Generally, if a doctor wants to know a patient's blood pressure, they have to place a cuff around the person's arm and inflate it. Not only can this be uncomfortable for the patient, but it also only indicates what their blood pressure is at the time that the test is performed. That's why scientists at Australia's Monash University are developing an alternative – a cuffless blood pressure estimation system that is worn for hours at a time, wirelessly transmitting real-time readings.

First of all, this is isn't the only no-cuff system in existence. According to lead scientist Mehmet Yuce, however, it does have a key advantage.

"Existing technologies use an optical pulse wave or photoplethsmographic sensor at the radial artery or fingertip to measure the pulse wave to estimate blood pressure," he tells us. "We use radar technology […] It is easier and more comfortable for the human body because it does not present any pressure to the body."

The system incorporates a few small sensors that are worn against the skin at arterial sites, beneath the clothing. By measuring the amount of time that it takes pulsed blood to travel between those sensors, it's possible to ascertain the patient's "pulse wave velocity" and thus accurately estimate their blood pressure.

Yuce and his team are now working on converting the lab-based prototype to a compact internet-connected setup, and hope to begin commercialization soon. "The goal is to be able to provide monitoring for a continuous 24-hour period, and to be able to send that information to a doctor in real time," he says.

A paper on the technology was recently presented at the 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, in Milan.