July 25, 2022 — As scientists work on wearable technology that promises to revolutionize healthcare, researchers from the University of Texas at Austin and Texas A&M University report a big win in pursuit of a target very popular: a non-invasive solution for continuous treatment. arterial pressure home monitoring.
Not only that, but this development comes in the surprising form of a temporary tattoo. That’s right: just like the kind kids like to wear.
Thin, sticker-like wearable electronic tattoos can provide continuous and accurate blood pressure monitoring, researchers report in their new study.
“Thanks to this new technology, we will have the opportunity to understand how our blood pressure fluctuates during the day. We will be able to quantify the impact of stress on us,” says Roozbeh Jafari, PhD, professor of biomedical engineering, electrical engineering and computer science at Texas A&M and co-author of the study.
Reveal the entire image, not just the dots
Home blood pressure monitors have been around for many years now. They work just like the blood pressure monitors doctors use in their office: you place your arm in a cuff, press a button, feel pressure on your arm, and get a reading.
While the results of this method are accurate, they are also just a moment in time. Our blood pressure can vary dramatically throughout the day, especially in people with labile hypertension, where blood pressure fluctuates from extreme to extreme. So looking at point readings is a bit like focusing on a few dots inside a pointillist painting – you might miss the big picture.
Physicians may also find ongoing monitoring helpful in getting rid of false readings from “white coat syndrome.” Basically, this means that a person’s blood pressure rises due to anxiety about being in a doctor’s office, but it’s not true hypertension.
Bottom Line: The ability to monitor a person’s blood pressure continuously for hours or even days can provide clearer and more accurate information about a person’s health.
How do health monitoring tattoos work?
Electronic tattoos for health monitoring are not completely new. John A. Rogers, Ph.D., from Northwestern University first proposed the idea of surveillance through temporary tattoos 12 years ago. Some concepts, such as UV Watch Tattoos, had already been adopted by scientists and brought to market. But existing models were not suitable for monitoring blood pressure, according to Deji Akinwande, PhDprofessor of electrical and computer engineering at the University of Texas at Austin and another co-author of the study.
“[UV monitoring tattoos] are very thick,” he says. “They create too much movement when used to measure blood pressure because they slip.”
So the Texas-based research team worked to develop a slimmer, more stable option.
“The key ingredient in e-tattoos is graphene,” says Akinwande.
Graphene is carbon similar to what’s inside your graphite pencil. The material is conductive, which means it can conduct small electrical currents through the skin. For blood pressure monitoring, graphene promotes bioelectrical impedance analysis (BIA), which resembles the technology used in smart scales that measure body fat.
With electronic tattoos, the thin layers of graphene stick to the skin and do not slip, eliminating “artifacts” or bad data. Graphene e-tattoos can be worn on the skin for about a week – or about as long as children’s temporary tattoos to like.
After the graphene captures the raw data, a machine learning algorithm interprets the information and provides the results in the units used to measure blood pressure: millimeters of mercury (mmHg), commonly referred to as blood pressure “points”.
How accurate are the results? The tests measured blood pressure within the limits of 0.2 ± 5.8 mmHg (systolic), 0.2 ± 4.5 mmHg (diastolic), and 0.1 ± 5.3 mmHg (mean arterial pressure). In other words: if this were a basketball player shooting hoops, the vast majority of shots would be whistles and occasionally a few would hit the rim. This means good accuracy.
When will the E-Tattoos be available?
The Jafari and Akinwande teams are working on a second generation of their e-tattoo which they expect to be available within the next 5 years.
The upgrade they envision will be smaller and compatible with smartwatches and phones that use Bluetooth technology and Near Field Communication (NFC) to transfer data and give them power. With these updates, e-tattoos for continuous blood pressure monitoring will be ready for clinical testsand consumer use soon after.
“Anyone can benefit from knowing their blood pressure records,” says Akinwande. “It’s not just for people at risk for hypertension, but for others to proactively monitor their health, stress and other factors.”