Search results for "Plethysmograph"
showing 10 items of 94 documents
Low-invasive multisensor real-time acquisition system for the assessment of cardiorespiratory and skin conductance parameters
2022
In recent years, the attention to the health and comfort of the individual, together with the electronic miniaturization progress, have led to an increased interest in the development of biomedical devices that are able to acquire a multitude of biomedical signals. Such devices should be wearable and comfortable during daily use, to be thus suitable for continuously monitoring psychophysical health states. In this context, we have designed and realized a portable biomedical device capable of real-time acquisition of electrocardiographic (ECG), photoplethysmographic (PPG), breathing and galvanic skin response (GSR) signals, for a noninvasive monitoring of multiple physiological parameters. T…
Measurements of cardiac Pre-Ejection period using a combo PPG-ECG system
2015
The extraction of biomedical parameters, for early disease detection, is assuming today an ever increasing and fundamental importance. In particular, in the cardiologic field, the preejection period (PEP) is the duration of the iso-volumetric left ventricle contraction until the aortic valve opening. This parameter is a non-constant additive delay, which rapidly changes in response to stress, emotion and physical effort. To estimate this period, several wearable electronics devices have been developed in literature, and among them the Impedance Cardiogram equipment is the most used. However, these systems are often expensive and bulky. In this paper, we propose a cost-effective and easy to …
Blood Pressure Monitoring with a PPG Embedded System
2014
Semi-blind Source Extraction Methods: Application to the measurement of non-contact physiological signs
2018
Non-contact physiological measurements are highlydesirable in many biomedical fields such asdiagnosis of infants, geriartic patients, patients withextreme physical trauma, and fitness and well-being.Remote photoplethysmography is increasingly beingused for non-contact measurement of heart rate fromvideos which is one of the most common biomedicalproperty required for most medical diagnosis. Oneof the common techniques for performing remotephotoplethysmography involves using Blind SourceSeparation (BSS) methods to extract the cardiacsignal from video data.In this context, the objective of this thesis is todevelop different methods in the field of extractionand separation of sources by improv…
Estimating Heart Rate, Energy Expenditure, and Physical Performance With a Wrist Photoplethysmographic Device During Running
2017
BackgroundWearable sensors enable long-term monitoring of health and wellbeing indicators. An objective evaluation of sensors’ accuracy is important, especially for their use in health care. ObjectiveThe aim of this study was to use a wrist-worn optical heart rate (OHR) device to estimate heart rate (HR), energy expenditure (EE), and maximal oxygen intake capacity (VO2Max) during running and to evaluate the accuracy of the estimated parameters (HR, EE, and VO2Max) against golden reference methods. MethodsA total of 24 healthy volunteers, of whom 11 were female, with a mean age of 36.2 years (SD 8.2 years) participated in a submaximal self-paced outdoor running test and maximal voluntary exe…
Ticlopidine in the Treatment of Multiple Atherosclerotic Arteriopathy: a Strain Gauge Plethysmography and Döppler Spectrum Analysis Evaluation
1987
The effect of ticlopidine was compared with flunarizine in patients with iliac–femoral and / or femoral–popliteal arteriosclerotic arteriopathy accompanied by lesions of the cervical arteries of no haemodynamic significance. In the lower limbs, plethysmography (strain gauge measurements) and Döppler ultrasonography integrated by spectral analysis of the cervical arteries showed qualitative and quantitative improvements of the regional haematic flow. Side-effects were negligible which suggests that ticlopidine is useful in the treatment of multiple arteriosclerotic arteriopathy.
Activation of Astrocytes in the Persistence of Post-hypoxic Respiratory Augmentation
2021
Acute hypoxia increases ventilation. After cessation of hypoxia loading, ventilation decreases but remains above the pre-exposure baseline level for a time. However, the mechanism of this post-hypoxic persistent respiratory augmentation (PHRA), which is a short-term potentiation of breathing, has not been elucidated. We aimed to test the hypothesis that astrocytes are involved in PHRA. To this end, we investigated hypoxic ventilatory responses by whole-body plethysmography in unanesthetized adult mice. The animals breathed room air, hypoxic gas mixture (7% O2, 93% N2) for 2min, and again room air for 10min before and after i.p. administration of low (100mg/kg) and high (300mg/kg) doses of a…
2019
Background Endothelial dysfunction is a consequence of type 2 diabetes mellitus, but it is unclear whether endothelial dysfunction of conductance versus resistance vessels may also precede type 2 diabetes mellitus development. Methods and Results In a population‐based cohort of 15 010 individuals from the GHS (Gutenberg Health Study) (aged 35–74 years at enrollment in 2007–2012), we identified 1610 cases of incident pre–diabetes mellitus and 386 cases of incident type 2 diabetes mellitus by hemoglobin A 1c (HbA 1c ) and/or medical history between 2012 and 2017. Endothelial function of conductance and resistance vessels was measured by flow‐mediated dilation and digital volume plethysmograp…
A silicon photomultiplier-based analog front-end for DC component rejection and pulse wave recording in photoplethysmographic applications
2022
The growing attention towards healthcare and the constant technological innovations in the field of semiconductor components have allowed a widespread availability of smaller devices, suitable to be worn and able to continuously acquire physiological signals. Wearable devices are, however, more prone to yield signals corrupted by artifacts caused by movement. This issue is particularly relevant in photoplethysmographic (PPG) applications where also, to exploit the whole dynamic range of the acquisition device, the DC component of the signal should be removed and the AC component amplified. In this context, we have designed and realized an analog front-end (AFE) suitable to be integrated wit…
Venozās sistēmas izmaiņas pacientiem, kuri ārstēti ar jaunu inovatīvu metodi endovaskulārai GARU femorālo artēriju slēgumu ārstēšanai: PQ BYPASS
2020
PQ Bypass ir jauna un inovatīva metode pilnībā endovaskulārai femoropopliteālai šuntēšanai. Patlaban pasaulē ir pētījumi par PQ Bypass metodes, kur aprakstīta tās rezultāti arteriālajai sistēmai, bet nav atrodami pētījumi par PQ Bypass metodes ietekmi uz venozo sistēmu. Pētījuma mērķis ir izvērtēt PQ Bypass metodes ilgtermiņa ietekmi uz apakšējo ekstremitāšu venozo sistēmu. Materiāli un metodes: Prospektīvais pētījums tika veikts PSKUS Asinsvadu ķirurģijas centrā. Pētījumā tika analizēti 50 pacientu, kam ir C un D tipa bojājumi femoropopliteālajā segmentā pēc TASC II klasifikācijas, venozās sistēmas izmaiņas ilgtermiņā pēc PQ Bypass operācijas. Statistiskajām analīzēm tika izmantotas progra…