In the emergency room of the future, the first step to treating a trauma patient may be to get him or her to swallow a tiny stethoscope.
The best way to monitor vital signs like breathing and heart rate may be with a microphone that listens and transmits data from inside the body, say researchers at the MIT Lincoln Laboratory and Massachusetts General Hospital.
They created a pill-sized stethoscope, essentially a cell phone microphone wrapped in a plastic bullet-shaped casing, with the goal of sounding out signals without touching the skin.
“We can detect the signals all the way through the GI tract,” said Dr. Giovanni Traverso, one of the lead researchers of the study and a gastroenterologist at Mass. General Hospital and instructor at Harvard Medical School.
The team tested the almond-sized device in living pigs and described the results in a paper published in Plos One this week.
Research into smarter and smaller electronics for cellphone microphones allowed the team to assemble the hardware in the device without breaking the bank, Traverso explained.
A key innovation was developing algorithms that would distinguish important signals—the thumps of a beating heart, breaths in and out—from the noisy gurgling of the gut, and then translate them into numbers a physician can read and understand.
The idea is to refine the design of the device so that it’s fully wireless and strong enough to stick around in the stomach for an extended period of time. The first version of the device for humans, Traverso acknowledges, is likely to be designed to pass right through.
Researchers know that the stomach can be oblivious to small stowaway foreign objects. “You’re talking bigger than a burger,” Traverso said. So a microphone the size of a jellybean could be tucked away unnoticed.
Traverso is betting that related technology that has already been approved by the US Food and Drug Administration will likely smooth the passage of the ingestible scope through what can be a lengthy regulatory process.
For example, another collaborator on this study, MIT researcher Robert Langer, has been leading a exploration into pill-sized drug delivery devices that can administer measured doses over extended periods of time. And Traverso himself treats patients using a version of an FDA-approved swallowable camera that captures snapshots of the bowel.
In some sense the scopes are just one small step forward, adding a layer of sound to what was once a silent film.