Review of photoplethysmography based non-invasive continuous blood pressure methods

Blood pressure is an important parameter for early detections of cardiovascular diseases. There have been many relevant technological advances to measure blood pressure, such as in wearable sensing, pervasive computing, and smartphones. The disadvantage of conventional measurement is discomfort for the patients because of painful cuff inflation. The emergence of photoplethysmography for blood pressure estimation is offering a more convenient method. Photoplethysmography can generally be grouped into the following three categories; pulse wave velocity, pulse transit time, and pulse wave analysis. The objective of this review is to study the achievement of photoplethysmography based non-invasive continuous blood pressure methods. The method is quite promising and useful for the future studies and enhancement on cuff-less continuous BP monitoring approach.