Evaluation of measurement site for monitoring orthostatic pulse rate change

Measuring orthostatic heart rate (HR) change has been used as one of the screening methods for elder care or elderly rehabilitation because it enables to evaluate autonomic nervous function. In this study, we developed a forehead photo-plethysmogram (PPG) measurement device that had five sets of green-light PPG sensors in order to acquire orthostatic pulse rate (PR) change. In the experiment, 10 young healthy subjects were recruited to participate and asked to wear the elderly person experience kit for elderly simulation. 5 forehead PPGs, 4 wrist PPGs and ECG were measured simultaneously. The accuracy of PRs was evaluated by error rates calculated by PRs from each site. As a result, it was confirmed that PRs estimated from PPG in the center of forehead with low contact sensor pressure had high accuracy.