What is Biomedical Engineering?


Some people can periodically experience an abnormally low heart rate and can lose consciousness during critical life style moments such as physical activity, driving an automobile, or just walking up a flight of stairs.

The cardiac pacemaker demonstrates the tremendous intersection of a significant medical problem with several key engineering specialties and is a great example of a Biomedical Engineering solution. Briefly, electrical and computer engineering skills are used to design the electronics and programming logic which drive the device - all pacemakers are based on fully functioning microprocessors. The pacemaker is implanted inside the human body (a particularly hostile environment) and therefore must be impervious to the biological fluids and must also not cause a rejection reaction.

Thus the biocompatibility issues and the subsequent solution with engineered biomaterials were crucial to the long term success of the pacemaker. Additionally, the wires connecting the device with the heart tissue must be flexible but resilient enough to withstand the repetitive motion produced by a beating heart. Further, the wires cannot dislodge from stable sites within the heart under these same conditions. The subsequent mechanical design of the pacemaker wires has solved this problem.

The battery energy source which powers the pacemaker was originally a set of ordinary mercury cells but the need to increase energy density lead to the development of the lithium battery technology increasing the life span of the device from 12 - 18 months to 8 - 10 years. The lithium battery technology is now common place in a wide range of consumer and industrial products. Of significant note is the fact that the National Academy of Engineering has established an award for major engineering contributions which have significantly impacted society and has contributed to the advancement of the human condition - The Russ Prize. The first Russ Prize was awarded in 2001 to two Biomedical Engineers credited with inventing the cardiac pacemaker: Earl Bakken and Wilson Greatbatch. More than 400,000 pacemakers are implanted annually around the world!

History and Background

bmehistory.jpgMany disciplines are attracted to the genius of Leonardo da Vinci, but his unique combination and mastery of mechanics and anatomy poised him to be the first Biomedical Engineer with a biomechanics specialty. The discovery of electricity and current led to a charged debate between Galvani and Volta in Italy in the late 18th century. Their debate was based on observations of frog leg stimulation and contraction and hence bioelectricity formed the initial understanding of these fundamental electrical theories. As the scientific basis of medicine progressed into the 20th century devices for measuring and monitoring body functions required technical skills beyond a physician's primary clinical training. The use of X-rays to obtain images of the inside the body was also a significant technological driving force for the overlap of engineering and medicine at this time. The Professional Group on Engineering in Medicine and Biology was formed in 1948 under the auspices of several professional societies. National and international conferences were held regularly and several organizations trace their origins to this period. 

Several academic Biomedical Engineering programs trace their roots to the 1950s but were housed within traditional engineering departments. Most were in electrical engineering programs as the initial medical devices were mostly electrical or imaging oriented. As the medical community took a more "constructive" role in treating disease and injuries cardiac bypass surgery, kidney dialysis, and orthopedic implants increased the roles for biomechanics and biomaterials. Again, as medicine discovers the role of the genetic code and molecular biology for diagnosing and treating diseases the Biomedical Engineering has kept pace with development of tissue engineering, micro electrical-mechanical systems (MEMS), sophisticated drug delivery, and nanotechnologies.Biomedical Engineering Today
Biomedical Engineering is a vibrant and rapidly expanding field both in content and opportunities. As our technological infrastructure expands and our fundamental knowledge in the life sciences reaches the basic molecular level, Biomedical Engineers are poised to continue to make major advances. There are over 100 Biomedical Engineering Departments and Programs in the US. Most offer graduate degrees at the MS and PhD level, while only some of these programs offer undergraduate degrees. ABET, Inc., lists about 75 accredited biomedical/bioengineering undergraduate degree programs. Many of these are more than 25 years old, but the fact that the number of programs has more than doubled in the past 5 years and that it takes at least 4 -5 years before a program is able to apply for accreditation the outlook is for a real boom in the number of accredited undergraduate programs in the coming years. This commitment to growth in Biomedical Engineering education is concomitant with the industrial and research opportunities available to well trained graduates in the field.