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Biotechnology & Biomaterials

Leslie A. Geddes has invented dozens of means to prevent and treat diseases of the heart and lungs, and has trained an entire generation of biomedical engineers.

Geddes was born in Port Gordon, Scotland in 1921. He had shown a love of electronics even before his family moved to Quebec, Canada when he was still a child. At age 14, he became the youngest amateur radio operator in Canada. Geddes attended McGill University in Montreal, intending to become a doctor, like his father. After a professor convinced him to major in engineering, Geddes ended up studying --- and excelling in --- both subjects. Between earning a BS (1945) and MS (1953) in Electrical Engineering, Geddes did research in Neurology at McGill's Medical School.

Geddes then joined Baylor University's Medical College, in Houston, where he worked as a Biophysicist and then rose to Professor after earning his PHD (1959). Many of Geddes' innovations at Baylor used electrodes to monitor the human body. For example, he developed the first clinical electromyograph for diagnosing nerve damage. Geddes also invented a respiratory monitoring system for NASA, which was later modified to detect apnea in newborns. Geddes even modernized Baylor's medical pedagogy: he used his "Physiograph" recording device to introduce medical students to cardiology.

Geddes had already won a number of honors by the time he was recruited by Purdue University in 1974, becoming Showalter Distinguished Professor of Bioengineering, and Founding Director of the Hillenbrand Biomedical Engineering Center. At Purdue, Geddes has concentrated on cardiovascular devices.

In 1982, Geddes and two colleagues patented a device that detects and corrects potentially lethal cardiac arrhythmia. In 1984, Geddes and another team patented a conductivity catheter that measures cardiac output; and in 1986, Geddes co-patented a pocket-sized, personal electrocardiograph. Geddes also won many patents for improvements to the cardiac pacemaker, including the first model to increase its pace automatically when its wearer exercises.

Outside the cardiovascular realm, Geddes and yet another team earned three patents in the 1990s for a new biomaterial, small intestine submucosa, which when grafted onto tissue in need of repair completely remodels itself to mimic that tissue --- be it a blood vessel, tendon, or stomach lining --- without provoking an immune response. In total, Geddes has earned over thirty patents for both esoteric and everyday inventions: e.g., a baby pacifier that can deliver medication (1994).

Geddes is no less celebrated for his innovations in medical therapy and theory. He discovered and demonstrated precisely the optimal sites on the chest for defibrillation or pacing. He developed "electroventilation," a safer technique of artificial respiration by electrical stimulation of the nerves of the chest and diaphragm. With three colleagues, he propounded the "three laws of defibrillation," which have saved countless patients from myocardial damage.

As an educator, Leslie Geddes may have no equal in his field. In 1968, he wrote the classic textbook "Principles of Applied Biomedical Instrumentation"; he has co-authored or co-edited twenty other books, and has co-authored over 725 scholarly articles. Geddes is estimated to have taught over 2,000 biomedical engineers --- about one fifth of those now working in the US. Although he is retired from full-time teaching, Geddes still arrives at his Purdue office every morning, by 6:00 a.m., for another day's work.

[Sept. 2000]