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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.
371

The utility of bioimpedance cardiography in assessing the influence of obstructive sleep apnea hypopnea syndrome on cardiac function

Aron, Adrian 20 April 2010 (has links)
Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS) is a breathing disorder characterized by recurrent episodes of upper airway collapse during sleep. Measuring cardiac function in OSAHS patients may provide information to help delineate not only chronic effects of autonomic imbalance and ventricular loading in the diseases state, but also possible beneficial effects of clinical treatments. Objectives (Study 1): The aim of this study was to determine the reproducibility of select cardiac variables when monitoring a simulated sleep apnea event using a new improved bioimpedance cardiography system. Methods: Fifteen apparently healthy males were tested on three different days in a protocol requiring their performance of two 15 sec and two 30 sec forced and sustained inspiratory efforts against a closed epiglottis (Müeller Maneuver-MM). Results: Changes in cardiac output (CO), heart rate (HR), stroke volume (SV), myocardial contractility index (MCI) and systemic vascular resistance (SVR) were similar during 15 sec and 30 sec MM in all three days. During 30 sec MM, these changes in cardiac function were pronounced in comparison to the minimal variations observed for the 15 sec MM challenge test. Objectives (Study 2): The aim of this study was to characterize the cardiac responses to negative intrathoracic pressure in OSAHS patients with and without hypertension versus healthy subjects. Methods: Two groups of 10 OSAHS patients, one without HTN and one with HTN were compared with a control group. Each subject underwent two 30 sec (MM) as previously described. Results: During MM, there were similar changes in SV, HR and SVR in all three groups. CO was lower during MM in controls compared to OSAHS groups, whereas MCI decreased during MM in both controls and OSAHS+HTN groups (-7.5% and -1.7%, respectively) compared with an increase in OSAHS group (11.8%). During a Post-MM, both OSAHS groups showed return of cardiac responses toward their pre-MM baseline within 30 sec. Conclusions: The new bioimpedance cardiograph evaluated in this study was found to be reliable for measuring acute changes in cardiac responses to this breathing challenge test. OSAHS may cause acute changes in selected cardiac parameters during and immediately after a breathing challenge test. / Ph. D.
372

Obstructive Sleep Apnea Risk in Abdominal Aortic Aneurysm Disease Patients: Associations with Physical Activity Status, Metabolic Syndrome, and Exercise Tolerance

Mabry, J. Erin 03 May 2013 (has links)
Obstructive sleep apnea (OSA) is common in older U.S. adults and the prevalence is anticipated to rise in this age group along with obesity, a prominent risk factor for OSA. Recently, OSA was determined to be highly prevalent among patients with abdominal aortic aneurysm (AAA) disease. Objectives: Examine associations between OSA risk and physical activity (PA), metabolic syndrome (MetSyn), and exercise responses to cardiopulmonary exercise testing (CPET) in elderly patients with AAA disease. Methods: Elderly patients (n=326 for Studies 1 and 2; n=114 for Study 3) newly diagnosed with small AAAs (aortic diameter "2.5 and < 5.5 cm) were recruited. Data collection for all participants included: extraction of medical history and drug information from medical records; completion of a physical examination to assess resting vital signs and anthropometrics; fasting blood draw for several biochemical analyses; completion of a cardiopulmonary exercise test (CPET); and completion of interviews and questionnaires for health history, PA, and OSA risk. Results: 57% of subjects were High-risk for OSA and 17% were classified in the highest-risk Berlin Risk Score (BRS) 3 group; these subjects reported fewer blocks walked/day, flights of stairs climbed/day, and expended fewer Calories when engaged in these activities compared to Low-risk counterparts, independent of obesity. Among those at High-risk for OSA, 45% had MetSyn. Subjects with the highest BRS also had the highest prevalence of MetSyn and values for the MetSyn component biomarkers. Exercise capacity and physiological responses at rest, during exercise, and recovery were similar between groups at High- and Low-risk for OSA. Conclusions: Reduced levels of PA among elderly AAA patients at High-risk for OSA could have unfavorable implications for cardiovascular disease (CVD) risk and all-cause and CVD mortality.  Subjects demonstrating the most clinical symptoms of OSA showed a significantly higher prevalence for MetSyn and several of the biomarkers that determine MetSyn. In clinical practice, the BRS may be useful for identifying those AAA patients at increased risk for both OSA and MetSyn. / Ph. D.
373

Modificação da via aérea superior com uso de CPAP: avaliação por faringometria acústica em apnéicos graves e roncadores simples / Upper airway reconfiguration with CPAP: acoustic pharyngometry evaluation in severe apneics and simple snorers

Cláudia Inês Guerra de Sousa Silva 28 May 2014 (has links)
Introdução: A Apneia Obstrutiva do Sono (AOS) é uma doença crônica e evolutiva que tem uma alta prevalência e pode acarretar graves repercussões hemodinâmicas, neurológicas e comportamentais. A pressão positiva contínua na via aérea (CPAP) é altamente eficaz no tratamento da AOS, porém o processo de expansão da faringe por este dispositivo não é totalmente entendido. A faringometria acústica (FA) é um método de mensuração das dimensões da cavidade oral e da faringe, reprodutível e fácil de efetuar, podendo avaliar eficientemente os efeitos do CPAP na faringe e trazer informações sobre sua complacência e sítios de obstrução. Objetivo: avaliar as mudanças induzidas pelo CPAP nas dimensões da faringe e no posicionamento do palato mole em pacientes com AOS e verificar se a deformabilidade da via aérea superior pelo CPAP é maior em apneicos graves do que em roncadores simples. Desenho do estudo: estudo prospectivo. Métodos: 48 pacientes foram submetidos a FA durante o uso do CPAP. 29 pacientes com índice de apneia e hipopneia (IAH) >30 e indicação de uso do CPAP foram inclusos no grupo AOS, e 19 pacientes com IAH <=5 foram inclusos no grupo controle. Os critérios de inclusão foram: idade entre 18 e 65 anos, ambos os sexos, polissonografia (PSG) previamente realizada, e PSG para titulação do CPAP no grupo AOS. Os critérios de exclusão foram: obstrução nasal crônica pré existente, uso de medicamentos psiquiátricos, neurológicos ou miorrelaxantes, insuficiência cardíaca congestiva, índice de massa corpórea >= 35 e cirurgia palatal prévia para AOS. Os gráficos resultantes dos exames de FA foram analisados por 2 examinadores cegos que marcaram os pontos para obtenção da distância da transição orofaríngea da glote. Foram calculados também o comprimento e o volume da faringe pelo programa do aparelho. Foi então feita a análise estatística para comparar as medidas em diferentes pressões intragrupo e intergrupo. Resultados: As medidas dos dois examinadores mostraram correlação. O CPAP não ocasionou nenhum aumento significativo na via aérea faríngea nem mudou o posicionamento do palato em ambos os grupos. No estado basal, os pacientes com AOS têm uma faringe mais longa do que os roncadores simples. Após a aplicação do CPAP, não houve diferença no comprimento e no volume da faringe entre os grupos. Conclusões: Não houve diferenças significantes na posição da transição orofaríngea e da glote entre roncadores e apneicos com a aplicação de CPAP. Não houve expansão significante na via aérea faríngea com a aplicação de CPAP nos roncadores e apneicos. Anatomicamente, os apneicos apresentaram via aérea superior mais longa que os roncadores simples / Rationale: Obstructive Sleep Apnea (OSA) is an evolutive disease, with a high prevalence, that can cause serious hemodynamic, neurological and behavioral repercussions. Continuous positive airway pressure (CPAP) is highly effective in OSA treatment, however the pharynx expansion by this advice is not fully understood. Acoustic pharyngometry (AP) is a measurement method of oral cavity and pharynx dimensions, and can efficiently evaluate CPAP effects on pharynx, bringing informations about its compliance and sites of obstruction. Objectives/Hypothesis: To verify if the CPAP-induced deformability on the pharynx and soft palate is greater in obstructive sleep apnea (OSA) patients than in simple snorers. Study Design: Prospective study. Methods: 29 patients with severe OSA and 19 simple snorers underwent acoustic pharyngometry measurements while awake in supine position. Measurements were first made without CPAP, and then with a nasal CPAP starting with 4cmH2O and up to 10cmH2O. The oropharyngeal transition and the position of the glottis were marked in the generated curves by two blinded examiners. The marked values were averaged to calculate the oropharyngeal transition and the pharyngeal length and volume under zero, 4 and 10cmH2O of CPAP for each group. Results: CPAP did not produce any significant enlargement in the pharyngeal airway nor changed the soft palate positioning in both groups. At baseline, OSA patients have a longer pharynx than simple snorers. After the application of CPAP, there was no difference in the length and volume of the pharynx between groups. Conclusions: There were no significant differences in the position of oropharyngeal junction and glottis between snorers and apneics with CPAP appliance. There was no significant expansion in pharyngeal airway with CPAP appliance in snorers and apneics. Anatomically, apneics presented a longer superior airway than simple snorers
374

Modificação da via aérea superior com uso de CPAP: avaliação por faringometria acústica em apnéicos graves e roncadores simples / Upper airway reconfiguration with CPAP: acoustic pharyngometry evaluation in severe apneics and simple snorers

Silva, Cláudia Inês Guerra de Sousa 28 May 2014 (has links)
Introdução: A Apneia Obstrutiva do Sono (AOS) é uma doença crônica e evolutiva que tem uma alta prevalência e pode acarretar graves repercussões hemodinâmicas, neurológicas e comportamentais. A pressão positiva contínua na via aérea (CPAP) é altamente eficaz no tratamento da AOS, porém o processo de expansão da faringe por este dispositivo não é totalmente entendido. A faringometria acústica (FA) é um método de mensuração das dimensões da cavidade oral e da faringe, reprodutível e fácil de efetuar, podendo avaliar eficientemente os efeitos do CPAP na faringe e trazer informações sobre sua complacência e sítios de obstrução. Objetivo: avaliar as mudanças induzidas pelo CPAP nas dimensões da faringe e no posicionamento do palato mole em pacientes com AOS e verificar se a deformabilidade da via aérea superior pelo CPAP é maior em apneicos graves do que em roncadores simples. Desenho do estudo: estudo prospectivo. Métodos: 48 pacientes foram submetidos a FA durante o uso do CPAP. 29 pacientes com índice de apneia e hipopneia (IAH) >30 e indicação de uso do CPAP foram inclusos no grupo AOS, e 19 pacientes com IAH <=5 foram inclusos no grupo controle. Os critérios de inclusão foram: idade entre 18 e 65 anos, ambos os sexos, polissonografia (PSG) previamente realizada, e PSG para titulação do CPAP no grupo AOS. Os critérios de exclusão foram: obstrução nasal crônica pré existente, uso de medicamentos psiquiátricos, neurológicos ou miorrelaxantes, insuficiência cardíaca congestiva, índice de massa corpórea >= 35 e cirurgia palatal prévia para AOS. Os gráficos resultantes dos exames de FA foram analisados por 2 examinadores cegos que marcaram os pontos para obtenção da distância da transição orofaríngea da glote. Foram calculados também o comprimento e o volume da faringe pelo programa do aparelho. Foi então feita a análise estatística para comparar as medidas em diferentes pressões intragrupo e intergrupo. Resultados: As medidas dos dois examinadores mostraram correlação. O CPAP não ocasionou nenhum aumento significativo na via aérea faríngea nem mudou o posicionamento do palato em ambos os grupos. No estado basal, os pacientes com AOS têm uma faringe mais longa do que os roncadores simples. Após a aplicação do CPAP, não houve diferença no comprimento e no volume da faringe entre os grupos. Conclusões: Não houve diferenças significantes na posição da transição orofaríngea e da glote entre roncadores e apneicos com a aplicação de CPAP. Não houve expansão significante na via aérea faríngea com a aplicação de CPAP nos roncadores e apneicos. Anatomicamente, os apneicos apresentaram via aérea superior mais longa que os roncadores simples / Rationale: Obstructive Sleep Apnea (OSA) is an evolutive disease, with a high prevalence, that can cause serious hemodynamic, neurological and behavioral repercussions. Continuous positive airway pressure (CPAP) is highly effective in OSA treatment, however the pharynx expansion by this advice is not fully understood. Acoustic pharyngometry (AP) is a measurement method of oral cavity and pharynx dimensions, and can efficiently evaluate CPAP effects on pharynx, bringing informations about its compliance and sites of obstruction. Objectives/Hypothesis: To verify if the CPAP-induced deformability on the pharynx and soft palate is greater in obstructive sleep apnea (OSA) patients than in simple snorers. Study Design: Prospective study. Methods: 29 patients with severe OSA and 19 simple snorers underwent acoustic pharyngometry measurements while awake in supine position. Measurements were first made without CPAP, and then with a nasal CPAP starting with 4cmH2O and up to 10cmH2O. The oropharyngeal transition and the position of the glottis were marked in the generated curves by two blinded examiners. The marked values were averaged to calculate the oropharyngeal transition and the pharyngeal length and volume under zero, 4 and 10cmH2O of CPAP for each group. Results: CPAP did not produce any significant enlargement in the pharyngeal airway nor changed the soft palate positioning in both groups. At baseline, OSA patients have a longer pharynx than simple snorers. After the application of CPAP, there was no difference in the length and volume of the pharynx between groups. Conclusions: There were no significant differences in the position of oropharyngeal junction and glottis between snorers and apneics with CPAP appliance. There was no significant expansion in pharyngeal airway with CPAP appliance in snorers and apneics. Anatomically, apneics presented a longer superior airway than simple snorers
375

Treatment effects with a mandibular advancement appliance and uvulopalatopharyngoplasty in obstructive sleep apnea -randomised controlled trials-

Walker-Engström, Marie-Louise January 2003 (has links)
<p>Enthusiasm for uvulopalatopharyngoplasty (UPPP) in the treatment of mild-to-moderate obstructive sleep apnea syndrome (OSAS) has declined in recent years, partly because of a lower success rate over time and partly because of adverse effects. In more severe cases, the patients are generally treated with nasal continuous positive airway pressure (CPAP). However, many patients do not satisfactorily tolerate CPAP as a result of frequent side-effects. Consequently, there is a need for an alternative treatment. Reports on the beneficial effects of mandibular advancement appliances in the treatment of mild-to-moderate OSA exist in the form of short–term evaluations.</p><p>One of the aims of the present thesis was to compare treatment effects with a mandibular advancement appliance and UPPP in patients with OSA with follow-up after one and four years. Ninety-five male patients with confirmed mild-to-moderate OSA (apnea index, AI >5 and <25) were randomised to treatment with a dental appliance or UPPP. Sleep studies were performed before and one and four years after intervention. According to the criteria for normalisation (AI<5 and apnea hypopnea index, AHI<10), 78% of the patients in the dental appliance group and 51% of the patients in the UPPP group had normalised after one year (p<0.05). Still after four years of treatment, 63% of the patients in the dental appliance group and 33% of the patients in the UPPP group were normalised. The dental appliance group had a higher normalisation rate than the UPPP group, but the efficacy was partly invalidated by the compliance rate of 62%.</p><p>Quality of life assessments in the dimensions of vitality, contentment and sleep improved in both groups at the one-year follow-up after treatment. There was no difference between the groups in terms of vitality and sleep. The UPPP group, however, reported a higher degree of contentment than the dental appliance group, even though the somnographic values were superior in the latter group. </p><p>Another aim was to conduct a randomised study to test the hypothesis that severe OSA patients will benefit from more pronounced mandibular advancement (MA) compared with a shorter advancement. Eighty-six males with severe OSA (AI>20) were randomly allocated to either 75% or 50% MA for a six-month treatment period. Treatment with a more pronounced mandibular advancement yielded a 20% higher normalisation rate than a shorter advancement. A mean normalisation rate of 45% was found for patients in this category with few side-effects, good patient satisfaction and a compliance of 92% after 6 months. </p><p>The overall conclusion is that dental appliance treatment is effective in patients with mild to moderate OSA and even for patients with severe OSA. The efficacy in terms of normalisation in patients with mild to moderate OSA was higher after the dental appliance treatment with a 50% degree of advancement than after the UPPP treatment. However, severe OSA patients might benefit from more pronounced advancement (75%) compared with a shorter degree of advancement (50%). QOL improved significantly after both dental appliance and UPPP treatment. </p>
376

Treatment effects with a mandibular advancement appliance and uvulopalatopharyngoplasty in obstructive sleep apnea -randomised controlled trials-

Walker-Engström, Marie-Louise January 2003 (has links)
Enthusiasm for uvulopalatopharyngoplasty (UPPP) in the treatment of mild-to-moderate obstructive sleep apnea syndrome (OSAS) has declined in recent years, partly because of a lower success rate over time and partly because of adverse effects. In more severe cases, the patients are generally treated with nasal continuous positive airway pressure (CPAP). However, many patients do not satisfactorily tolerate CPAP as a result of frequent side-effects. Consequently, there is a need for an alternative treatment. Reports on the beneficial effects of mandibular advancement appliances in the treatment of mild-to-moderate OSA exist in the form of short–term evaluations. One of the aims of the present thesis was to compare treatment effects with a mandibular advancement appliance and UPPP in patients with OSA with follow-up after one and four years. Ninety-five male patients with confirmed mild-to-moderate OSA (apnea index, AI &gt;5 and &lt;25) were randomised to treatment with a dental appliance or UPPP. Sleep studies were performed before and one and four years after intervention. According to the criteria for normalisation (AI&lt;5 and apnea hypopnea index, AHI&lt;10), 78% of the patients in the dental appliance group and 51% of the patients in the UPPP group had normalised after one year (p&lt;0.05). Still after four years of treatment, 63% of the patients in the dental appliance group and 33% of the patients in the UPPP group were normalised. The dental appliance group had a higher normalisation rate than the UPPP group, but the efficacy was partly invalidated by the compliance rate of 62%. Quality of life assessments in the dimensions of vitality, contentment and sleep improved in both groups at the one-year follow-up after treatment. There was no difference between the groups in terms of vitality and sleep. The UPPP group, however, reported a higher degree of contentment than the dental appliance group, even though the somnographic values were superior in the latter group. Another aim was to conduct a randomised study to test the hypothesis that severe OSA patients will benefit from more pronounced mandibular advancement (MA) compared with a shorter advancement. Eighty-six males with severe OSA (AI&gt;20) were randomly allocated to either 75% or 50% MA for a six-month treatment period. Treatment with a more pronounced mandibular advancement yielded a 20% higher normalisation rate than a shorter advancement. A mean normalisation rate of 45% was found for patients in this category with few side-effects, good patient satisfaction and a compliance of 92% after 6 months. The overall conclusion is that dental appliance treatment is effective in patients with mild to moderate OSA and even for patients with severe OSA. The efficacy in terms of normalisation in patients with mild to moderate OSA was higher after the dental appliance treatment with a 50% degree of advancement than after the UPPP treatment. However, severe OSA patients might benefit from more pronounced advancement (75%) compared with a shorter degree of advancement (50%). QOL improved significantly after both dental appliance and UPPP treatment.
377

Das Schlafapnoe-Syndrom bei Dialysepatienten / The sleep apnea syndrome with dialysis patients

Weidler, Oliver 28 September 2010 (has links)
No description available.
378

Contribution à l'étude de la relation entre l'activité cérébrale et la variabilité du rythme cardique au cours du sommeil / Contribution of the study of the dynamic interaction between sleep EEG and heart rate variability

Jurysta, Fabrice 21 May 2010 (has links)
Doctorat en Sciences médicales / info:eu-repo/semantics/nonPublished
379

Asociación entre la mala autopercepción de salud bucal y los síntomas del síndrome de apnea obstructiva del sueño (SAOS) en adultos de los Estados Unidos de América / Association between negative self-perception of oral health and symptoms of obstructive sleep apnea disorders syndrome (OSAS) in adults from the United States of America

Canales Donaires, Jose Maria, Moncada Araujo, Romina Franchesca 07 March 2022 (has links)
Objetivo: Determinar la asociación de la mala autopercepción de la salud bucal con los síntomas del síndrome de apnea obstructiva del sueño (SAOS) en población adulta de los Estados Unidos de América. Materiales y métodos: Se realizó un estudio observacional transversal retrospectivo analítico, con un total de 2348 personas entre las edades comprendidas de 15 a 55 años tomadas de las encuestas National Health Nutrition Examination Survey (NHANES) durante el periodo 2015-2016 realizadas por el Center Disease Control and Prevention (CDC) de los Estados Unidos de América. Para la evaluación de ambas variables se emplearon preguntas de auto reporte. Asimismo, la comparación de la mala autopercepción de salud bucal con las características de los participantes se realizó mediante la prueba estadística Chi cuadrado. Para asociar la mala autopercepción de salud bucal con los síntomas del síndrome de apnea obstructiva del sueño (SAOS) se usó la regresión de Poisson para asociar la razón de prevalencia cruda y ajustada con un nivel de significancia de p < 0.05 e IC (95%). Resultados: Al asociar la mala autopercepción de salud bucal con los síntomas del síndrome de apnea obstructiva del sueño (SAOS), no se encontró asociación estadísticamente significativa p > 0.05. El 9.5% de participantes del sexo femenino tienen una mayor frecuencia de presentar una mala autopercepción de salud bucal en comparación al sexo opuesto. Conclusiones: En el presente estudio se observó que, la autopercepción de salud bucal no está relacionada con los síntomas tales como la somnolencia y ronquidos del síndrome de apnea obstructiva del sueño (SAOS). / Aim: Determine the association of negative self-perception of oral health with symptoms of obstructive sleep apnea syndrome (OSAS) disorders in the population aged 15 to 55 years of the United States of America. Materials and methods: An analytical retrospective cross-sectional observational study was carried out, with a total of 2348 people between the ages of 15 and 55 years taken from the National Health Nutrition Examination Survey (NHANES) during the period 2015-2016 carried out by the Center Disease Control and Prevention (CDC) of the United States of America. For the evaluation of both variables, self-report questions were used. Likewise, the comparison of the poor self-perception of oral health with the characteristics of the participants was carried out using the Chi square statistical test. To associate poor self-perceived oral health with obstructive sleep apnea syndrome (OSAS) symptoms, Poisson regression was used to associate crude and adjusted prevalence ratios with a significance level of p < 0.05 and CI (95%). Results: When associating poor self-perception of oral health with symptoms of obstructive sleep apnea syndrome (OSAS), no statistically significant association was found p > 0.05. While 9.5% of female participants have a higher frequency of presenting a poor self-perception of oral health compared to the opposite sex. Conclusions: In the present study, it was observed that oral health self-perception is not related to symptoms such as sleepiness and snoring of obstructive sleep apnea syndrome (OSAS) disorders. / Tesis
380

Obstructive sleep apnea and cardiometabolic complications

Lam, Chung-mei, Jamie., 林頌眉. January 2009 (has links)
published_or_final_version / Medicine / Master / Doctor of Medicine

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