Washington DC , May 3
Scientists at the University of Waterloo have developed a radar that can wirelessly monitor the vital signs of patients thus eliminating the dependency on machines.
The research was published in the journal IEEE Access.
Housed in a device smaller than a cellphone, the new technology records heart and breathing rates using sensitive radar waves that are analysed by sophisticated algorithms embedded in an onboard digital signal processing unit.
Researchers developed the system to monitor sleep apnea patients by detecting subtle chest movements instead of connecting them to equipment in labs via numerous cumbersome wires.
"We take the whole complex process and make it completely wireless. And instead of a clinic, it could be done in the comfort of your own bed and run daily for continuous monitoring," said George Shaker, a cross-appointed professor of electrical and computer engineering at Waterloo.
In a study at the Research Institute for Aging, the radar unit was mounted to the ceiling over the bed of more than 50 volunteers as they slept normally in a model long-term care apartment.
The system, which collects and analyses data from radar waves that are reflected back to the unit from the bodies of patients, achieved results over 90 per cent as accurate as standard hard-wired equipment.
"This is the first time radar has been used for heart sensing with this degree of accuracy and in such an uncontrolled environment. Our subjects slept unobstructed, in any position, for up to eight hours," said Mostafa Alizadeh, who led the study.
Researchers are also exploring the use of the technology to monitor activity levels and falls by residents of long-term care homes, and in hospitals for routine monitoring of heart and breathing rates of all kinds of patients.
Advantages of the system for apnea monitoring include complete privacy since no cameras are used, much-improved comfort and potential use in homes rather than special sleep clinics.
"With traditional systems involving wires and appointments booked weeks in advance, you can't sleep as you normally do in your own bed at home, making the common sleep study an unpleasant experience," said Shaker.
In addition to sleep apnea, which involves breathing that repeatedly stops and starts, the system can monitor conditions such as periodic limb movement disorder, restless leg syndrome and seizures.