Electronic stethoscope wins $50,000 award

While traditional metal and rubber stethoscopes around the necks of doctors and nurses have become a symbol of the medical profession, a USF

doctor and acoustical engineer have upgraded a version of the device for the digital age — and won a Cade Museum Prize for their invention.

Phil Hipol, engineering director at the Center for Advanced Medical Learning and Simulation (CAMLS), and Dr. Stuart Hart, an assistant professor of obstetrics and gynecology, received more than $50,000 in prize money for their electronic catheter stethoscope, or “eCath.”

The eCath is a small electronic device consisting of a sensor assembly and microphone. It can communicate information wirelessly to a computer and allows listeners to hear sounds from inside the body, Hart said. The device connects externally to any catheter, a tube inserted into the body that can be used to drain the bladder, inject drugs or allow the passage of fluids, depending on where it’s inserted.

Hart and Hipol have been working on the eCath stethoscope for the last three years. Hart said the concept for the eCath stethoscope “came out of a desire to reduce the number of bladder injuries during hysterectomies.” He said doctors injure the urinary tract 4 percent of the time during hysterectomies and 75 percent of the time, they don’t realize it or don’t know why it happened. 

Through sound frequencies, eCath can also detect whether incisions during surgery were made properly, he said.

Hart said Hipol proposed to invent something based on 20th-century sound technologies developed by the U.S. Navy.

“Back in the ’50s and ’60s, the U.S. Navy would use very sophisticated signal processing capability,” Hart said. “They could filter out the noise of the ocean and hone in on specific sounds for Russian subs, so they could actually detect where a Russian sub was heading and the depth of the Russian sub simply by sounds that the Russian sub emitted.”

Hipol and Hart applied this technology to the body, which, like the ocean, is filled with fluids, Hart said.

“What we’re doing with this device is we’re opening up a whole new field of inside-the-body acoustic monitoring,” Hipol said.

Traditional stethoscopes don’t pick up inner-body sound nearly as well because the soft tissues and bones cut off or filter out much of the sound, Hipol said. A catheter, on the other hand, conducts bodily sounds quickly and efficiently, and the device attached to the outside of the tube receives and amplifies them, he said.

“So when you’re inside the body, you have a whole richness of sound that people have never heard before,” he said. “We can associate those sounds with different physiologies or damaged organs.”

The eCath stethoscope can detect sounds from the respiratory tract and the passage of blood as well as heart murmurs and arrhythmias. The device can also be used in childbirth and delivery, Hart said.

Hart said that when a woman goes into labor, doctors routinely strap special bands around the mother’s belly to measure her contraction rate and the fetal heartbeat. But the bands tend to fall off or shift during childbirth. He said eCath could resolve this challenge.

“(Doctors or nurses could) install a urinary catheter,” he said. “Once that’s installed, (they) can actually hook up our microphone to the end of it and hear the baby’s heartbeat and what her contraction rate is.”

Hipol said the electronic stethoscope can give more precise and accurate acoustic data on when a cesarean-section is needed and prevent the mother and baby from being injured or infected.

Hart and Hipol said the prize money would help them continue researching the eCath.

“This money would really help advance the research and development of the technology and this device,” Hart said. “The eventual goal (would be) commercializing this device for use in medicine.”

The Community Foundation of North Central Florida sponsored the $50,000 prize, and an additional $10,000 worth of legal services will be provided by Edwards Wildman Palmer, a law firm in West Palm Beach.