The term outpatient may just be on the verge of being redefined by a team of Canadian researchers who developed a radar-based system for wirelessly monitoring patients' vital signs.

Remotely measuring vital signs of patients is nothing new, however, to do so, the patient or health care professionals have to stop whatever they're doing and attach and set up the sensors and wires, or other apparatus, which can be time-consuming. There has been increasing interest in the use of radars particularly in health monitoring but their performance has never been studied nor tested and reported.

In an article published in the IEEE Journal, a group of engineers from the University of Waterloo in Canada conducted a study at the University's Research Institute for Aging, wherein they mounted a radar unit to the ceiling over the beds of volunteers. Their initial aim was for the system to detect and monitor sleep apnea patients by detecting very subtle chest movements. They posited that instead of using wearable and contact devices, this remote sensing system will be unobtrusive to patients' activities of daily living since it can penetrate clothing items.

The device which is as small as a mobile phone recorded heartbeats and respiration rates which the use of sensitive radar waves that are analyzed by algorithms embedded in an onboard digital signal processing unit. The results of the study show that compared to standard hard-wired equipment, the system showed over 90 percent as accurate.

"This is the first time radar has been used for heart sensing with this degree of accuracy and in such an uncontrolled environment," said Mostafa Alizadeh, a research associate who led the study. "Our subjects slept unobstructed, in any position, for up to eight hours."

Currently, besides breathing irregularities such as sleep apnea, the system can also monitor seizures, restless leg syndrome, and periodic limb movement disorders. At this time, the team is also exploring the use of this 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.

Given the accuracy and convenience of the said technology, with further studies and testing, it would eventually be a common installation not only in several types of health care settings but also in homes, schools and other workplaces, which would be very beneficial in providing absolute health care and reducing healthcare costs.