Ingestible device measures heart and breathing rate
A new ingestible device detects breathing depression, which could help monitor people with sleep apnea or at risk of opioid overdose.
Researchers from the Massachusetts Institute of Technology (MIT; MA, USA), Celero Systems (MA, USA) and West Virginia University (WV, USA) have collaborated to develop the first ingestible electronic device that can measure heart and breathing rate from inside the gastrointestinal (GI) tract. The device could be used to help diagnose and monitor people with sleep apnea or those at risk of an opioid overdose.
“It’s an exciting intervention to help people be diagnosed and then receive the appropriate treatment if they suffer from obstructive sleep apnea,” commented first author Giovanni Traverso (MIT). “The device also has the potential for early detection of changes in respiratory status, whether it’s a result of opiates or other conditions that could be monitored, like asthma or chronic obstructive pulmonary disease.”
Diagnosing sleep disorders such as sleep apnea, which is a condition where people stop and start breathing in their sleep, usually requires an individual to spend the night in a specialist sleep clinic, hooked up to a variety of monitors.
To make the diagnosis process for sleep disorders less intrusive, the researchers set about developing an ingestible capsule that could detect breathing depression. This built upon their previous work, which involved developing ingestible sensors capable of monitoring vital signs and diagnosing GI tract conditions, such as inflammatory bowel diseases.
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The capsule they developed, which is about the size of a multivitamin, uses an accelerometer to measure an individual’s breathing and heart rate by detecting slight movements generated by the beating of the heart and the expansion of the lungs. The capsule then transmits this data to an external device, such as a laptop.
After successful animal studies, the team trialed the capsule in 10 human volunteers. The volunteers were monitored overnight using both the ingestible capsule and the sensors and monitors typically used to monitor sleep, so the researchers could compare measurements.
They found that the device accurately measured vital signs and detected a sleep apnea episode that one of the volunteers experienced. None of the volunteers showed any adverse effects from the capsule, which passed harmlessly through the digestive tract.
In addition to diagnosing sleep apnea, the device could also be useful for detecting opioid overdoses in individuals at high risk. In an animal model, the researchers showed that the device could detect respiratory depression that resulted from a large dose of fentanyl, an opioid drug.
“We know that people who have had an overdose are at higher risk of recurrence, so those individuals could be monitored more closely so that in the event of another overdose, someone could help them,” Traverso explained.
Next, the researchers are hoping to incorporate an overdose reversal agent, such as nalmefene, into the capsule, so that on detection of respiratory depression, the device would release life-saving treatment. They are also developing strategies to extend the length of time the capsules can remain in the stomach.