Cuffless blood pressure monitoring using hydrostatic pressure changes.

This paper presents a new principle for noninvasive blood pressure measurements through a modified volume-oscillometric technique that eliminates an inflatable pressure cuff, and instead takes advantage of natural hydrostatic pressure changes caused by raising and lowering the subject's arm. This new methodology provides the distinct advantage of using an absolute gauge pressure reference for measurements, and does not necessarily require additional actuation.

Utility of the photoplethysmogram in circulatory monitoring.

The photoplethysmogram is a noninvasive circulatory signal related to the pulsatile volume of blood in tissue and is displayed by many pulse oximeters and bedside monitors, along with the computed arterial oxygen saturation. The photoplethysmogram is similar in appearance to an arterial blood pressure waveform. Because the former is noninvasive and nearly ubiquitous in hospitals whereas the latter requires invasive measurement, the extraction of circulatory information from the photoplethysmogram has been a popular subject of contemporary research.

Adaptive hydrostatic blood pressure calibration: development of a wearable, autonomous pulse wave velocity blood pressure monitor.

A technique for calibrating non-invasive peripheral arterial sensor signals to peripheral arterial blood pressure (BP) is proposed. The adaptive system identification method utilizes a measurable intra-arterial hydrostatic pressure change in the sensor outfitted appendage to identify the transduction dynamics relating the peripheral arterial blood pressure and the measured arterial sensor signal. The proposed algorithm allows identification of the calibration dynamics despite unknown physiologic fluctuations in arterial pressure during the calibration period under certain prescribed conditions.

A finite element analysis of local oscillometric blood pressure measurements.

Traditional circumferential oscillometric blood pressure measurements are based on a complex interplay between the perturbed underlying artery and the surrounding tissue. When there is a balance in pressures acting across the arterial wall, the pulsation amplitude is expected to be a maximum. The purpose of this study was to examine the change in pulsation amplitude for a given pressure resulting from a focally applied compression.

Wearable, cuff-less PPG-based blood pressure monitor with novel height sensor.

A truly wearable non-invasive blood pressure (NIBP) sensor--light-weight, compact, unobstrusive, and essentially unnoticeable to the patient--could revolutionize healthcare delivered beyond the traditional walls of medical facilities, offering new ways to care for patients in their everyday surroundings. This paper presents results from our work towards the development of a self-contained, wearable blood pressure sensor. A PPG-based approach to blood pressure monitoring is presented.