Both the iPhone app store and the Android market have their fair share of heart rate monitors, which use either the microphone or in some cases the camera to detect your heart rate, with varying levels of accuracy. A researcher from Worcester Polytechnic Institute wanted to take this idea a little further and has developed a smartphone app that measures not only heart rate, but also heart rhythm, respiration rate and blood oxygen saturation using the phone’s built-in video camera.
The app analyzes video clips recorded while the patient’s fingertip is pressed against the lens of the camera. Just like a standard clinical pulse oximeter, it then captures small changes in light reflected by the pulsing blood in the capillaries, and translates these changes to the actual vital signs by using some of the same algorithms employed in professional devices.
For testing purposes, the researchers used the app on a Motorola Droid phone with a group of volunteers and compared the readings with those from standard clinical monitoring devices. According to these tests, the smart phone monitor was as accurate as the traditional devices. If this app indeed works as well as advertised, this could become a powerful diagnostic tool which is readily available to both doctors and patients anywhere they are.
The next challenge the researchers are working on is accurate detection of atrial fibrillation from the heart rhythm signal. They are working on an app for that, and have started a preliminary clinical study. Details of the current app are described in a paper published online in the journal IEEE Transactions on Biomedical Engineering.
Press release: Hold the Phone for Vital Signs…