One of the most crucial markers of heart health is blood pressure, but it's challenging to measure it regularly and accurately outside of a hospital environment. The industry standard for many years has been cuff-based devices that tighten around the arm to provide a reading. But now, scientists at Texas A&M University and The University of Texas at Austin have created an electronic tattoo that can be comfortably worn on the wrist for hours while providing continuous blood pressure measurements with an accuracy level that surpasses nearly all options currently on the market.
According to Deji Akinwande, a professor in the Department of Electrical and Computer Engineering at UT Austin and one of the project's co-leaders, "Blood pressure is the most important vital sign you can measure, but the methods to do it outside of the clinic passively, without a cuff, are very limited." The project's findings were published in a new paper on June 20, 2022, in Nature Nanotechnology.
If high blood pressure is not addressed, it might result in significant cardiac issues. Because a standard blood pressure check only measures one specific point in time, or one data point, it might be challenging to monitor.
Roozbeh Jafari, a professor of biomedical engineering, computer science, and electrical engineering at Texas A&M and the other co-leader of the study, stated that taking occasional blood pressure measures has several drawbacks and does not give insight into precisely how our body is operating.
Blood pressure readings are made possible by the e-continuous tattoo's monitoring system in a variety of circumstances, including times of high stress, when sleeping, working out, etc. More measures can be delivered by this gadget than any other up to this point.
Due mostly to technologies like smartwatches, mobile health monitoring has advanced significantly in recent years. These gadgets make use of metallic sensors that collect data from LED light sources that are shone through the skin.
Leading smartwatches, however, are not yet capable of measuring blood pressure. This is due to the difficulty in providing precise readings caused by the timepieces' tendency to slide about on the wrist and potential distance from arteries. Additionally, measurements based on light might be inaccurate in those with darker skin tones or broader wrists.
One of the strongest and thinnest substances in use, graphene is a crucial component of the e-tattoo. Although the atoms are neatly organized into tiny layers, it is comparable to the graphite found in pencils. Because the sensors are enclosed in a sticky, stretchy material that is comfortable to wear for extended periods of time and does not slide about, e-tattoos make sense as a platform for mobile blood pressure monitoring.
"The tattoo's sensor is subtle and weightless. You set it down there. It doesn't even move, and you can't even see it, according to Jafari. "You need the sensor to remain in the same location because if you move it around, the measurements will change."
By injecting an electrical current into the skin and evaluating the body's reaction, or bioimpedance, the gadget makes measurements. A relationship exists between bioimpedance and variations in blood pressure that are related to variations in blood volume. The researchers had to develop a machine learning model to examine the link since the association is not especially clear in order to obtain correct blood pressure measurements.
Cuff-less blood pressure monitoring is the "holy grail" of medicine, according to Jafari, but there isn't a workable option available just yet.
It is a part of a bigger effort in medicine to utilize technology to free patients from mechanical dependence while gathering more data wherever they are, enabling them to move between rooms and clinics while still receiving individualized treatment.
All of this information, according to Akinwande, "may help develop a digital twin to model the human body and forecast and demonstrate how it can react and respond to therapies over time."
Refer to "Continuous cuffless monitoring of arterial blood pressure by graphene bioimpedance tattoos," published in Nature Nanotechnology on June 20, 2022, by Dmitry Kireev, Kaan Sel, Bassem Ibrahim, Neelotpala Kumar, Ali Akbari, Roozbeh Jafari, and Deji Akinwande.
