Key points from article :
Almond size device can monitor respiratory rate and heart rate from inside the gastrointestinal tract.
Listens to heart sounds and lung sounds using a microphone while inside the gut.
Detects heart rate and respiratory rates of pigs accurately even when food was being digested.
Sends radio signals to an external receiver, with a range of about 3 meters.
After one or two days it goes out of the body with stools.
Can aid clinical monitoring and diagnosis, assess trauma patients and monitor soldiers at battle.
Research by MIT published in PLOS One.
