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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Estudo comparativo entre dois métodos de calibração da pletismografia respiratória por indutância em individuos saudáveis / Comparative study between two methods of calibration of respiratory inductive plethysmography

Barbosa, Renata Cleia Claudino 13 June 2011 (has links)
Nas últimas décadas, considerável atenção foi direcionada para os dispositivos de mensuração não invasiva da configuração e coordenação toracoabdominal. Dentre os dispositivos mais empregados, destaca-se aquele que emprega a Pletismografia Respiratória por Indutância (PRI) que, apesar de ser considerado um dispositivo de avaliação reprodutível e acurado, apresenta divergências acerca do método de calibração para estimativa da participação dos compartimentos torácico e abdominal, principalmente quando utilizada em diferentes posturas corporais. O padrão-ouro da calibração da PRI é o método de calibração por isovolume (ISOCAL). Entretanto, a grande maioria dos estudos emprega somente a calibração qualitativa diagnóstica (QDC) devido ao fato desta não necessitar manobras respiratórias específicas. Em vista disso, o objetivo deste estudo foi comparar os dois métodos de calibração da PRI, em 3 diferentes posturas (decúbito dorsal, sedestação e ortostatismo). Foram avaliados 28 indivíduos saudáveis (18 mulheres/10 homens), com idade de 25,4±3,9 anos (média±DP). Todos os indivíduos foram submetidos aos dois métodos de calibração (ISOCAL e QDC) e avaliados nas 03 posturas. Foi verificado que os valores da constante de proporcionalidade dos sinais elétricos dos compartimentos (K) foram distintos em ambos os métodos de calibração nas 3 posturas avaliadas. Os valores de K avaliados com a calibração ISOCAL e QDC foram, respectivamente, 1,6±0,5 vs. 2,0±1,2 em decúbito dorsal, 2,5±0,8 vs. 0,6±0,3 em sedestação, e 2,0±0,8 vs. 0,6±0,3 em ortostatismo (p<0,05 para todas as comparações). Os nossos resultados sugerem que a QDC não deve ser considerada um método acurado para a calibração da PRI. Além disso, os valores da constante K do ISOCAL mostram ainda que a calibração do equipamento deve ocorrer para cada postura avaliada / In recent decades, considerable attention has been directed to devices for noninvasive measurement of thoracoabdominal configuration and coordination. Among the most commonly applied devices, there is one that employs the respiratory inductive plethysmography (PRI), which, despite being considered a device for reproducible and accurate assessment, shows variations on the calibration method to estimate the contribution of the thoracic and abdominal compartments especially when applied in different body postures. The gold standard in the calibration of PRI is the method of isovolume calibration (ISOCAL). However, most studies employ only the qualitative diagnostic calibration (QDC) due to the fact that this does not require specific respiratory maneuvers. This study aims to compare the two methods of calibration of the PRI in three different postures (supine, standing, and seated). A total of 28 healthy subjects (18 men mulheres/10), aged 25.4 ± 3.9 years (mean ± SD). All subjects underwent both methods of calibration (QDC and ISOCAL) and assessed at the 03 postures. It was found that the values of the constant of proportionality of the electrical signals of compartments (K) were different in both calibration methods evaluated in three postures. The values of K evaluated with calibration ISOCAL and QDC were respectively 1.6 ± 0.5 vs. 2.0 ± 1.2 supine position, 2.5 ± 0.8 vs. 0.6 ± 0.3 in seated position, and 2.0 ± 0.8 vs. 0.6 ± 0.3 in standing position (p <0.05 for all comparisons). Our results suggest that the QDC should not be considered an accurate method for calibration of the PRI. Moreover, the values of constant K ISOCAL also show that the calibration of equipment should occur for each position evaluated
2

Are Respiratory Behaviors Affected in Individuals With Adductor Spasmodic Dysphonia?

Biedess, Katie 01 June 2006 (has links)
Adductor spasmodic dysphonia (ADSD) is a focal dystonia that is characterized by voice breaks due to involuntary contractions of the adductor muscles of the vocal folds. These spasms can interfere with the coordination and balance of the respiratory and phonatory systems interfering with normal voice production. Disruptions in normal respiratory behaviors are well documented in inviduals with laryngeal disorders, including ADSD. Previous research regarding respiratory processes in ADSD has focused on airflow and pressure; however, there are many other parameters that have not been considered and may shed new light on the respiratory behaviors of individuals with ADSD. Therefore, the current pilot study attempted to determine if individuals with ADSD differed from controls in various breathing parameters while engaged in conversational and reading tasks.Thirty individuals were tested; fifteen in the ADSD group and fifteen in the age- and gender-matched control group. Respitrace, an inductive plethysmography device, calculated 14 different respiratory measures related to volume, timing, thoracic displacement and respiratory efficiency. The results of the study indicated that various significant differences existed between groups. Those with ADSD were found to have statistically higher ventilation rates, a greater frequency of breaths per minute, a higher degree of muscular inefficiency/breathlessness and labored breathing. These results indicated that individuals with ADSD suffered from disordered breathing due to the neurologically related obstruction at the level of the larynx. Differences according to task were also found. Specifically, the rib cage contributed to a lesser extent in voice production and the participants utilized longer inspiratory times, exhaled a larger volume of air and took longer to reach peak expiratory flow during conversational tasks when compared to reading tasks. These differences were attributed to a higher cognitive-linguistic demand required during conversational speech. Overall, the results of this study have many clinical implications. Most importantly, these findings support the idea that individuals with ADSD may experience difficulties with respiration as the effects of their Botox injection begin to wear off. Further research is needed with regards to the effects laryngeal spasms have on other respiratory behaviors.
3

Estudo comparativo entre dois métodos de calibração da pletismografia respiratória por indutância em individuos saudáveis / Comparative study between two methods of calibration of respiratory inductive plethysmography

Renata Cleia Claudino Barbosa 13 June 2011 (has links)
Nas últimas décadas, considerável atenção foi direcionada para os dispositivos de mensuração não invasiva da configuração e coordenação toracoabdominal. Dentre os dispositivos mais empregados, destaca-se aquele que emprega a Pletismografia Respiratória por Indutância (PRI) que, apesar de ser considerado um dispositivo de avaliação reprodutível e acurado, apresenta divergências acerca do método de calibração para estimativa da participação dos compartimentos torácico e abdominal, principalmente quando utilizada em diferentes posturas corporais. O padrão-ouro da calibração da PRI é o método de calibração por isovolume (ISOCAL). Entretanto, a grande maioria dos estudos emprega somente a calibração qualitativa diagnóstica (QDC) devido ao fato desta não necessitar manobras respiratórias específicas. Em vista disso, o objetivo deste estudo foi comparar os dois métodos de calibração da PRI, em 3 diferentes posturas (decúbito dorsal, sedestação e ortostatismo). Foram avaliados 28 indivíduos saudáveis (18 mulheres/10 homens), com idade de 25,4±3,9 anos (média±DP). Todos os indivíduos foram submetidos aos dois métodos de calibração (ISOCAL e QDC) e avaliados nas 03 posturas. Foi verificado que os valores da constante de proporcionalidade dos sinais elétricos dos compartimentos (K) foram distintos em ambos os métodos de calibração nas 3 posturas avaliadas. Os valores de K avaliados com a calibração ISOCAL e QDC foram, respectivamente, 1,6±0,5 vs. 2,0±1,2 em decúbito dorsal, 2,5±0,8 vs. 0,6±0,3 em sedestação, e 2,0±0,8 vs. 0,6±0,3 em ortostatismo (p<0,05 para todas as comparações). Os nossos resultados sugerem que a QDC não deve ser considerada um método acurado para a calibração da PRI. Além disso, os valores da constante K do ISOCAL mostram ainda que a calibração do equipamento deve ocorrer para cada postura avaliada / In recent decades, considerable attention has been directed to devices for noninvasive measurement of thoracoabdominal configuration and coordination. Among the most commonly applied devices, there is one that employs the respiratory inductive plethysmography (PRI), which, despite being considered a device for reproducible and accurate assessment, shows variations on the calibration method to estimate the contribution of the thoracic and abdominal compartments especially when applied in different body postures. The gold standard in the calibration of PRI is the method of isovolume calibration (ISOCAL). However, most studies employ only the qualitative diagnostic calibration (QDC) due to the fact that this does not require specific respiratory maneuvers. This study aims to compare the two methods of calibration of the PRI in three different postures (supine, standing, and seated). A total of 28 healthy subjects (18 men mulheres/10), aged 25.4 ± 3.9 years (mean ± SD). All subjects underwent both methods of calibration (QDC and ISOCAL) and assessed at the 03 postures. It was found that the values of the constant of proportionality of the electrical signals of compartments (K) were different in both calibration methods evaluated in three postures. The values of K evaluated with calibration ISOCAL and QDC were respectively 1.6 ± 0.5 vs. 2.0 ± 1.2 supine position, 2.5 ± 0.8 vs. 0.6 ± 0.3 in seated position, and 2.0 ± 0.8 vs. 0.6 ± 0.3 in standing position (p <0.05 for all comparisons). Our results suggest that the QDC should not be considered an accurate method for calibration of the PRI. Moreover, the values of constant K ISOCAL also show that the calibration of equipment should occur for each position evaluated
4

Adaptations respiratoires et locomotrices des sujets obèses lors du test de marche de six minutes / Respiratory and locomotor adaptations of obese subjects during 6 minute walk test

Retory, Yann 25 January 2017 (has links)
La méthode de référence pour l’évaluation de la capacité d’exercice est l’Exploration Fonctionnelle d’eXercice (EFX). En pratique, pour des problèmes de coût, de matériel et d’expertise médicale, l’EFX n’est pas réalisée chez tous les sujets dont la capacité d’exercice mérite d’être explorée. Le test de marche de 6 minutes (6MWT) ne présente pas ces inconvénients mais ne donne pas d’informations sur les adaptations physiologiques au cours de cet exercice. L’objectif de ce travail de thèse était de concevoir une méthode non invasive de monitorage des adaptations ventilatoires et locomotrices. L’accent a été porté sur le respect du caractère spontané de ces adaptations. La pléthysmographie respiratoire d’inductance (RIP) et l’accélérométrie ont été choisies pour l’évaluation de ces adaptations. Les performances de ces nouvelles méthodes de monitorage sont acceptables pour ces deux dimensions. La confrontation de notre méthode RIP au pneumotachographe, outil de référence, objective des coefficients de corrélations compris entre 0,81 et 0,96 pour le volume courant(Vt), les temps inspiratoires (Ti) et expiratoires (Te). De même, la confrontation de notre méthode accélérométrique avec le contrôle vidéographique montre des coefficients de corrélations de 0,99 pour les paramètres locomoteurs : cadence, longueur moyenne du pas et détermination automatique des distances parcourues (6MWD). La comparaison des profils ventilatoires et locomoteurs entre contrôles et sujets obèses révèle qu’une discrimination est possible (p<0,01 pour Vt, Ti, Te et p<0 ,001 pour cadence, longueur moyenne de pas et 6MWD). Ainsi, même une population sans pathologie respiratoire comme la population obèse sans comorbidités, choisie comme modèle d’étude dans ce travail, peut être discriminée par notre méthode de monitorage. Ces résultats sont encourageants au regard de l’amélioration de la prise en charge des sujets obèses et laissent entrevoir des perspectives tant au niveau technologique qu’à un niveau clinique plus large pour, par exemple, les sujets atteints de pathologies respiratoires susceptibles de limiter leur capacité d’effort. / The reference method for assessment of exercise capacity is the cardio-pulmonary exercise testing (CPET). Nevertheless, CPET is expensive, time consuming, requires specifics skills and is not used for all subjects needing exercise capacity assessment. The 6 minute walk test (6MWT) is free of these disadvantages but does not give basic information about physiological adaptation induced by walking. The aim of this study was to design a non-invasive method for ventilatory and locomotor monitoring. Respect of the spontaneous aspects of these adaptations was considered. Respiratory inductive plethysmography (RIP) was considered for ventilatory evaluation whereas locomotor adaptation was assessed with a tri-axial accelerometer. These new methods provided acceptable results for ventilatory and locomotor dimensions. Confronting our new RIP method with a pneumotachograph as a reference device, we found correlation coefficients from. 0.81 to 0.96 for determination of tidal volume (Vt), inspiratory (Ti) and expiratory time (Te). Confronting our accelerometric method with video recordings as control, we found significant correlation coefficients (r=0.99 and p< 0.001) for determination of cadence, mean step length and automatic distance covered (6MWD) during the 6MWT. Comparisons of ventilatory and locomotor pattern of control and obese without comorbidities showed that discriminating their pattern was possible (p<0.01 for Vt, Ti, Te and p<0.001 for cadence, mean step length and 6MWD). These results imply that even a population without respiratory disorders as the obese population considered in this study, can be discriminated with our monitoring method. It can be concluded that this method is promising for improvement of care to obese subjects and raises technological and clinical perspectives for subjects with respiratory disorders
5

Mesure non invasive de suivi des transferts de fluides liés aux activités cardiorespiratoires chez le rat : vers une «bague aortique virtuelle» / Non-invasive measurement of fluids exchanges induced by cardiorespiratory activity on the small animal : toward a "virtual aortic flowprobe"

Flenet, Timothé 03 February 2017 (has links)
Il est avéré que les signaux de pléthysmographie par inductance comportent des composantes cardiaques et respiratoires pouvant présenter un intérêt pour un suivi physiologique. Cette technique est largement utilisée chez l’homme et chez les mammifères de taille moyenne, mais n’a jamais été mise en œuvre chez les petits rongeurs de laboratoire comme le rat. Cette thèse vise à apporter la preuve analytique et expérimentale (TRL3) d’une application cardiaque de la pléthysmographie cardiorespiratoire par inductance (PCRI) fondée sur le concept amont de « bague aortique virtuelle » (BAOV). La BAOV permet de mettre en œuvre une mesure externe des débits aortiques « instantanés » à l’aide de la PCRI en lieu et place d’un instrument positionné autour du vaisseau lui-même.La thèse a débuté par une phase de spécification et de conception guidée par l’interdépendance entre la physiologie et les contraintes instrumentales. Les performances métrologiques à atteindre sont dictées par un saut d’échelle entre l’homme et le rat. Le développement d’une chaine de mesure optimisée a permis de repousser les limites des systèmes existants en rendant possible la mesure de variations de volumes de quelques microlitres. En parallèle, l’identification de critères de validation, de méthodes de référence et la mise au point de protocoles expérimentaux ont conduit à la définition d’une stratégie de validation de l’instrument de mesure développé et du concept de BAOV.À l’issue de ces trois années, un système de PCRI à ultra-haute résolution a été mis au point. Après calibration, l’exactitude sur les mesures de variations de section est de 5 % sur un banc de test micrométrique. L’interchangeabilité de la mesure des variations de volume du thorax sur la gamme physiologique a été évaluée par rapport à une mesure pneumotachographique sur 9 animaux anesthésiés. Les limites d’agrément obtenues sont inférieures à 20 %. L’induction d’un challenge hémodynamique sur 11 animaux anesthésiés dont le débit aortique est mesuré en parallèle avec la PCRI et une bague de débit ultrasonique placée au niveau sous-diaphragmatique démontre l’équivalence entre les deux systèmes. Par ailleurs, la grande similitude entre les signaux de débits des deux méthodes valide le concept de bague aortique virtuelle proposé / It is recognized that inductive plethysmographic signals contain cardiac and respiratory components, which can be of interest for physiological monitoring. This technology is widely used in humans and medium mammals, but it has never been implemented in small laboratory rodents. This PhD aims to provide the analytic and experimental proof (TRL3) of a cardiac application of the cardio-respiratory inductive plethysmography (CRIP), based on the upstream concept of an “virtual aortic probe” (VAP). The VAP allows to realize an extern measure of “instantaneous” aortic flows thanks to CRIP instead of an instrument located directly around the vessel.The PhD starts with a phase of specification and conception driven by the interdependency between physiology and instrumental constraints. The expected metrological performances are established by a scale jumping between man and rat. The development of an optimized acquisition line has enabled to stretch the limits of existing systems; it allows to measure volume variations of a few microliters. At the same time, validation criteria and reference methods have been identified and experimental protocols have been specified in order to define the validation strategy of the developed instrument and VAP concept.At the end of these 3 years, an ultra-high resolution CRIP system has been developed. After calibration, the accuracy on the section variation measurements is 5% on a micrometric test-bench. The interchangeability of the thorax volume variation measure on a physiological range has been evaluated by comparison with a pneumotachographic measure on 9 anesthetized animals and the limits of agreement are lower than 20%. A hemodynamic challenge has been induced on 11 anesthetized animals, and the aortic flow has been simultaneously measured by CRIP and with an ultrasonic flow probe at under diaphragm level. This demonstrates the equivalence between both systems. And the high similarity between flow signals from both methods validates the proposed concept of virtual aortic probe

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