Journal of Biomechanical Science and Review Paper. Engineering. Bioengineering: A Half Century of Progress, But Still Only a Beginning*

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1 Science and Review Paper Engineering Bioengineering: A Half Century of Progress, But Still Only a Beginning* Robert M. NEREM** ** Parker H. Petit Institute for Bioengineering and Bioscience Georgia Institute of Technology 315 Ferst Drive, N.W. Atlanta, GA , USA robert.nerem@ibb.gatech.edu Abstract In the last half century the modern era of biomedical engineering has emerged, and with this there has been a technological revolution in health care. In parallel biology has undergone a revolution, and this biological revolution now is demanding an engineering revolution. With this there has been the emergence of a biology-based engineering, what this author calls bioengineering. With this we are seeing a revolution in engineering education, and today in the U.S. alone there are more than 70 departments. This revolution, however, is global in nature with exciting developments taking place in Europe and Asia as well. Other more traditional engineering fields also have recognized the importance of the bio world. The medical device and diagnostics in industry also is changing due to the convergence of the biological revolution with it, and there will be new biology-based industries, where in the future there being just as many applications outside of the medical field as within it. Thus, as we move further into the 21 st century, the changes in bioengineering will be just as dramatic as those of the last 50 years. Key words: Bioengineering, Medical Device and Diagnostics Industry, Engineering Education, a Biology-Based Engineering Introduction *Received 11 Aug., 2006 (No. R-06-B004) [DOI: /jbse.1.2] Although there are examples of engineering approaches being applied to problems in medicine and biology that date back hundreds of years, it was only in the middle of the last century that the modern era of biomedical engineering began. Furthermore, the development of this field has accelerated over the last 25 years (1). In parallel and over the same half century, biology has been totally revolutionized. This biological revolution now is demanding an engineering revolution, and with this there is the emergence of a truly new engineering discipline, a biology-based engineering, what this author calls bioengineering (2). The discipline of bioengineering includes the field of biomedical engineering, and some use the term biological engineering for this new discipline. The primary area of application of bioengineering today is to problems in medicine and biomedical research (3). Thus, for many the terms bioengineering and biomedical engineering are used interchangeably. We will, however, increasingly see applications outside of the biomedical arena, and it again must be emphasized that the emerging biology-based engineering discipline is bioengineering. What has happened in the last fifty years? What are the origins of engineering 2

2 education in this area? What about the future? This is what will be addressed by this article, and we start with the beginnings of the medical device and diagnostics industry. A Technological Revolution in Healthcare The medical device and diagnostic industry is today a major factor in the economy of the world. Based on recent data, the U.S. market alone is $80 billion and the worldwide market more than twice that. Ninety percent of this is in the medical device/implant area. It is an industry which invests seven percent of sales in research and development, and at the same time is characterized as one where 80 percent of the companies have 100 employees or less. Even so it is a large industry with 350,000 employees, this just in the U.S., and the U.S. Department of Labor projects a 26 percent growth in jobs by 2010, almost four times the growth rate of engineering jobs overall. Furthermore, although this industry has in the past hired traditionally trained engineers, e.g. electrical engineers and mechanical engineers, this is changing. This is because of the advent of combination products, e.g. the combination of a device and a drug or a device and a biologic and in the future tissue engineered products that will be surgically implanted like a device, yet have biological activity. This has lead to the need for engineers who not only have the engineering tools, but also have been able to integrate biology into their engineering. The emergence of this industry is intimately tied to the advances in technology as applied to healthcare. In the field of diagnostic imaging, such technologies as computer assisted tomography (CAT), magnetic resonance imaging (MRI) and ultrasound have relegated exploratory surgery to a method infrequently used today. At the same time that these imaging modalities have emerged, we also have seen a variety of devices/implants introduced. These include implantable pacemakers and defibrillators, prosthetic heart valves, vascular stents, orthopedic implants, intraocular lenses, implanted drug pumps, and neurological stimulators, as well as many other devices. A few years ago, the National Academy of Engineering in the U.S. established the Fritz and Delores Russ Prize as a Nobel-type award for contributions in bioengineering. This prize is given every other year, and it was first awarded in 2001 to Earl Bakken and Bill Greatbach, two pioneers who not only made possible the first implantable pacemaker, but their work really launched the medical device industry. A possibly even more interesting story is the one associated with Dr. Wilhelm Kolff, the 2003 Russ Prize winner. Kolff did his early work in Nazi-occupied Netherlands where under the most difficult of conditions, he fashioned the first kidney dialysis machine. This pioneering work on the replacement of organ function opened up new vistas, and Kolff went on to work on oxygenators, the artificial heart, and more recently the artificial lung. The importance of technology in healthcare, and in a broader sense the role of engineering in the biomedical arena, has recently been enhanced by the formation in the U.S. of a new institute at the National Institutes of Health (NIH), the National Institute for Biomedical Imaging and Bioengineering. This new institute, established in 2001, includes as part of its mandate the development of technology and is making an effort to reach out from NIH to industry. Although it is the smallest institute budgetarily within the NIH family, it has the potential of making engineering an equal citizen on the NIH campus. Thus, in the last fifty years there literally has been a technological revolution in healthcare. With this a major global industry has emerged, a new institute at NIH has been established, and millions of patients have been impacted. The emergence of this industry, however, is only part of the story. Biomedical Engineering Education As noted previously, in the early days it was biomedical engineering, and it involved the application of traditional engineering to problems in medicine and the life sciences. As 3

3 far as the beginning of academic programs, institutions with early initiatives in the U.S. included Drexel University, the University of California, San Diego, the University of Michigan, and the University of Washington. The real pioneers, however, were those institutions that established the first academic departments. The very first in the U.S. was the University of Virginia in 1967, then Case Western Reserve University in 1968, Johns Hopkins University in 1970, and Duke University in It should be noted that all four of these represent a situation where a biomedical engineering department was established as part of a relatively small engineering school, but at a university where there was a major medical school. In fact, even as recently as 15 years ago, there was little correlation in the U.S. between a list of the top ten engineering schools and the top ten biomedical engineering programs. This is all changing, however, and today there are more than 70 departments in the U.S., at least at last count. Whether called biomedical engineering or bioengineering, the focus of these departments is largely on the medical field. They are establishing unique academic programs, and they are attracting the best and brightest students. Why this explosive growth in the U.S. in academic departments? This is probably for two reasons. First is the biological revolution, and my comments on this will be delayed until the next section. The second reason is The Whitaker Foundation, established in 1978 from the estate of Uncas Whitaker, the founder and chairman and CEO of Amp, Inc., an electronic connector company (4). Mr. Whitaker during his life had a real interest in engineering and its possible role in medicine. Following his death and with the establishment of the foundation, there began an investment by The Whitaker Foundation in what became a portfolio of programs, ones ranging from young investigator grants to programs designed to build an academic infrastructure. In regard to the latter, The Whitaker Foundation recognized that, for biomedical engineering to be a permanent part of the academic infrastructure at universities, it needed to have departmental status. Over the years a total of $750 million has been invested, and as a result there are now and as noted earlier more than 70 departments, with most of the major engineering schools having established one. Although the Whitaker Foundation is going out of business at the end of 2006, it has made its mark in creating permanence for biomedical engineering at U.S. universities. Even though the rest of the world has not been able to benefit from funding of a Whitaker-type foundation, there are places in the world that also represent pioneers in biomedical engineering education. This includes Strathclyde University in Scotland, Linköping in Sweden, and several places in the Asia-pacific region. In fact, with the literal technological explosion taking place in China and India and with advanced research in Japan, Korea, and Singapore, there are new educational programs emerging and the development of bioengineering education is becoming a global enterprise. The Emergence of a Biology-Based Engineering In spite of the focus over the last half of the twentieth century on the field of biomedical engineering, i.e. a medically-based engineering, it is bioengineering, a biology-based engineering, that is emerging as a new discipline (2). Just as engineering has physics-based disciplines, e.g. electrical engineering and mechanical engineering, and also a chemistry-based discipline, i.e. chemical engineering, for the biotech twentieth century there is a need for a biology-based engineering discipline, i.e. bioengineering. Furthermore, although the focus of The Whitaker Foundation has been on the field of biomedical engineering, it is a biology-based engineering discipline that they in fact have fostered. Important in this has been the biological revolution, which started at the beginning of the last century with the advent of cell culture. Biology was further revolutionized in the 1950s with the discovery that DNA is a double helix, accelerated in the 1970s with the introduction of recombinant DNA technology, and more recently with the human genome 4

4 project and soon the proteome and then the physiome. Biology is becoming a quantitative science, an information science, one requiring engineering analysis and a systems approach. Furthermore, advances in molecular and cell biology continue at a very rapid pace. It is this biological revolution that literally demands an engineering revolution and the emergence of bioengineering. In this new engineering discipline, biology is the central science, and the challenge that the faculty in these new departments are facing is how to integrate the biology and the engineering, into their educational program. Those being educated in this new biology-based engineering discipline need to know how to use the advanced tools of both biology and engineering. Furthermore, they need to be able to integrate their knowledge across the biological scales, i.e. from the molecular to the organ to the whole body levels. In the future, e.g years from now, there will be as many applications outside of the medical field as within it. As this happens, these new departments with a biomedical focus will morph into much more broadly oriented, biology-based departments, and in the U.S. this may provide the opportunity for a coming together of these departments and those that are morphing out of the former agricultural engineering departments. These latter academic units are also many times now called biological engineering. They are somewhat at the periphery of the current activities in the development of bioengineering, as it is the departments with a focus on biomedical engineering that are providing the majority of the leadership in the integration of biology and engineering. Other more traditional engineering fields also have recognized the importance of the bio-world, and this is an important trend as the application of engineering to problems in medicine and biology provides opportunities for all of engineering, not just bioengineering. Mechanical engineering departments have long provided a primary home for those interested in biomechanics. This includes the application of mechanics at the molecular and cellular levels. Some chemical engineering departments in addition have been highly active in bioengineering research, and in the last few years, with the changes taking place in the chemical and petroleum industries, the academic departments in chemical engineering have been moving to reposition themselves. This has manifested itself in many of these departments changing their name, e.g. to chemical and biomolecular engineering or to chemical and biological engineering. With this will come some modification in the curriculum of chemical engineering departments; however, it will be the bioengineering departments that will provide the leadership in the integration of biology and engineering. As a new discipline, bioengineering faculty are still seeking the best way to educate students. Whereas many faculty in traditional engineering departments give the impression that they know what they should be teaching and how best to teach it, faculty in bioengineering are still struggling with these issues. In this author s opinion, engineering educators have always done a good job in teaching analysis; however, with the exception of a few design courses, little attention has been and is being paid to bringing out the creativity in students and to motivating their self-learning. In bioengineering, however, a variety of educational modes are being explored, including problem-based learning. It may be that not only are we seeing the emergence of a truly new engineering discipline, but it will be one that will revolutionize in a broader way engineering education. These changes need to empower students to take ownership of their learning. It also must include bringing a real diversity to the manpower being educated, and already in the U.S. bioengineering is attracting both women and underrepresented minorities/ethnicities into its degree programs. The Changing Face of Industry It has been said that advances in biology will define scientific progress in this twenty-first century. Biology, however, is too important to be left to the biologists for the continuing and significant advances in biology provide a foundation for many applications 5

5 and the involvement of many other fields. Thus, advances in molecular and cell biology will not only define scientific progress, they will revolutionize how we engineer products in this biotech century and create entire new industries. An example of this is the medical device/implant industry where today products are largely made from synthetic materials. Virtually every company in this industry is involved in the development of combination products and sees tissue engineering and regenerative medicine as a part of their future. These biology-based technologies, ones based on living cells and natural biological materials, are focused on the repair, replacement and/or regeneration of tissues and organs. In incorporating these new technologies, the medical device/implant industry potentially will be totally revolutionized, with medical products increasingly being of a combination nature, with an early example being the drug eluting stent. The impact of the biological revolution on industry will undoubtedly be much broader. Although the nature of new industries cannot be predicted, there will be an enormous expansion in ones that are biology based. Maybe it will even be possible in the future to make paper through bio-processes rather than cutting down trees. Whatever the nature of these new biology-based industries, they will need engineers. In fact, in this biotech century bioengineering is too important to be left to the bioengineers. As noted earlier, all of engineering needs to be involved, and at universities every engineering department should be doing bioengineering research. This will require new and innovative educational programs, and it also will require that a biology course join physics and chemistry as a core science subject for all engineering students. There are a few engineering schools already requiring this; however, this will need to be in all institutions, at least those who wish to be at the forefront of engineering education. The Future As we move further into this 21 st century, bioengineering will undergo changes as dramatic as those that have occurred over the past half century. There are many factors, including the already discussed changing face of industry, that will influence the future of bioengineering. Important factors in this include the major trends taking place in public health, changes in the health care system as it attempts to contain costs, the transformation of medicine to a focus on what many are calling predictive health, the continuing advances in our understanding of biology, and the development of new, truly innovative technologies. Certainly there are trends in public health that will impact all of medicine including biomedical engineering. These include a shift from acute to chronic diseases, the aging of the population in the developed world, health disparities, and emerging, even reemerging diseases. It also includes the escalation of healthcare costs, these heading in the U.S. towards 20 percent of GDP, a level that is not economically sustainable. There thus is a need to transform medicine into an enterprise that is economically sustainable. If we could intervene earlier, ideally before symptoms appear, we could reduce healthcare costs. To do this requires that we detect preclinical molecular events, this so that we can identify patients at risk. There also will be the need and the opportunity to develop new, innovative technologies. These will include technologies for diagnosis and treatment, such as molecular imaging, image-guided interventions, and those arising out of tissue engineering and regenerative medicine. It also will include technologies that will drive science, for not only does science drive technology, but the reverse is equally true, technology drives science. Finally, as noted earlier, biology is becoming an information science, and this opens up new opportunities. We need to understand quantitatively the relationship between the various elements of complex biological systems, and we will need to integrate our 6

6 knowledge across the biological scales. We also will need to develop a predictive ability, and this will require mathematical models that drive the design of new experiments and that in turn will drive the further development of the models. All of these change factors will shape the future. They also cry out for the involvement of bioengineers, in fact for leadership from the bioengineering community and from all of engineering. As a result, although we cannot predict the exact nature of the future for bioengineering, it seems clear that it is one that will be exceedingly bright. The opportunities are there, these represent significant challenges, but in addressing these, the best is yet to come. In closing, the biological revolution is demanding an engineering revolution. This will require a revolution in engineering education. Already we have seen the emergence of a truly new engineering discipline, i.e. bioengineering. This revolution in engineering education is one that not only is taking place in the U.S., but also in the rest of the world. It is also a revolution in which all of engineering, and the physical sciences as well, needs to participate. References (1) Citron, P. and Nerem, R.M., Bioengineering: 25 Years of Progress - But Still Only a Beginning, Tech in Soe, Vol. 28 (2004), pp (2) Nerem, R.M., The Emergence of Bioengineering, The Bridge, Vol. 27, No. 4 (1997), pp (3) Montaigne, F., Medicine by Design: The Practice and Promise of Biomedical Engineering, The Johns Hopkins University Press, Baltimore, Maryland, (4) Katona, P.G., The Whitaker Foundation: The End Will Be Just The Beginning, IEEE Trans Med Imag, Vol.21, No. 8 (2002), pp