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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.
331

Mechanical simulation of the endovascular repair of abdominal aortic aneurysms

Roy, David 11 1900 (has links)
Ce travail de thèse porte sur la simulation du déploiement des prothèses vasculaires de type stent-graft (SG) lors de la réparation endovasculaire (EVAR) des anévrismes de l’aorte abdominale (AAA). Cette étude se présente en trois parties: (i) tests mécaniques en flexion et compression de SG couramment utilisés (corps et jambage de marque Cook) ainsi que la simulation numérique desdits tests, (ii) développement d’un modèle numérique d’anévrisme, (iii) stratégie de simulation du déploiement des SG. La méthode numérique employée est celle des éléments finis. Dans un premier temps, une vérification du modèle éléments finis (MEF) des SG est realisée par comparaison des différents cas de charge avec leur pendant expérimental. Ensuite, le MEF vasculaire (AAA) est lui aussi vérifié lors d’une comparaison des niveaux de contraintes maximales principales dans la paroi avec des valeurs de la littérature. Enfin, le déploiement est abordé tout en intégrant les cathéters. Les tests mécaniques menés sur les SG ont été simulés avec une différence maximale de 5,93%, tout en tenant compte de la pré-charge des stents. Le MEF de la structure vasculaire a montré des contraintes maximales principales éloignées de 4,41% par rapport à un modèle similaire précédemment publié. Quant à la simulation du déploiement, un jeu complet de SG a pu être déployé avec un bon contrôle de la position relative et globale, dans un AAA spécifique pré-déformé, sans toutefois inclure de thrombus intra-luminal (TIL). La paroi du AAA a été modélisée avec une loi de comportement isotropique hyperélastique. Étant donné que la différence maximale tolérée en milieu clinique entre réalité et simulation est de 5%, notre approche semble acceptable et pourrait donner suite à de futurs développements. Cela dit, le petit nombre de SG testés justifie pleinement une vaste campagne de tests mécaniques et simulations supplémentaires à des fins de validation. / This thesis work is concerned with the simulation of the deployment of stent-graft (SG) vascular prostheses in abdominal aortic aneurysms (AAA) during endovascular repair (EVAR). This study is composed of three main parts: (i) mechanical tests in bending and compression of frequently used SG (body and leg from Cook) as well as the numerical simulation of these tests, (ii) development of a numerical AAA model, (iii) strategy of simulation of SG deployment. The finite element method is used. In a first step, a verification of the finite element model (FEM) of SG is performed by comparison of the different load cases with their experimental counterparts. Subsequently, the vascular FEM is also verified in terms of maximal principal constraints in the wall against values available in the literature. Finally, the deployment is investigated while taking the catheters into account. The mechanical tests performed on the SG were simulated with a maximal difference of 5.93%, while accounting for the pre-load in stents. The FEM of the vascular structure showed maximal principal stresses that were 4.41% far from the ones found in the literature for a similar model. Regarding the simulation of SG deployment, a complete set of SG could be deployed with a good control of the relative and global position into a specific and pre-deformed AAA, however, no intra-luminal thrombus (ILT) was included. The AAA wall was modeled with an isotropic hyperelastic constitutive law. In the clinical setting, the maximum tolerated difference between reality and simulation is 5%, therefore, our approach seems acceptable, and could give rise to further developments. However, the small amount of tested SG justifies a wide campaign of additional mechanical tests and simulations for the sake of validation.
332

Coarctation of the aorta : register and imaging studies

Rinnström, Daniel January 2016 (has links)
Background Coarctation of the aorta (CoA) constitutes 5-8 % of all congenital heart disease (CHD) and is associated with long-term complications such as hypertension (HTN) and left ventricular hypertrophy (LVH). Factors associated with HTN, LVH, and diffuse myocardial fibrosis, are not yet fully explored in this population. Methods Papers I-III: The Swedish national register of congenital heart disease (SWEDCON) was used to identify adult patients with repaired CoA. Paper IV: Data on 2,424 adult patients with CHD was extracted from SWEDCON and compared to controls (n = 4,605) regarding height, weight and body mass index (BMI). Paper V: Adults with CoA (n = 21, age 28.5 (19.1-65.1) years, 33.3 % female) referred for CMR were investigated with T1 mapping to determine left ventricular extracellular volume fraction (ECV). Results Papers I-II: Out of 653 patients, 344 (52.7 %) had HTN. In a multivariable model, age (years) (OR 1.07, CI 1.05-1.10), sex (male) (OR 3.35, CI 1.98-5.68) and BMI (kg/m2) (OR 1.09, CI 1.03-1.16) were associated with having HTN, and so was systolic arm-leg blood pressure (BP) gradient where an association was found at the ranges (10, 20] mmHg (OR 3.58, CI 1.70-7.55) and > 20 mmHg (OR 11.38, CI 4.03-32.11), in comparison to the range [0, 10] mmHg. When investigating 243 patients with diagnosed HTN, 127 (52.3 %) had elevated BP (≥ 140/90 mmHg). Age (years) (OR 1.03, CI 1.01-1.06) was associated with elevated BP, and so was systolic arm-leg BP gradient in the ranges (10, 20] mmHg (OR 4.92, CI 1.76-13.79), and > 20 mmHg (OR 9.93, CI 2.99-33.02), in comparison to the reference interval [0, 10] mmHg. Patients with elevated BP had more classes of anti-hypertensive medication classes prescribed (1.9 vs 1.5, p = 0.003). Paper III: Out of 506 patients, 114 (22.5 %) were found to have LVH. Systolic BP (mmHg) (OR 1.02, CI 1.01-1.04), aortic valve disease, (OR 2.17, CI 1.33–3.53), age (years) (OR 1.03, CI 1.01–1.05), and HTN (OR 3.02, CI 1.81-5.02), were associated with LVH, while sex (female) (OR 0.41, CI 0.24-0.72) was negatively associated with LVH. Paper IV: There was no difference in height, weight, or BMI between patients with CoA (n = 414) and the reference population. Paper V: In the population of 21 patients, an increased left ventricular myocardial ECV was found in 6 cases (28.6 %). Of the patients with increased ECV, 5/6 (83.3 %) were female (p = 0.002). Patients with increased ECV did not otherwise differ from the rest of the study population. iv Conclusions In adults with repaired CoA, HTN and LVH were common, and many patients with HTN had elevated BP despite treatment. The potentially modifiable factors BMI and systolic arm-leg BP gradient were associated with HTN, and the gradient was also associated with elevated BP among patients with diagnosed HTN. The gradient’s significance remained even within what the current guidelines consider acceptable ranges. Potentially modifiable factors associated with LVH were systolic BP and aortic valve disease. We found no general difference in height, weight, or BMI between patients with CoA and the reference population. While LVH was more common among men, increased myocardial ECV was more common among women.
333

Nákladová analýza léčby výdutí břišní aorty ve Fakultní nemocnici Olomouc / Cost Analysis of Treatment of Abdominal Aortic Aneurysms in the Olomouc Hospital

Radmacher, Erich January 2011 (has links)
The aneurysma of abdominal aorta is a pathological amplification of the diameter of this artery. It is a serious illness which affects 2 -- 6 % men and 1 -- 2 % women over 60. In the case of a rupture there is the mortality of 80 -- 90 %. If the aneurysma is diagnosed in time it is necessary to solve this state with an adequate treatment. The surgical treatment consists in substitution of the afflected part with a vessel replacement. Thanks to the development of medicinal technologies the aorta aneurysma is more and more often treated by the help of stentgrapth by which the afflicted part of the aorta is set aside from the circulation. The theoretical (the first) part of this work deals with the issues of the aneurysma of abdominal aorta, and it also describes the methods of its treatment. Then the work describes costs analyses used in the medical service. The practical part of the work is dedicated to the cost analysis of the treatment by means of a cost minimalization method. The work processes data of a group of patients being treated during a certain period of time in the Olomouc University Hospital in the Department of Vessel Surgery and in the Department of Interventional Radiology. The aim of this work is to evaluate and compare objectively the costs of abdominal aorta aneurysma treatment by individual methods, and to compare the results with foreign studies.
334

Estiramento ou fluxo turbilhonar e baixa tensão de cisalhamento influem diferentemente no remodelamento aórtico em ratos / Stretch or turbulent flow and low wall shear stress differentially affect aorta remodeling in rats.

Prado, Cibele Maria 29 September 2006 (has links)
O presente estudo foi realizado para investigar a relação entre forças hemodinâmicas locais e remodelamento intimal e medial nos segmentos pré-estenose e pós-estenose da parede da aorta abdominal de ratos submetidos à estenose acentuada. Foram utilizados ratos Wistar machos divididos em dois grupos: sham-operado, grupo controle em que a aorta foi apenas manipulada, e grupo estenosado, animais submetidos à cirurgia de estenose da aorta abdominal. As aortas demonstraram duas respostas remodeladoras distintas e diferentes ao estímulo hemodinâmico induzido pela coarctação infra-diafragmática. A primeira é o remodelamento no segmento pré-estenótico hipertensivo com tensão circunferencial da parede aumentada associada com estresse tensional normal, fluxo laminar e tensão de cisalhamento normal. As células endoteliais eram heterogêneas, aumentadas em tamanho e alongadas em direção ao fluxo. Além disso, observou-se conspícuas placas neointimais difusamente distribuídas e espessamento medial. Nossos achados sugerem que a tensão circunferencial da parede aumentada devido a hipertensão tem papel fundamental no remodelamento desse segmento através de efeitos biomecânicos sobre o estresse oxidativo e expressão aumentada de TGF-?. A segunda é o remodelamento no segmento pós-estenótico normotenso com fluxo turbilhonar e baixa tensão de cisalhamento na parede associados a tensão circunferencial da parede e estresse tensional normais. As células endoteliais apresentavam-se semelhantes aos controles, exceto por alterações fenotípicas focais associadas à presença de conspícuas placas neointimais focalmente distribuídas, similares mas muito maiores que as encontradas no segmento pré-estenose. Mais estudos são necessários para se determinar como as forças mecânicas do fluxo turbilhonar e da baixa tensão de cisalhamento na parede são detectadas e traduzidas em sinais bioquímicos para as células e convertidas em alterações fenotípicas patofisiologicamente relevantes. / The present investigation was carried out to evaluate the relationship between local hemodynamic forces and intimal and medial remodeling in the proximal and distal segments of the arterial walls of rats in relation to severe stenosis of the aorta. Male Wistar young rats were divided randomly into: operated group, animals submitted to surgical abdominal aorta stenosis, and sham-operated group, a control group of animals submitted to sham operation to simulate abdominal aorta stenosis. Constricted aortas showed two distinct adaptive remodeling responses to hemodynamic stimuli induced by coarctation. The first is remodeling in the hypertensive prestenotic segment with increased circumferential wall tension associated with normal tensile stress, laminar flow/normal wall shear stress. The remodeling in this segment is characterized by enlarged heterogeneous endothelial cells, elongated in the direction of the blood flow, diffusely distributed neointimal plaques, appearing as discrete bulging toward the vascular lumen, and medial thickening. Our findings suggest that increased circumferential wall tension due to hypertension play a pivotal role in the remodeling of the prestenotic segment through biomechanical effects on oxidative stress and increased TGF-? expression. The second is remodeling in the normotensive poststenotic segment with turbulent flow/low wall shear stress and normal circumferential wall tension and tensile stress. The remodeling in this segment is characterized by groups of endothelial cells with phenotypic alterations and focally distributed neointimal plaques, similar but many of them larger than those found in the prestenotic segments. Further studies are needed to determine how the mechanical forces of turbulent flow/low shear stress are detected and transduced into biochemical signaling by the cells of the artery walls and then converted into pathophysiologic relevant phenotypic changes.
335

Avaliação das variáveis obtidas pela ultrassonografia com Doppler das grandes artérias abdominais e da femoral em gatos e cães submetidos à sedação.

Mello, Fabíola Peixoto da Silva January 2016 (has links)
Informações em tempo real da direção e tipo de fluxo sanguíneo podem ser obtidas com ultrassonografia com Doppler. Não foram encontrados dados na literatura de valores obtidos por este método da artéria celíaca e mesentérica cranial de gatos. Além disso, ocasionalmente há necessidade de sedar os gatos e cães para realização deste exame em quaisquer vasos em que se deseja obter mais informações. O trabalho possui dois objetivos. Um foi avaliar os aspectos quantitativos da onda espectral formada pelo fluxo sanguíneo das artérias: aorta, celíaca, mesentérica cranial, renal, ilíaca externa e femoral de gatos e cães hígidos; e compará-los aos obtidos dos mesmos animais submetidos à sedação, com um protocolo para cada espécie. Os gatos foram sedados com midazolam, cetamina e butorfanol, e os cães, com acepromazina e butorfanol. Outro objetivo foi obter valores velocimétricos de referência para artéria celíaca e artéria mesentérica cranial em gatos, através do Doppler espectral. Para isso, foram avaliados 20 gatos e 20 cães hígidos. Como resultado dos gatos, foram obtidos os valores de pico de velocidade sistólica, velocidade diastólica final, média da velocidade média, média da velocidade máxima, índice de resistividade e índice de pulsatilidade, tanto da artéria celíaca quanto da artéria mesentérica cranial de animais hígidos não sedados, e; foram obtidos esses mesmos dados das artérias aorta, renal, ilíaca externa e femoral e todos comparados entre os gatos sedados e não sedados, onde não foram encontradas diferenças estatisticamente significativas, exceto na velocidade diastólica final e velocidade média da artéria celíaca, e índice de resistividade e de pulsatilidade da artéria ilíaca. Já nos cães, observou-se que houve diferença de pelo menos dois dos parâmetros dopplervelocimétricos avaliados das artérias selecionadas, exceto da artéria femoral. Dessa forma, nos gatos foram fornecidos parâmetros dopplervelocimétricos da artéria celíaca e mesentérica cranial de animais não sedados, e conclui-se que, enquanto o protocolo utilizado nos gatos, com midazolam, cetamina e butorfanol, não alterou os valores encontrados nos vasos selecionados, exceto da artéria celíaca e da ilíaca; nos cães, o uso de acepromazina e butorfanol levou a modificação de parte desses valores em todos os vasos, exceto na artéria femoral. Assim, na realização deste exame com esses protocolos, essas diferenças devem ser consideradas. / Real time information about direction and type of blood flow can be obtained with Doppler ultrasound. No data was found in the literature regarding values of the celiac and cranial mesenteric artery in cats obtained through this method. Moreover, occasionally, for examining cats and dogs’ vessels about which we desire to get more information, there is a need to sedate these animals. This study has two objectives. One was to evaluate the quantitative aspects of spectral wave formed by the blood flow of aorta, celiac, cranial mesenteric, renal, external iliac and femoral arteries from healthy cats and dogs and compare them to the same animal under sedation, using one protocol for each species. The cats were sedated with midazolam, ketamine and butorphanol and the dogs with acepromazine and butorphanol. The second objective was to obtain velocimetric reference values from celiac and mesenteric cranial artery in cats. Twenty healthy cats and dogs were evaluated. As a result for the cats, values of peak systolic velocity, end diastolic velocity, time averaged mean velocity, time averaged maximum velocity, resistivity index and pulsatility index of both the celiac and the cranial mesenteric artery were obtained in healthy non-sedated animals, and; these same data from aorta, renal, external iliac and femoral were obtained, and all compared, between sedated and non-sedated cats, where statistically significant differences were not found, except in end diastolic velocity and average speed of the celiac artery, and resistance and pulsatility index of the iliac artery. In dogs, a difference was observed in at least two of the Doppler velocity parameters measured of the arteries, except for the femoral artery. Thus, Doppler velocity parameters of the celiac and cranial mesenteric artery in non-sedated cats were provided and it was concluded that the protocol used in cats, with midazolam, ketamina and buthorphanol did not alter the values of Doppler ultrasound in the selected vessels in cats, except celiac and external iliac artery. In addition, in dogs, the use of acepromazine and buthorphanol led to modification of part of these values in all vessels, except in the femoral artery. Thus, when carrying out this examination with these protocols, such differences should be considered.
336

Estiramento ou fluxo turbilhonar e baixa tensão de cisalhamento influem diferentemente no remodelamento aórtico em ratos / Stretch or turbulent flow and low wall shear stress differentially affect aorta remodeling in rats.

Cibele Maria Prado 29 September 2006 (has links)
O presente estudo foi realizado para investigar a relação entre forças hemodinâmicas locais e remodelamento intimal e medial nos segmentos pré-estenose e pós-estenose da parede da aorta abdominal de ratos submetidos à estenose acentuada. Foram utilizados ratos Wistar machos divididos em dois grupos: sham-operado, grupo controle em que a aorta foi apenas manipulada, e grupo estenosado, animais submetidos à cirurgia de estenose da aorta abdominal. As aortas demonstraram duas respostas remodeladoras distintas e diferentes ao estímulo hemodinâmico induzido pela coarctação infra-diafragmática. A primeira é o remodelamento no segmento pré-estenótico hipertensivo com tensão circunferencial da parede aumentada associada com estresse tensional normal, fluxo laminar e tensão de cisalhamento normal. As células endoteliais eram heterogêneas, aumentadas em tamanho e alongadas em direção ao fluxo. Além disso, observou-se conspícuas placas neointimais difusamente distribuídas e espessamento medial. Nossos achados sugerem que a tensão circunferencial da parede aumentada devido a hipertensão tem papel fundamental no remodelamento desse segmento através de efeitos biomecânicos sobre o estresse oxidativo e expressão aumentada de TGF-?. A segunda é o remodelamento no segmento pós-estenótico normotenso com fluxo turbilhonar e baixa tensão de cisalhamento na parede associados a tensão circunferencial da parede e estresse tensional normais. As células endoteliais apresentavam-se semelhantes aos controles, exceto por alterações fenotípicas focais associadas à presença de conspícuas placas neointimais focalmente distribuídas, similares mas muito maiores que as encontradas no segmento pré-estenose. Mais estudos são necessários para se determinar como as forças mecânicas do fluxo turbilhonar e da baixa tensão de cisalhamento na parede são detectadas e traduzidas em sinais bioquímicos para as células e convertidas em alterações fenotípicas patofisiologicamente relevantes. / The present investigation was carried out to evaluate the relationship between local hemodynamic forces and intimal and medial remodeling in the proximal and distal segments of the arterial walls of rats in relation to severe stenosis of the aorta. Male Wistar young rats were divided randomly into: operated group, animals submitted to surgical abdominal aorta stenosis, and sham-operated group, a control group of animals submitted to sham operation to simulate abdominal aorta stenosis. Constricted aortas showed two distinct adaptive remodeling responses to hemodynamic stimuli induced by coarctation. The first is remodeling in the hypertensive prestenotic segment with increased circumferential wall tension associated with normal tensile stress, laminar flow/normal wall shear stress. The remodeling in this segment is characterized by enlarged heterogeneous endothelial cells, elongated in the direction of the blood flow, diffusely distributed neointimal plaques, appearing as discrete bulging toward the vascular lumen, and medial thickening. Our findings suggest that increased circumferential wall tension due to hypertension play a pivotal role in the remodeling of the prestenotic segment through biomechanical effects on oxidative stress and increased TGF-? expression. The second is remodeling in the normotensive poststenotic segment with turbulent flow/low wall shear stress and normal circumferential wall tension and tensile stress. The remodeling in this segment is characterized by groups of endothelial cells with phenotypic alterations and focally distributed neointimal plaques, similar but many of them larger than those found in the prestenotic segments. Further studies are needed to determine how the mechanical forces of turbulent flow/low shear stress are detected and transduced into biochemical signaling by the cells of the artery walls and then converted into pathophysiologic relevant phenotypic changes.
337

Quantification of cardiovascular flow and motion : aspects of regional myocardial function and flow patterns in the aortic root and the aorta /

Kvitting, John-Peder Escobar, January 2004 (has links) (PDF)
Diss. Linköping : University, 2004.
338

Atherosclerosis of the ascending aorta as a risk factor for stroke after cardiac surgery : a study based on epiaortic ultrasound /

Bergman, Per, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
339

Avaliação das variáveis obtidas pela ultrassonografia com Doppler das grandes artérias abdominais e da femoral em gatos e cães submetidos à sedação.

Mello, Fabíola Peixoto da Silva January 2016 (has links)
Informações em tempo real da direção e tipo de fluxo sanguíneo podem ser obtidas com ultrassonografia com Doppler. Não foram encontrados dados na literatura de valores obtidos por este método da artéria celíaca e mesentérica cranial de gatos. Além disso, ocasionalmente há necessidade de sedar os gatos e cães para realização deste exame em quaisquer vasos em que se deseja obter mais informações. O trabalho possui dois objetivos. Um foi avaliar os aspectos quantitativos da onda espectral formada pelo fluxo sanguíneo das artérias: aorta, celíaca, mesentérica cranial, renal, ilíaca externa e femoral de gatos e cães hígidos; e compará-los aos obtidos dos mesmos animais submetidos à sedação, com um protocolo para cada espécie. Os gatos foram sedados com midazolam, cetamina e butorfanol, e os cães, com acepromazina e butorfanol. Outro objetivo foi obter valores velocimétricos de referência para artéria celíaca e artéria mesentérica cranial em gatos, através do Doppler espectral. Para isso, foram avaliados 20 gatos e 20 cães hígidos. Como resultado dos gatos, foram obtidos os valores de pico de velocidade sistólica, velocidade diastólica final, média da velocidade média, média da velocidade máxima, índice de resistividade e índice de pulsatilidade, tanto da artéria celíaca quanto da artéria mesentérica cranial de animais hígidos não sedados, e; foram obtidos esses mesmos dados das artérias aorta, renal, ilíaca externa e femoral e todos comparados entre os gatos sedados e não sedados, onde não foram encontradas diferenças estatisticamente significativas, exceto na velocidade diastólica final e velocidade média da artéria celíaca, e índice de resistividade e de pulsatilidade da artéria ilíaca. Já nos cães, observou-se que houve diferença de pelo menos dois dos parâmetros dopplervelocimétricos avaliados das artérias selecionadas, exceto da artéria femoral. Dessa forma, nos gatos foram fornecidos parâmetros dopplervelocimétricos da artéria celíaca e mesentérica cranial de animais não sedados, e conclui-se que, enquanto o protocolo utilizado nos gatos, com midazolam, cetamina e butorfanol, não alterou os valores encontrados nos vasos selecionados, exceto da artéria celíaca e da ilíaca; nos cães, o uso de acepromazina e butorfanol levou a modificação de parte desses valores em todos os vasos, exceto na artéria femoral. Assim, na realização deste exame com esses protocolos, essas diferenças devem ser consideradas. / Real time information about direction and type of blood flow can be obtained with Doppler ultrasound. No data was found in the literature regarding values of the celiac and cranial mesenteric artery in cats obtained through this method. Moreover, occasionally, for examining cats and dogs’ vessels about which we desire to get more information, there is a need to sedate these animals. This study has two objectives. One was to evaluate the quantitative aspects of spectral wave formed by the blood flow of aorta, celiac, cranial mesenteric, renal, external iliac and femoral arteries from healthy cats and dogs and compare them to the same animal under sedation, using one protocol for each species. The cats were sedated with midazolam, ketamine and butorphanol and the dogs with acepromazine and butorphanol. The second objective was to obtain velocimetric reference values from celiac and mesenteric cranial artery in cats. Twenty healthy cats and dogs were evaluated. As a result for the cats, values of peak systolic velocity, end diastolic velocity, time averaged mean velocity, time averaged maximum velocity, resistivity index and pulsatility index of both the celiac and the cranial mesenteric artery were obtained in healthy non-sedated animals, and; these same data from aorta, renal, external iliac and femoral were obtained, and all compared, between sedated and non-sedated cats, where statistically significant differences were not found, except in end diastolic velocity and average speed of the celiac artery, and resistance and pulsatility index of the iliac artery. In dogs, a difference was observed in at least two of the Doppler velocity parameters measured of the arteries, except for the femoral artery. Thus, Doppler velocity parameters of the celiac and cranial mesenteric artery in non-sedated cats were provided and it was concluded that the protocol used in cats, with midazolam, ketamina and buthorphanol did not alter the values of Doppler ultrasound in the selected vessels in cats, except celiac and external iliac artery. In addition, in dogs, the use of acepromazine and buthorphanol led to modification of part of these values in all vessels, except in the femoral artery. Thus, when carrying out this examination with these protocols, such differences should be considered.
340

Avaliação das variáveis obtidas pela ultrassonografia com Doppler das grandes artérias abdominais e da femoral em gatos e cães submetidos à sedação.

Mello, Fabíola Peixoto da Silva January 2016 (has links)
Informações em tempo real da direção e tipo de fluxo sanguíneo podem ser obtidas com ultrassonografia com Doppler. Não foram encontrados dados na literatura de valores obtidos por este método da artéria celíaca e mesentérica cranial de gatos. Além disso, ocasionalmente há necessidade de sedar os gatos e cães para realização deste exame em quaisquer vasos em que se deseja obter mais informações. O trabalho possui dois objetivos. Um foi avaliar os aspectos quantitativos da onda espectral formada pelo fluxo sanguíneo das artérias: aorta, celíaca, mesentérica cranial, renal, ilíaca externa e femoral de gatos e cães hígidos; e compará-los aos obtidos dos mesmos animais submetidos à sedação, com um protocolo para cada espécie. Os gatos foram sedados com midazolam, cetamina e butorfanol, e os cães, com acepromazina e butorfanol. Outro objetivo foi obter valores velocimétricos de referência para artéria celíaca e artéria mesentérica cranial em gatos, através do Doppler espectral. Para isso, foram avaliados 20 gatos e 20 cães hígidos. Como resultado dos gatos, foram obtidos os valores de pico de velocidade sistólica, velocidade diastólica final, média da velocidade média, média da velocidade máxima, índice de resistividade e índice de pulsatilidade, tanto da artéria celíaca quanto da artéria mesentérica cranial de animais hígidos não sedados, e; foram obtidos esses mesmos dados das artérias aorta, renal, ilíaca externa e femoral e todos comparados entre os gatos sedados e não sedados, onde não foram encontradas diferenças estatisticamente significativas, exceto na velocidade diastólica final e velocidade média da artéria celíaca, e índice de resistividade e de pulsatilidade da artéria ilíaca. Já nos cães, observou-se que houve diferença de pelo menos dois dos parâmetros dopplervelocimétricos avaliados das artérias selecionadas, exceto da artéria femoral. Dessa forma, nos gatos foram fornecidos parâmetros dopplervelocimétricos da artéria celíaca e mesentérica cranial de animais não sedados, e conclui-se que, enquanto o protocolo utilizado nos gatos, com midazolam, cetamina e butorfanol, não alterou os valores encontrados nos vasos selecionados, exceto da artéria celíaca e da ilíaca; nos cães, o uso de acepromazina e butorfanol levou a modificação de parte desses valores em todos os vasos, exceto na artéria femoral. Assim, na realização deste exame com esses protocolos, essas diferenças devem ser consideradas. / Real time information about direction and type of blood flow can be obtained with Doppler ultrasound. No data was found in the literature regarding values of the celiac and cranial mesenteric artery in cats obtained through this method. Moreover, occasionally, for examining cats and dogs’ vessels about which we desire to get more information, there is a need to sedate these animals. This study has two objectives. One was to evaluate the quantitative aspects of spectral wave formed by the blood flow of aorta, celiac, cranial mesenteric, renal, external iliac and femoral arteries from healthy cats and dogs and compare them to the same animal under sedation, using one protocol for each species. The cats were sedated with midazolam, ketamine and butorphanol and the dogs with acepromazine and butorphanol. The second objective was to obtain velocimetric reference values from celiac and mesenteric cranial artery in cats. Twenty healthy cats and dogs were evaluated. As a result for the cats, values of peak systolic velocity, end diastolic velocity, time averaged mean velocity, time averaged maximum velocity, resistivity index and pulsatility index of both the celiac and the cranial mesenteric artery were obtained in healthy non-sedated animals, and; these same data from aorta, renal, external iliac and femoral were obtained, and all compared, between sedated and non-sedated cats, where statistically significant differences were not found, except in end diastolic velocity and average speed of the celiac artery, and resistance and pulsatility index of the iliac artery. In dogs, a difference was observed in at least two of the Doppler velocity parameters measured of the arteries, except for the femoral artery. Thus, Doppler velocity parameters of the celiac and cranial mesenteric artery in non-sedated cats were provided and it was concluded that the protocol used in cats, with midazolam, ketamina and buthorphanol did not alter the values of Doppler ultrasound in the selected vessels in cats, except celiac and external iliac artery. In addition, in dogs, the use of acepromazine and buthorphanol led to modification of part of these values in all vessels, except in the femoral artery. Thus, when carrying out this examination with these protocols, such differences should be considered.

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