WIB: Real-time, Non-intrusive Blood Pressure Detection Using Smartphones

Blood pressure (BP) is an essential vital sign related to many severe diseases, such as heart failure, kidney failure. Frequent BP detection can provide doctors more information to treat the disease. However, conventional at-home BP detection devices require completely blocking blood flow, which can lead to discomfort and disruption of normal activity when users want to perform frequent assessments. So a convenient solution should reduce the trouble of detecting BP in the daily life. In this work, we have designed and evaluated a smartphone-based BP detection application named WIB. WIB utilizes the smartphone's acoustic sensors to obtain the chest motion caused by the heart beating and the smartphone's camera to capture the pulse at the fingertip. We have recruited 30 volunteers who come from the author's institution, to carry out comprehensive evaluations ofWIB. We perform BP perturbation experiments to obtain different blood pressure data from these volunteers. The experiment results show that the average of Pearson correlation coefficient across all volunteers of the blood pressure estimation is 0.42-0.74 (alpha = 0.6, sigma = 0.12), the average of RMSE across all volunteers is 4.2-8.8 mmHg (alpha = 5.8, sigma = 1.8).