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Your smartphone’s getting even smarter

When the pandemic hit, I’m sure I wasn’t alone in making sure I knew where the thermometer was, replacing the battery on the pulse oximeter, and checking the expiration dates on the cold medicine in the cabinet. Your home “doctor’s bag” may well have a blood pressure monitor in it: a device with an inflatable arm cuff attached to it. Once the cuff’s inflated and deflation begins, your diastolic and systolic pressure are measured on the way down.

Since the cuff technique for measuring BP was devised more than 120 years ago, this technology has been pretty much the only non-invasive way to measure blood pressure.

Now a Swiss-based company, Leman Micro Devices, has come up with a cuff-less solution. Rather than measure an upper-arm artery, Leman’s e-Checkup with V-Sensor gauges BP – with clinical accuracy – through the fingertip. It also measures other vital signs: temperature, blood oxygen, heart rate and respiration rate. And it works on your smartphone. Talk about a “doctor’s bag”.

There are three parts to LMD’s health sensing solution: the V-Sensor hardware module, eCheckup software for gathering and analyzing data, and the server where data are stored and where diagnostic information is offered.

The V-Sensor has a pressure sensor embedded in a soft, flat epoxy resin that is pressed against the fingertip. LEDs and a photodiode form a conventional pulse oximeter that illuminates the tip of the finger. A thermopile measures heat radiation to estimate body temperature. The application-specific integrated circuit designed by LMD controls the LEDs; captures and digitizes data from the photodiode, pressure sensor, and thermopile; and communicates with the mobile phone processor. (Source: article by Maurizio di Paolo Emilio on embedded.com)

To take your blood pressure, you just hold your phone, putting your index finger on the V-Sensor, which is pretty tiny: only 15 mm long and resides on the smartphone’s back, and your thumb on the front screen. The e-Checkup app lets you know whether you’re getting too much pressure or not enough. After less than a minute, the reading is taken. No worrying about whether you’ve got the cuff in the right place.

And there’s even more:

LMD’s research and development have shown that V-Sensor data can be combined with accelerometer data in the phone when held against the chest to find the timing of the heart function: left ventricular expulsion time (LVET), aortic and mitral valve timing, and many others. Further measurements may combine images from the phone’s camera.

All this is well beyond what’s possible with other wearables and health apps, and promises to be a real breakthrough. When people can monitor their vitals so easily, without having to acquire and learn to use all sorts of separate devices, they’ll be able to keep much better track of their health. As will their physicians. Right now, we’re seeing more and more use of telehealth, through which many routine appointments are handled over the phone or via conferencing software. The ability to remotely provide such a wealth of health information through a simple smartphone application is going to greatly improve the quality of virtual medicine.

Bottom line: another great technological approach to making real improvements to life.

Now if only they can come up with a way to determine whether someone has COVID-19, or has survived a bout with it and built-up antibodies.