Researchers at Worcester Polytechnic Institute (WPI) have developed a smart phone application that can measure respiration rate, blood oxygen saturation, heart rate, and heart rhythm using the phone’s built-in video camera. According to the researchers, the app yields vital signs as accurate as standard medical monitors now in clinical use.

Details of this new technology appear in the journal IEEE Transactions on Biomedical Engineering.

“This gives a patient the ability to carry an accurate physiological monitor anywhere, without additional hardware beyond what’s already included in many consumer mobile phones,” the authors write. “One of the advantages of mobile phone monitoring is that it allows patients to make baseline measurements at any time, building a database that could allow for improved detection of disease states.”

The application analyzes video clips recorded while the patient’s fingertip is pressed against the lens of the phone’s camera. As the camera’s light penetrates the skin, it reflects off pulsing blood in the finger; the application is able to correlate subtle shifts in the color of the reflected light with changes in the patient’s vital signs.

To test the accuracy, volunteers were monitored using standard monitoring devices currently in clinical use for measuring respiration, pulse rate, heart rhythm, and blood oxygen content, while simultaneously pressing a finger onto the camera of a Motorola Droid phone. While all the devices were recording, the volunteers went through a series of breathing exercises while their vital signs were captured. Subsequent analysis of the data showed that the smart phone monitor was as accurate as the traditional devices.

According to the researchers, while this study was done on a Droid, the technology is easily adaptable to most smart phones with an embedded video camera. The research team is currently at work developing a version of the mobile monitoring technology for use on video-equipped tablets like the iPad.

The smart phone application, now in the final development and clinical testing phase, is not yet available for the public.

Source. Worcester Polytechnic Institute