Search results for "photoplethysmography"
showing 10 items of 53 documents
Photoplethysmography in dogs and cats: a selection of alternative measurement sites for a pet monitor.
2018
Objective Photoplethysmography (PPG) is an increasingly popular health and well-being tool for monitoring heart rate and oxygen saturation. Due to the pigmentation and hairiness of dogs and cats, a pulse oximeter is routinely placed solely on the tongue. As this approach is feasible only for pet monitor use during surgical procedures, we investigate PPG signal quality on several other measurement sites that would be better tolerated by conscious animals. Approach Acquired PPG signals are analyzed by four signal quality indices: mean baseline, signal power, kurtosis, and tolerance score. Main results In dogs, the metacarpus and tail can be substituted for oral pulse oximeter placement since …
Observation of ventilation-induced Spo(2) oscillations in pigs: first step to noninvasive detection of cyclic recruitment of atelectasis?
2010
High arterial partial oxygen pressure (Pao(2)) oscillations within the respiratory cycle were described recently in experimental acute lung injury. This phenomenon has been related to cyclic recruitment of atelectasis and varying pulmonary shunt fractions. Noninvasive detection of Spo(2) (oxygen saturation measured by pulse oximetry) as an indicator of cyclic collapse of atelectasis, instead of recording Pao(2) oscillations, could be of clinical interest in critical care. Spo(2) oscillations were recorded continuously in three different cases of lung damage to demonstrate the technical feasibility of this approach. To deduce Pao(2) from Spo(2), a mathematical model of the hemoglobin dissoci…
Multispectral, Fluorescent and Photoplethysmographic Imaging for Remote Skin Assessment
2017
Optical tissue imaging has several advantages over the routine clinical imaging methods, including non-invasiveness (does not change the structure of tissues), remote operation (avoids infection) and ability to quantify the tissue condition by means of specific image parameters. Dermatologists and other skin experts need compact (preferably pocket-size), self-sustained and easy-to-use imaging devices. The operational principles and designs of ten portable in-vivo skin imaging prototypes developed at the Biophotonics Laboratory of Institute of Atomic Physics and Spectroscopy, University of Latvia during the recent five years are presented in this paper. Four groups of imaging devices are con…
Wearable Multisensor Ring-Shaped Probe for Assessing Stress and Blood Oxygenation: Design and Preliminary Measurements
2023
The increasing interest in innovative solutions for health and physiological monitoring has recently fostered the development of smaller biomedical devices. These devices are capable of recording an increasingly large number of biosignals simultaneously, while maximizing the user’s comfort. In this study, we have designed and realized a novel wearable multisensor ring-shaped probe that enables synchronous, real-time acquisition of photoplethysmographic (PPG) and galvanic skin response (GSR) signals. The device integrates both the PPG and GSR sensors onto a single probe that can be easily placed on the finger, thereby minimizing the device footprint and overall size. The system enables the e…
Wearable PPG Sensor Matrix for Cardiovascular Assessment
2014
Wearable biomonitoring systems and smart textiles for healthcare are gaining more importance and significance in the R&D sphere due to their potentials in healthcare and sports. Such biomonitoring systems offer a number of advantages in comparison to the conventional equipment proving mobility of the wearer during a long-term monitoring of vital parameters. There are different options to set up the physiological monitoring using wireless and wearable technologies. One of the scenarios is addressing textiles as a carrier of electronics. Moreover, those differ by their functional applications, registered physiological parameters and technology solutions. Still, the most demanded biomonitoring…
Reliability of Short-Term Heart Rate Variability Indexes Assessed through Photoplethysmography
2018
The gold standard method to monitor heart rate variability (HRV) comprises measuring the time series of interbeat interval durations from electrocardiographic (ECG) recordings. However, due to the widespread use, simplicity and usability of photoplethysmographic (PPG) techniques, monitoring pulse rate variability (PRV) from pulse wave recordings has become a viable alternative to standard HRV analysis. The present study investigates the accuracy of PRV, measured as a surrogate of HRV, for the quantification of descriptive indexes computed in the time domain (mean, variance), frequency domain (low-to-high frequency power ratio LF/HF, HF band central frequency) and information domain (entropy…
Validity of the Wrist-Worn Polar Vantage V2 to Measure Heart Rate and Heart Rate Variability at Rest
2021
Heart rate (HR) and heart rate variability (HRV) can be monitored with wearable devices throughout the day. Resting HRV in particular, reflecting cardiac parasympathetic activity, has been proposed to be a useful marker in the monitoring of health and recovery from training. This study examined the validity of the wrist-based photoplethysmography (PPG) method to measure HR and HRV at rest. Recreationally endurance-trained participants recorded pulse-to-pulse (PP) and RR intervals simultaneously with a PPG-based watch and reference heart rate sensor (HRS) at a laboratory in a supine position (n = 39; 5-min recording) and at home during sleep (n = 29; 4-h recording). In addition, analyses wer…
Toward the development of a remote photoplethysmographic sensor
2019
Heart-rate estimation performed with remote photoplethysmography is a very active research field. Since pioneer works in 2010, which demonstrated the feasibility of the measure with low-grade consumers’ camera (webcam), the number of scientific publications have increased significantly in the domain. Hence, we observe a multiplication of the methods in order to retrieve the photoplethysmographic signal which hasled to an increased precision and quality of the heartrate estimation. Region of interest segmentation is a key step of the processing pipeline in order to maximize the quality of the measured signal. We propose a new method to perform remote photoplethysmographic measurement using a…
Optimal Source Selection for Image Photoplethysmography
2016
International audience; This paper presents an optimal selection on the region of interest (ROI) and color spaces to extract photoplethysmography signals from facial videos. The study is carried out under two sections; ROI selection and color space selection. We compared five different ROI selection for different regions of the face. We also investigated three color spectrums namely additive, perceptual and orthogonal color spaces. The study experimented on the publicly available human-computer interaction (HCI) database. When evaluated on 30 subjects, the results showed that the ROI selection on the forehead and the green spectrum of the additive color space to provides higher accuracy for…
Mutes gļotādas mikrocirkulācijas novērtējums izmantojot attēlvides fotopletizmogrāfiju
2019
Manipulācijas ar smaganām ir kļuvušas par standarta procedūrām zobārstniecībā rosinot nepieciešamību pēc smaganu funkcionālām izvērtēšanas metodēm. It īpaši tādēļ, ka smaganu klīniskā aina nevienmēr atspoguļo to funkcionālo stāvokli un morfoloģiskās īpatnības var nomaskēt funkcionālos traucējumus. Vietējā anestēzija ir neatņemama zobārstniecības procedūra, kas novērš pacienta diskomfortu manipulāciju laikā, taču dažreiz tā var radīt arī nevēlamās blakusparādības vai pat komplikācijas, kam ir vairāki iemesli (lielās devas, individuālā jutība uz kādu no anestēzijas komponentu, traucējumi pulpas un smaganu asins apgādē, vai pat neirotoksicitāte). Līdz ar to devas samazināšana ir ļoti svarīga, …