Design Implementation and Evaluation of a Mobile Continuous Blood Oxygen Saturation Monitoring System

In this study, we built a mobile continuous Blood Oxygen Saturation (SpO2) monitor, and for the first time, explored key design principles towards daily applications.

We firstly built a customized wearable computer that can sense two-channel photoplethysmogram (PPG) signals, and transmit the signals wirelessly to smartphone. Afterwards, we explored many SpO2 model building principles, focusing on linear/nonlinear models, different PPG parameter calculation methods, and different finger types. Moreover, we further compared PPG sensor placement principles by comparing different hand configurations and different finger configurations. Finally, a dataset collected from eleven human subjects was used to evaluate the mobile health monitor and explore all of the above design principles.

The experimental results show that the root mean square error of the SpO2 estimation is only 1.8, indicating the effectiveness of the system.

These results indicate the effectiveness of the customized mobile SpO2 monitor and the selected design principles.

This research is expected to facilitate the continuous SpO2 monitoring of patients with clinical indications.