BC biomedical engineer Dr. James McEwen, P.Eng., will be inducted into the US-based National Inventors Hall of Fame for his creation of the first microprocessor-controlled automatic surgical tourniquet system. Devices based on his innovations are used worldwide in close to 20,000 surgeries each day.
After completing doctoral research at Vancouver General Hospital, Dr. McEwen established its biomedical engineering department, where he investigated situations where patients suffered limb paralysis, nerve damage, and other injuries due to surgical tourniquet use. In the mid-1970s, McEwen’s research had revealed problems with mechanical pneumatic tourniquets, including an unreliable pressure-regulating mechanism and no fail-safe feature to limit maximum cuff pressure.
Dr. McEwen, who received Engineers and Geoscientists BC’s Meritorious Achievement Award in 1999, designed the tourniquet by using a computer to control the applied pressure. By 1980, he had developed a microprocessor-controlled system that was safer and more efficient than previous technology. An automatic timer provided an accurate record of inflation time, and if dangerously high or low cuff pressures were present, audiovisual alarms would activate. Safety features included automatic detection of air leakage, system integrity checks, and a backup power source.
Almost all modern tourniquet systems used in western countries are based on the work of Dr. McEwen and his colleagues, including automated surgical tourniquet systems from Zimmer Biomet.
Dr. McEwen’s many awards and acknowledgements include his appointment as an Officer of the Order of Canada, the Principal Award for Innovation from Canada’s Ernest C. Manning Awards Foundation, the Queen Elizabeth II Diamond Jubilee Medal, and the Dean’s Medal of Distinction from the Faculty of Applied Science at the UBC. He has over 240 patents and patent applications in the United States, Canada, Europe, and other countries for a wide range of medical devices in fields including orthopedics, anesthesia, ophthalmology, laboratory medicine, surgery, exercise science, and rehabilitation.
Dr. McEwen will be inducted to the National Inventors Hall of Fame at a ceremony on May 7, 2020, in Washington, DC. He will join a prestigious list of hundreds of inventors, such as Thomas Edison, Alexander Graham Bell, Nikola Tesla, Rudolf Diesel, King Gillette, and Steve Jobs.
Dr. McEwen maintains a website, tourniquets.org, which provides detailed explanations of his work and inventions.
Photo: Clare Kiernan, UBC