The approach is based on comparing the full PPG waveform between two points along the artery rather than measuring the time-of-flight. It has been demonstrated that an accurate and repeatable blood pressure measurement can be obtained by measuring the phase change (e.g., phase velocity), amplitude change, and distortion of the PPG waveforms along the brachial artery. There has been documentation of relative success, but a device that is able to provide the required accuracy and repeatability has not yet been developed. A number of researchers have used pulse wave velocity (PWV) of blood in the arteries to infer the beat-to-beat blood pressure. It can be used to monitor the effect of prolonged exposures to reduced gravitational environments and the effectiveness of various countermeasures. This wearable physiological monitor can be used to continuously observe the beat-to-beat blood pressure (B3P). Real-time compliance estimate is used to refine both the mean arterial and pulse pressures to provide the beat-to-beat blood pressure measurement. The phase analysis is used primarily for the computation of the mean arterial pressure, while the waveform analysis is used primarily to obtain the pulse pressure. Phase and waveform analyses are performed on filtered proximal and distal photoplethysmographic (PPG) waveforms obtained from the brachial artery. This device provides non-invasive beat-to-beat blood pressure measurements and can be worn over the upper arm for prolonged durations. The digitized PPG signals are used as inputs into the beat-to-beat blood Photoplethysmography, which measures changes in arterial blood volume, is commonly used to obtain heart rate and blood oxygen saturation. This allows signal processing of waveforms to determine the phase and amplitude changes. Minimizing the measurement separation and confining the measurement area to a single, well-defined artery allows the waveform to retain the general shape between the two measurement points.
0 kommentar(er)
