Digital health company Celero Systems is developing an electronic pill that can measure heart rate, breathing and core temperature – from the human stomach. As a first step, the company envisions people with ongoing conditions using the digital capsule to monitor their vital signs at home. But in the future, they hope to use it as a kind of internal emergency response system for drug-related overdoses.
In a small clinical trial published in November, the company tested the device in people with sleep apnea, a condition in which breathing stops and starts periodically during the night. To get a proper diagnosis, people often have to spend the night in a hospital, where they are covered with electrodes that measure their heart rate, breathing, muscle twitching and brain activity: an extensive evaluation called polysomnography. This is a recipe for a crappy night’s sleep, whether you have apnea or not.
Patients can instead opt for an at-home test, wearing a breathing monitor on their finger overnight. But this can still cost hundreds of dollars, and it’s not always accurate. These wearables cannot measure breathing directly, but only variations in heart rate that are likely caused by breathing. But a pill in the stomach cannot fall off and can measure lung movements internally.
Celero’s monitoring pill isn’t really a “pill” in the traditional sense of the word: it’s a biocompatible plastic capsule, about the size of a large multivitamin, filled with tiny sensors, a microprocessor, a radio antenna, and batteries. Before joining Celero Systems, CEO Ben Pless worked primarily with medical implants, including one of the first implantable defibrillators. But ingestible devices, or digital pills, have always intrigued him because, he says, “you could get into the body without surgery.” Ingestibles offer many of the same benefits as implantables (they’re unobtrusive and you can’t forget to wear them), “except you implant them with a glass of water instead of a surgeon,” he says.
The capsule remains intact throughout its journey through the digestive system, keeping all electronics safely contained until it ends up in the toilet a few days later. Meanwhile, all measurements are sent wirelessly to a laptop, where a researcher, doctor or even the patient can access them. To Pless’s knowledge, Celero’s ingestible device is the first to measure cardiac and respiratory activity in humans.
For the study, ten sleep apnea patients from the Medicine Sleep Evaluation Center at West Virginia University (WVU) took the pill before their regularly scheduled sleep study so researchers could see how the pill’s dimensions compared to a polysomnogram, the current gold standard. It was almost as accurate, only off by about one breath per minute – more than capable of detecting respiratory depression. No one reported any side effects or discomfort, and post-test scans confirmed that all pills were swallowed safely within a few days.