Non-Invasive Continuous Blood Pressure Sensors in Biomedical Engineering Research: A Review

In this work, non-invasive continuous blood pressure sensors in a recent decade have been reviewed to motivate the development of health monitoring devices for future biomedical engineering applications. Firstly, the fundamentals in blood pressure measurement of arterial pulse wave analysis and pulse transit time (PTT) techniques are explained as the basis blood pressure demodulation. Secondly, a brief history of blood pressure instrumentation is provided which reveals the significant interest in this instrumentation. A validation protocol for non-invasive blood pressure instruments is, thirdly, summarized as a guideline for future innovation. This work, consequently, describes the principles and utilizations of electrocardiographic (ECG) electrodes, electronic sensors, fiber optic sensors, photoplethysmographic (PPG) sensors, and ultrasound systems in blood pressure measurement. Ultimately, the advantages, limitations, and prospects of each sensor are discussed which would eventually pave ways to the development of novel blood pressure measuring instruments for future practical applications.