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Estimating heart rate variability using facial video photoplethysmography: a pilot validation study

Video photoplethysmography (vPPG) uses a digital camera to detect pulsations in the blood vessels of the skin, which can be used to estimate various physiological parameters. The aim of this study was to investigate the accuracy and precision of heart rate variability (HRV) indices estimated using a smartphone came...

Comparative Assessment of PPG Signal Quality Across Fingers for Wearable Health Monitoring and Implications for Sensor Design Optimization

In clinical settings, every minute of delay in treating a cardiopulmonary emergency can reduce a patient's chance of survival by up to 10%. Photoplethysmography (PPG) is a low-cost, noninvasive method widely adopted in both clinical, and consumer settings to monitor cardiopulmonary signals. Therefore, clinical PPG puls...

Session Wise Estimation of Aortic Pulse Wave Velocity Using Ring Photoplethysmography During Sleep

Multi-Site Photoplethysmography Features Under Heart Rate and Stroke Volume Variations: An In Silico Study

Assessing respiratory rates and signs of air hunger using the PneumoRator sensor.

Objectives: To investigate whether the PneumoRator wearable sensor could accurately assess Respiratory Rate (RR) and signs of air hunger (SAH) compared with clinician-observed assessment in adults with and without breathing pattern disorder (BrPD). Design: A pilot cross-sectional observational study. Setting: A researc...

Effect of altitude on respiratory oscillometry in healthy adults

Respiratory oscillometry is a sensitive, non-invasive pulmonary function test that does not require forced breathing maneuvers. Although the density of the inspired gas is known to influence the measurement, its effect within the same subject at different altitudes has been little explored. We investigated whether geog...