"A crucial technology improvement in this new generation health patch is the integration of a wide range of sensing capabilities into imec's MUSEIC V3 system-on-chip solution. As a result, the device is almost an order of magnitude cheaper, while the high degree of integration makes it much more energy-efficient. The significant cost reduction means that the patch can now be used as a disposable solution, an important benefit for medical treatment," says Bernard Grundlehner, System Architect – Connected Health Solutions at imec the Netherlands.
The patch uses a mix of skin friendly and biocompatible materials. The base substrate is a very thin, flexible and elastic TPU material. Most of the electronic functionality is realized using printed electronics technologies and integrated dry electrodes provide a stable and high-quality electrical connection to the body. A comfortable silicone adhesive is used to provide long-term adhesion at high comfort. "Completely watertight, the new health patch is built for maximum user comfort and can be worn for up to seven days before needing to be replaced", explains Prof. Jeroen van den Brand, program director printed electronics, TNO.
Environmentally friendly battery
To limit the ecological footprint of the single-use patch, imec researchers have collaborated with Maxell Ltd. to develop an environmentally friendly battery which does not contain any toxic substances. Additionally, the MUSEIC V3 also improves the overall energy-efficiency because of its low-power signal acquisition. While competing solutions generally advertise a battery life of 3-4 days, imec's solution has a battery life of over 7 days, in many cases even longer, depending on the specific configurations
For patients, a single, disposable patch that can be worn for several days is more convenient and can reduce hospital visits as it no longer needs to be returned after use. This is particularly important for chronically ill patients as it provides an affordable, single-use device that can be easily used to monitor their vital signs and physical activity at home. Easy to apply and comfortable to wear for long periods of time, it enables patients to perform their normal daily activities with minimal impact while providing valuable information to optimize their treatment and medication. The single-use concept can also reduce time spent in the hospital as it allows patients to be sent home earlier while still remotely monitoring their vital signs.
Even more versatile than its predecessors, the new patch now also measures blood oxygen saturation (SpO2). This is an important vital sign for assessing a patient's physical health as low blood oxygen levels can indicate hypoxemia which – if untreated – can compromise organ functions and can even lead to respiratory or cardiac arrest. It also includes an accelerometer for tracking physical activity, an ECG heart activity tracker and bioelectrical impedance monitoring.
"Traditionally, blood oxygen saturation is measured with a separate device attached to the finger. This is not very practical for daily living, so we developed a new technique that performs the measurement with a chest patch, via reflective photoplethysmography. By adding this sensing capability to our wearable solution, we are now able to measure three essential vital signs - heart rate, breathing rate and blood oxygen saturation - with a single unobtrusive and comfortable chest patch," explains Bernard Grundlehner.