The greatest breakthroughs may result when explorers step off the well-trodden path of conventional wisdom, of prior art, of well-respected theory, and dare to do the unconventional. Such was the case for a team of UW researchers in the 1950s who, by pursuing non-conventional goals, not only revolutionized our understanding of the function of the heart but who also laid the foundation for an entirely new department of bioengineering in 1967 and of a new, interdisciplinary way of combining science, engineering, and medicine.
Robert F. Rushmer, who led the early studies at the UW of cardiovascular function, went on to serve as its first director of bioengineering. Rushmer recalls that during the years after the Second World War, "the tools of biological research were primitive by any standard. A notable example was the almost universal dependence on smoked-drum kymographs [paper-covered revolving drums] and mechanical levers for the study of function and control of isolated or exposed hearts of dogs."
But the development of more quantitative and sophisticated techniques accelerated after the war. Tools of physics, chemistry, and engineering increasingly were applied or adapted to studies of living organisms, and Rushmer's work was featured among those efforts. With a background in aviation medicine, he came to the UW in 1947 when the UW School of Medicine was established. Colleagues have described him as a fine teacher, a superbly organized and vigorous researcher, inclined to test rather than accept traditional findings in physiology, and inspired to develop new methods.
In the early 1950s, Rushmer and colleagues had an idea that admittedly was not conventional. They believed that studies in animals to understand the function of the heart should be carried out in live animals as opposed to carrying them out in the traditional, static way using excised hearts or exposed hearts in anaesthetized animals. They believed that the results obtained from live, active animals would be more representative of normal cardiac function.
In initial efforts, Rushmer and colleagues succeeded in showing moving pictures of blood coursing through the chambers of the heartwork that involved analyzing x-ray motion picture films called cinefluorograms. These results "challenged the generally accepted concepts of cardiac function and control," recalls Rushmer, and they suggested the need for more quantitative analysis of the heart under conditions that were as normal as possible. So a team of mainly undergraduate engineering and physics students was recruited to develop sensing devices that could be implanted in and on the heart ventricles of healthy active dogs in order to monitor changing dimensions, pressures, and blood flows of the heart and blood vessels.
The signals from these devices provided as many as 26 simultaneous measurements, including stroke volume and cardiac output, ejection velocities, and power. These measurements permitted cardiovascular function to be analyzed during all kinds of activities: exercise, eating, sleeping, as well as in cases of heart abnormalities. And the role of the central nervous system in cardiovascular control could be explored using electrodes implanted in the brain to stimulate reactions.
"This was an exhilarating period when each experiment disclosed new and unsuspected aspects of cardiac responses," notes Rushmer. "These spectacular technical achievements placed the laboratory at the forefront of bioengineering enterprises between 1947 and 1956."
Activities in bioengineering expanded to include the development of diagnostic devices for clinical medicine. The first of those was a portable ultrasonic Doppler flow meter to measure peripheral vascular blood flow and fetal heart action, developed by Eugene Strandness, Rushmer, and colleagues (see Ultrasound) and commercialized by the Smith-Kline Instrument Company in 1964--an advance that set the stage for the development and commercialization of many technologies in cooperation with local industry in the years to come.
Recognizing that such an interdisciplinary program could not be adequately accommodated in any one department, the Center for Bioengineering was established in 1967 in an arrangement unusual for its time. The program was managed by both the College of Engineering and the School of Medicine. Reflects Rushmer: "The enthusiastic and unremitting administrative support by four generations of deans of both medicine and engineering was coupled with widespread faculty involvement, leading to the development of the largest and most diverse bioengineering program in the country."
In the early 70s, representatives of local industries were invited to the University to review technical developments in bioengineering. The purpose of the day-long meeting was to apprise them of emerging techniques and technologies with commercial potential for clinical applications. Rushmer recalls that "this meeting was so enthusiastically received that Industrial Associates Days were continued yearly thereafter."
Bioengineering projects over the years led to the creation of Lawrence Medical Systems and MedPacific, and to collaborative work with PhysioControl Corporation, Eli Lilly, SeaMed, CooperVision, and other industrial affiliations.