VTT is increasing its focus on printed electronics in healthcare !
Printed electronics proposes a way of manufacturing wearable and disposable medical IoT devices that can measure patients and transmit vital healthcare data to the IoT. Within several years, these devices can potentially monitor all patients around the clock and improve patient safety in hospitals. Teemu Alajoki, Senior Scientist at VTT, speaks with RFID & Wireless IoT Global about the applications and perspectives for printed electronics in the healthcare industry today.
Expertise since 2001
VTT, the Technical Research Centre of Finland Ltd, started working on printed electronics in 2001. Today, over 100 scientists and engineers are deployed on printed electronics projects at VTT. “VTT was an early player when it comes to printed electronics. The current project for printed electronics in healthcare is building on earlier experiences. Over the years, medical applications have emerged as a focus market for printed electronics,” Senior Scientist Teemu Alajoki explains.
Medical applications are a focus market
For Teemu Alajoki, the immediate applications of printed electronics in healthcare can be found in the hospital: “Wearable and disposable electronics can be used to realize wireless sensors that can measure basic physiological parameters such as body temperature, respiratory rate, and heartrate. They can also be used for more complex measurements such as pulse oximetry, electrocardiography, and electroencephalography.”
Today, continuous patient monitoring is carried out only in high acuity settings like in operating room or in intensive care unit where patient is connected to bedside monitor with bulky cables.
“The wireless connection allows integrating the sensor into the hospital‘s Wide Area Network. Wearables provide around-the-clock monitoring, allowing doctors to react directly to emergencies not only in high acuity units but also in ward - but also at the same time allowing patients to walk freely in the ward and to even take showers. In comparison to traditional, bulky monitoring systems or once-per-day manual checks, printed electronics with an IoT connection can provide real-time monitoring for all hospital patients,” the VTT researcher says.
Detect heart events, sepsis, and more
Wearables and disposables can be used to monitor patients before, during, and after surgery. By providing around-the-clock readings on patients, they can greatly improve patient safety.
“Undetected problems account for thousands of sudden deaths in the ward globally. Having access to real-time data can help doctors prioritize risk patients in emergency settings, as well as provide improved after-care. Medical sensors can reveal infections, sepsis, and inflammations after surgery. They can also detect cardiac events, allowing doctors to predict and prevent heart attacks”, Teemu Alajoki reports. “Patient safety can be increased. Patients could even be sent home earlier while still being monitored remotely, saving cost in an ageing society.”
At-home cloud-based treatment becomes possible
Sending patients home while continuing monitoring of their vitals for a time opens the door for remote medicine. Products for at-home patients could support doctors in providing better care for their patients even outside of regularly scheduled visits.
The scientist outlines a possible scenario: “With BLE or NFC sensor wearables, patients can tap their smartphone to the tag. The patients either take their own measurement or the healthcare data goes directly to the doctor, who analyses it and calls the patients in, if necessary. This could lead to cloud-based, preventive healthcare. An important aspect in the big picture is the automatic data analytics of the sensor data using artificial intelligence. Automatic data analysis becomes critical because doctors do not have the time to analyse the increased amount of data. At VTT, other teams are already working on such advanced healthcare data systems.”
Comfort is a must
The form factor favoured by the VTT scientists is a conformable patch that sticks to the patient‘s skin. VTT designs all layers, from the adhesives via electrodes and wiring to components and lamination. One of the key challenges is patient comfort, Teemu Alajoki reports:
“Printed electronics is well-suited for plasters, but the conventionally used plastic substrates such as PET are not the best choice in terms of wearability. This is why we are printing on thermoplastic polyurethane, which is softer material and also more flexible and stretchable. We also use special adhesives that are powerful enough to stick for several days, but do not irritate the skin. Comfort is crucially important for medical electronics. When you put the plaster on your skin, you should be able to forget it‘s even there.”
Shielding against defibrillation pulses
For the medical sector, electromagnetic compatibility of all devices has to be assured in order to guarantee patient safety. “Electromagnetic interference is a complex topic. Each hospital is different, and extensive tests are needed in order to confirm compatibility,” Teemu Alajoki reports.
“In addition, dielectric shielding of printed electronics components is a must in a hospital environment for the most sensitive measurements, such as ECG. Sensors and electronics connected to the skin have to withstand defibrillation pulses. VTT is already making strides in order to fully accommodate this important medical standard and recently proved that defibrillation-proof resistors can be realized with printed electronics.”
Hybrid of printed and discrete components
Today, not all components necessary for a medical IoT sensor can be printed reel-toreel. Wiring, electrodes, contacts, and passive components such as resistors can be realized using printed electronics. However, the design requires, for instance, an external battery. The project leader explains why:
“High-end medical devices such as these require a lot of power because they are continuously transmitting data. Current use cases for disposable single-use sensors call for a product life of two to three days. Printed batteries will be possible at some point in the future, but for now VTT pursues a hybrid approach: the design still relies on some discrete, conventional electronics components. Right now, printed electronics especially shine for wiring and electrodes because of their flexibility and ease of manufacturing. As more components can be printed, they will be integrated into the devices.”
Strong partner network reduces time-to-market
In order to design, develop, produce, and field test printed electronics for healthcare, VTT is working closely with partners such as GE Healthcare and University Hospitals worldwide, Teemu Alajoki explains:
“Healthcare development is relatively expensive because of the high quality standards and regulations that each design needs to fulfil even before the first prototype is brought into a hospital. This is why it is important to possess a doorway to the market as well as a doorway to the end user. New products need to reach a high level of maturity and safety before coming into contact with patients. If they are successfully tested, then they can be brought to market.”