned by what I read. Most papers would not meet the requirements of even an elementary course in statistical design. About 10 years ago I was counseled by a wellknown surgeon to send my best work to non-surgical journals. This advice was given for a variety of reasons. First, I would probably find out very quickly whether the work had any merit and second, I would receive back a critical and constructive review. I have heeded his advice to some degree, and I would concur with his conclusions. If you really want to find out how well your work has been done, I can provide a list of journals who will put your work to the acid test of careful scrutiny, and they are not by and large surgical journals. The picture which I have painted to this point is bleak indeed, and I will frankly admit that I am discouraged by what I see. There are however some hopeful signs on the horizon. I spend a considerable amount of my time travelling throughout the world. Every place I go I find young surgeons, physiologists, and engineers who are eagerly trying to find answers to old and new questions. The amazing thing is their willingness to spend extra time, often at low pay, beyond that required for clinical training to develop competence in areas not intimately related to their primary discipline. They sense, often better than I do, the need to be different, to try new approaches and to develop expertise in areas of research that will set them apart from their peers. E’urthermore, they are willing to sacrifice the only non-returnable commodity we all have - time - to prepare themselves for the future. If I had to describe their attitude in a single phrase it would be - a deep dissatisfaction with the present. If we ignore their needs and concerns, then there will be no future other than the same repetitious recountings of the present. In my view, the development of a scientific approach combined with the proper application of technology to research problems is the only hope for the future. Without acquiring competence in allied disciplines, vascular surgeons and vascular surgery will have a very limited future. Certainly we can continue to train people to operate and do it well, but if this is our only goal, the speciality will soon lose the vitality which is so essential for growth.
J. Biomed. Eng. 1982, VoL 4, July 181
Role
of technologyin
~osculor
surgery:
D.E.Strandness
hr attempting to approach new problems, the technology required to do so may be very complex and out of reach of the average academic surgeon unless he or she is willing to spend extra time to become competent in more than one area. We must also recognize that we are living in a time when collaborative research is essential for the solution to most of our problems. However, I firmly believe that collaborative research of the best kind requires a considerable understanding of the problems by all participants. It is not sufficient to do this type of research at a distance by using other people to simply fill in the gaps and plug the holes. Those surgeons preparing for the future will have to become increasingly familiar with new technologies if they want to make meaningful contributions, and unfortunately this takes time. Of course, we all must at some point decide where the future lies, and how we can best satisfy both our personal and professional goals. In the final analysis, the future always boils down to having ideas. This is as we must recognize the most difficult problem of all. Once the decision is made to pursue an academic career, what technologies might be essential in the development of an adequate background? The list of specifics is of course long, but there are general areas that are of obvious importance which are shown in Table 3. As you will note, those listed are in reality disciplines to which people may devote entire careers. Some of you may well say that surgeons have no business working in these areas, but you are wrong. It is possible for surgeons to work in these areas and become knowledgeable enough to stand toe to toe with their colleagues in finding answers to questions. If we adopt the the philosophy that surgeons must remain surgeons and not step outside their field, there will be no future except continued excellence in the operating theatre, and while this is vitally important, this is much too short sighted. The result will be less applied research in the field and a greater assumption of this responsibility by other disciplines. This clearly is what is happening in cardiac surgery even though surgeons were the pioneers in many aspects of the field and put it where it is today. Epidemiology and biostatistics are not only important but essential if we are to plan good clinical trials. Surgeons must come to grips with the fact that very little emphasis has been pIaced on this area by our specialty. Reports on the results of Table 3 Disciplines growth
utilizing
technologies
essential
for
Epidemiology and Biostatistics
Cell Biology
Bioen&eering
Thrombosis and Haemostasis
Physiology
Biomaterials
Computer Science
Pharmacology
182
J. Biomed. Eng. 1982, VoL 4, July
surgical therapy are with few exceptions a statistical disaster which we all must recognize. If trials are to be meaningful, they must be carefully designed at the start - not analysed after the fact. The technology which is available and used in these disciplines is not beyond our reach, and we must start learning it. What have the retrospective analyses so commonly used by surgeons done for us? They have resulted in chaos and confusion and lead to meaningless and conflicting conclusions. Bioengineering is of course engineering applied to biological problems. It has extended itself into nearly every area of medicine and is an ideal area for surgeons to become knowledgeable. My own case is one in point. I am not an engineer, but I am familiar enough with the field so I can converse in a fairly intelligent manner about problems of mutual interest. It took me three years after completion of my residency to feel comfortable in this relationship. During this period, I devoted 75% of my time in accomplishing this goal. The technological advances provided by bioengineers working in concert with clinicians have been phenomenal and have had an impact on nearly every aspect of our research and practice. Some of the developments, such as the Gruntzig balloon catheter, are already modifying our approach to selected patients with arterial occlusive disease. Other advances, such as in the area of ultrasonic imaging and analysis of flow patterns, are permitting for the first time methods of identifying and following patients with disease of the carotid bifurcation. We now have the tools available to evaluate the natural history of atherosclerosis in this area and answer some critically important questions which are continually before us. Expertise in the physiology of the circulation would seem to be essential for every surgeon who assumes the responsibility for the diagnosis and treatment of patients with vascular disease. This is a critically important area where each of us can continue to make meaningful observations. Yet much of the confusion with regard to vascular disease is due to a lack of appreciation of the known pathophysiological mechanisms. However, the techniques that are available to study the circulation have become increasingly complex and require considerable time to master. There are so many exciting areas in which to work, it is a shame that surgeons aren’t playing a more active role. A few examples come to mind which offer great challenges, yet if successful would contribute in a major way to our understanding of important problems. It is well recognized that atherosclerosis of the carotid artery tends to be confined to the carotid bulb with remarkable sparing of the internal carotid only a few centimeters away. Evidence is accumulating that the flow patterns that occur across this complex bifurcation may play a role in the pathogenesis of atherosclerosis. Up to the present time, this could be studied only in a model system, but we now have
Role of technology in vawuhs surgery: D.E. Strandness
the technology available flow patterns at discrete bifurcation in humans.
to describe in detail the points across the carotid
Another important area which is really untouched, relates to the physiology of the collateral circulation. These intriguing vessels, that are the surgeon’s best friends, are begging to be studied. Even today, our knowledge concerning the function of these vessels is virtually nil. In fact, we are forced to conclude, as John Hunter did, that “vessels go where they are needed.” The problem of unravelling why or how these bypassing conduits get their messages is not a trivial one but is certainly deserving of the attention of several lifetimes. Computers are here to stay, and we must more actively incorporate this technology into our efforts. Computer technology combined with statistical expertise provides us with very powerful tools. They can handle, store and retrieve immense amounts of data very quickly. For clinical trials, analysis of complex data and statistical analysis, they are absolutely essential. With the rapid progress in microelectronics, the versatility and memory capacity has increased dramatically, while there has been a decrease in price. It is now possible to obtain “small” computers (in physical terms) with capabilities unheard of even ten years ago. We must become familiar with these aids, since they will not only save us considerable time but will also make the whole area of data management in surgery available to us at relatively low cost. Cell biology is obviously a very broad field whose major focus is to describe changes at the cellular level to a variety of stimuli. For example, there is an extraordinary amount of work being done in the area of atherosclerosis as it relates to the response of both endothelial and smooth muscle cells to injury. A pressing problem is vascular surgery relates to the issue of graft failure and those factors which lead to the development of the commonly observed pannus at the distal anastomoses. A great deal of work needs to be done here to elucidate the causes for this problem and determine if we can modify or prevent this from occurring and prolong the life of an implanted graft. The field of thrombosis and haemostasis is of obvious importance and interest to the surgeon. One need only examine the problem of acute venous thrombosis to assess the impact of technology on interest in the field and the dramatic progress which can follow the introduction of a single observation. While deep venous thrombosis has always been considered a major medical problem and is constantly with us, interest and enthusiasm for the subject has waxed and waned over the past 100 years. In this century, there have been two major developments which have revolutionalized our thinking and stimulated people to get back into the field. The first in my view was the comprehensive description of phlebography
by Gunnar Bauer in 1942”. The second, and probably more significant in terms of real progress in answering many questions, was the introduction of fibrinogen tagging by Mr. John Hobbs in 196Z9. This is a landmark piece of work which has stimulated more research than any other single advance in my lifetime. We could for the first time detect the disease in its earliest stages and in an objective manner evaluate our attempts to either modify the thrombotic process or prevent it from occurring. Biomaterials could properly be placed under the heading of engineering, but I have chosen to set it aside for some obvious reasons. Clearly, vascular surgeons deal with this issue daily by inserting prosthetic devices which function with varying degrees of success. In my view, this field should be reexamined from an entirely different and new perspective given the facts as we know them. Rigid tubes will not in the long run remain a satisfactory answer to our problems as witnessed by not only ancient but recent history. Development, initial testing and prospective trials remain the challenge for the future. Unfortunately, this is a very timeconsuming multi-disciplinary problem, but we continue to work in this area as long as atherosclerosis remains the problem it is today. The fact that a vein is and remains the best arterial substitute should in part at least provide some clues for the future of research in this area. This is, of course, in many respects an endless shopping list. Yet it need not be, particularly if we want to continue to look to the future. It will require leadership of an enlightened type that will encourage young surgeons to venture into areas unfamiliar to most of us. However, we can rest assured that unless the enlightenment starts at the top of our profession, it is very unlikely to emerge from the younger members who depend upon their leaders for guidance, encouragement, inspiration, and funding. However, we all must realize that much of what I have discussed has been referred to by Dr. Lewis Thomas as “halfway technology’0 .” It represents the development of techniques to assist us in compensating for the effects of diseases whose course we can do little to alter. Unfortunately, it is very costly and time-consuming. The goal must be to move medicine away from this level of technology, and this requires new information which in turn is entirely dependent upon ongoing research. Surgeons can and must be active in these efforts, but it will require the three essentials of a successful career - time, hard work, and the willingness to sacrifice. In closing, I would like to dwell a bit on the famous statement by Lord Kelvin which can be seen in the Royal College of Surgeons and reads as follows: “When you can measure what you are speaking about and express it in numbers, you know something about it; but when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of
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Role of technology in vascular surgery: D.E. Stmndness
knowledge, but you have scarcely, in your thoughts, advanced to the stage of science, whatever the matter may be.”
2
3
I have no idea who decided it should be seen in the Royal College, but it certainly was someone with a vision for the future. To now paraphrase Claude Bemardl’ : “Great thoughts, like great men must be torches shining at long intervals to guide us in the advance of science.” Thus in conclusion, technology is nothing more or less than tools whose proper use allows us to measure and understand what is observed. Observations, following in the wake of thoughtful hypotheses, are the foundation of science, and science must be the foundation of surgery.
7 8
9
10
REFERENCES 1
184
de Takats, G. Manageable technology. Technology, yes -technocracy, no. Amer. J. Surg. 1980,140: 270-271.
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11
Wylie, E J. Presidential address: vascular surgery reflections of the past three decades. Surgery 1980, 88: 743-747. Comroe, J.H., Jr. and Dripps, R.D. Scientific basis for the support of biomedical science. Science 1976, 192: 105-111. Wyngaarden, J.B. The clinical investigator as an endangered species. N. Engl. J. Med. 1979,301: 1254-1259. Ross, R.S. The next 30 years - will the progress continue? Circulation 1980,62: l-7. Stanley, J.S. Presidential address: biomedical science and peripheral vascular surgery. Surgery 1981,89: 705-710. Buchwald, H. The scientist surgeon. Amer. J. Surg. 1981,142: 245-247. Bauer, G. A roentgenological and clinical study of the sequels of thrombosis. Acta Chir. Stand. 1942, Suppl. 74,1-115. Hobbs, J.T. External measurement of fibrinogen uptakes in experimental venous thrombosis and other local pathological states. Br. J. Exp. Pathol. 1962,43: 48-58. Thomas, L. ‘The Medusa and the Snail. ’ Medical Lessons from History, Bantam Books, N.Y., 1979, p. 132. Bernard, C. An Zntroduction to the Study of Experimental Medicine Part I, Ch. 2, Sec. IV, (Tr. by H.C. Greene), Macmillan, N.Y., 1927.