Feb 11, 2009This article was originally published by RFID Update.
February 11, 2009—Researchers are using real-time location system (RTLS) technology to try to improve early detection of dementia and the safety for patients afflicted by it. Patients with advanced cases of dementia often see two-dimensional objects in three dimensions, and are prone to wander. Researchers at the University of South Florida (USF) have outfitted dementia patients at two assisted living facilities with RTLS wristbands to collect data on their movements. The researchers will use the data to see how movement patterns correlate to dementia, and how patients react to 2D visual cues.
"To a person with dementia, a black floor mat may appear as a hole, so the person won't cross it. An assisted living facility may put down a mat to deter patients from exiting an area. There is also a pattern of wallpaper that makes a door appear as a bookcase, so a dementia patient won't attempt to leave through the door," Dr. Bill Kearns, an assistant professor and researcher at USF told RFID Update. "Our problem was how to estimate the relative contributions of these two techniques, compared to an alarm or other system. RTLS was brought in as a new microscope to study the problem."
Kearns and his team have installed ultra-wideband (UWB) RTLS readers at two assisted living facilities that use visual cues like the mats and special wallpaper. The readers cover a common area at each facility, and a total of 75 residents wear wristwatch-style RTLS tags. The RTLS system provides data about how often doorways, corridors and other locations were approached, and how many times residents attempted to exit. The data is analyzed to measure the effectiveness of the visual cues used to deter exits.
Patient movement data is also analyzed to see if patterns change over time. Kearns found there is a correlation between movement patterns and the loss of cognitive function. He is hopeful that the research can lead to earlier detection of dementia. As dementia advances the risk of falling increases, so monitoring the progression of the disease is important for patient safety.
USF and the facilities plan to keep the RTLS systems in place indefinitely. So far approximately 2.4 million movement records have been collected. The study may expand to see if movement data is a predictor of falls, Kearns said.
He selected ultra-wideband RTLS technology primarily because of its accuracy. The system, from Ubisense, is accurate to within about 10 inches, which is acceptable for purposes of the research. The system covers approximately 250 square meters at each facility. About a dozen patients use wheelchairs or walkers, which have not caused interference. Kearns said there have been no reading problems and the systems are very reliable. They have been running since last March and he has yet to replace a battery in an RTLS tag.
"We needed the systems to be as maintenance-free as possible," Kearns said. "They are running in real, working assisted living facilities."
Many hospitals and nursing homes use wireless wristbands and ID badges to monitor patient locations and trigger alarms if wandering or abduction is suspected. The assisted living facilities working with USF haven't incorporated the RTLS system into their own patient monitoring operations, but are considering doing so, according to Kearns. RTLS is even more widely used in healthcare facilities for asset and equipment tracking, and adoption continues to grow (see RTLS Goes Mainstream with New Ekahau Deal).
