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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.
91

Apnea and bradycardia elicited by facial airstream stimulation in healthy infants in the first year of life implications for detection of infants at risk for sudden infant death syndrome /

Hurwitz, Barry Elliot, January 1984 (has links)
Thesis (Ph. D.)--University of Florida, 1984. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 125-142).
92

Computational mechanics models for studying the pathogenesis of obstructive sleep apnea (OSA) /

Xu, Chun. Wootton, David Macmullen. January 2006 (has links)
Thesis (Ph. D.)--Drexel University, 2006. / Includes abstract and vita. Includes bibliographical references (leaves 121-134).
93

Intermittent hypoxia activation of the sympathetic nervous system /

Lusina, Sarah-Jane C. January 1900 (has links)
Thesis (M.S.)--University of British Columbia, 2005. / Includes bibliographical references (leaves 89-97). Also available online (PDF file) by a subscription to the set or by purchasing the individual file.
94

Intermittent hypoxia activation of the sympathetic nervous system /

Lusina, Sarah-Jane C. January 1900 (has links)
Thesis (M.S.)--University of British Columbia, 2005. / Includes bibliographical references (leaves 89-97).
95

Efeito do uso de aparelho intraoral no tratamento do ronco primario e apneia obstrutiva do sono / Effect of intraoral appliance to treat primary snore and sleep obstructive apnea

Ribeiro, Cynthia Valeria Silva Gomes 30 August 2005 (has links)
Orientador: Altair Antoninha Del Bel Cury / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-05T09:25:29Z (GMT). No. of bitstreams: 1 Ribeiro_CynthiaValeriaSilvaGomes_M.pdf: 3852161 bytes, checksum: 491f5853c6ba25e4f30b324e92d65238 (MD5) Previous issue date: 2005 / Resumo: Distúrbios respiratórios do sono são condições patológicas freqüentes. Dentre estes, destaca-se o Ronco Primário que quase sempre causa conflitos sociais e familiares, podendo ocorrer isoladamente ou fazendo parte de um quadro clínico mais severo, a Síndrome da Apnéia Obstrutiva do Sono. Esta por sua vez, além da presença do ronco que ocorre em mais de 90% dos casos, é também caracterizada por paradas respiratórias, microdispertares, dessaturações de oxigênio sanguíneo, desestruturação do sono, sonolência diurna importante, aumento da possibilidade de hipertensão arterial sistêmica, infarto do miocárdio, acidente vascular encefálico, envolvimento em acidentes de trabalho e de trânsito, assim como comprometimento da memória, cognição e atenção. A Síndrome da Apnéia Obstrutiva do Sono pode ser subdividida em três níveis (leve, moderada e grave), considerando o índice de apnéia/hipopnéia. As formas de tratamento incluem principalmente a cirurgia, pressão aérea positiva contínua (CPAP) e aparelhos intraorais. Este estudo investigou com o exame de polissonografia, os efeitos do uso de aparelho intraoral de protrusão mandibular, em onze voluntários com idade entre 23 e 62 anos, sendo 63,6% do gênero masculino e 36,4% feminino. Destes, dois apresentavam ronco primário, dois apnéia grave, quatro apnéia moderada e três apnéia leve. Os pacientes foram avaliados através de polissonografia, antes e após o uso do aparelho intraoral, tendo sido estudadas as seguintes variáveis: índices de apnéia/hipopnéia, dessaturação de oxigênio, número de apnéias, número de hipopnéias e ronco. Este foi avaliado quanto à intensidade e freqüência esporádica ou ausente. Na Análise Estatística foi utilizado o teste t de Student para as variáveis: índice de Apnéia e Hipopnéia, Saturação Mínima de Oxigênio, Número total de Apnéias e Número Total de Hipopnéias. As variáveis Escala de Graduação do Ronco, Grau de Sonolência Diurna e Ruído do Ronco, foram analisadas pelo Teste de Wilcoxon das ordens assinaladas, com intervalo de confiança de 95%. Em todas as análises foi adotado um nível de significância de 5% (a =0,05). Os resultados mostraram que todos os voluntários tiveram redução significativa nas variáveis estudadas. Todos os indivíduos com Ronco Primário obtiveram resolução completa do problema. No grupo de Apnéia leve, todos os voluntários passaram a apresentar exame de polissonografia normais; Apnéia moderada, 75% também obtiveram exame normal e em 25% a apnéia passou de grau moderado para leve. Considerando os que apresentavam Apnéia grave, 50% passaram a apresentar apnéia moderada e 50% apnéia leve. Dessa forma pode-se concluir que o uso de aparelho intraoral é uma forma de tratamento eficiente para o ronco primário e apnéia obstrutiva do sono / Abstract: Snoring is a noise that occurs during sleep when the people are breathing in and there is some blockage of air passing through the back of the mouth and it is a frequent pathological conditions called Primary Snore. This snore can be or not be associated with more serious problems, such as obstructive sleep apnea syndrome (OSAS), frequent arousals from sleep, or inability of the lungs to breathe in sufficient oxygen. It is also characterized by excessive daytime sleepiness or fatigue. Patients also may complain of difficulty with concentration, morning headaches, impotence, difficulty sleeping, or restless sleep. Obstructive Sleep Syndrome Apnea can be subdivided in three levels (Iight, moderate and serious), considering the apnea/hipopnea index. The treatment forms include surgery, positive aerial pressure continuous (CPAP) and oral appliance. This study investigated the effects of the use of oral appliance by moving either the tongue or the mandible anteriorly, partially relieving apneas in eleven volunteers with age between 23 and 62 years, being 63,6% of the male gender and 36,4% of female. The volunteers were undergo polysomnography exam, Scale of Graduation of the Snore, Epworth Sleepiness Scale and Snore. After these exams two volunteers were diagnosed as primary snore, two serious apnea, four moderate apnea and three light apnea. The patients were appraised through ali exams before (TO) and after (T1) the use of the oral appliance. The data were statistically analyzed by t Student test for Apnéia I Hypopnea Index, Minimum Saturation of Oxygen, total Number of Apneas and Total Number of Hypopneas and by Wilcoxon signaled orders test to Scale of Graduation of the Snore, Epworth Sleepiness Scale and Snore, they were analyzed by the Test of Wilcoxon with 95% levei of confidence. The results showed that ali the volunteers had significant reduction in the studied variables. Ali the individuais with Primary Snore obtained complete resolution of their problem. Also the volunteers suffering from OSAS had a reduction in their polysomnography exams. Within the limits of this study, it can be concluded that the use of oral appliance was efficient treatment to the Primary Snore and Obstructive Sleep Syndrome Apnea / Mestrado / Protese Dental / Mestre em Clínica Odontológica
96

Ambulatory diagnostic and monitoring techniques for sleep disordered breathing.

Bruyneel, Marie 22 September 2015 (has links)
Techniques ambulatoires de diagnostic et de monitoring des troubles respiratoires liés au sommeil.Le syndrome d’apnées obstructives du sommeil (SAOS) est un trouble du sommeil très fréquent, fortement lié à l’obésité, ce qui explique sa prévalence en pleine expansion. En parallèle, la demande d’examens polysomnographiques (PSG) en laboratoire du sommeil, méthode diagnostique de référence, est en croissance. Comme l’accès à cette technique est peu aisé, de nombreux appareils simplifiés d’enregistrement de sommeil ont été récemment développés, mais restent imparfaits (mauvaise évaluation du temps de sommeil, sous-estimation de la sévérité du SAOS, faux négatifs, taux d’échec élevé) et sont d’un apport limité pour le diagnostic du SAOS. La PSG au domicile (PSG-d) est une alternative bien plus informative, permettant d’éviter nombre des désavantages rencontrés par l’usage d’appareils simplifiés. Nous l’avons dès lors étudiée pour le diagnostic du SAOS, au travers d’une étude randomisée comparant la PSG-d vs la PSG hospitalière. En termes d’efficacité diagnostique, les résultats sont excellents, avec un faible taux d’échec d’examens à domicile (4.7 vs 1.5%). Les patients préfèrent être enregistrés dans leur propre environnement où la qualité de leur sommeil est d’ailleurs meilleure. Nous avons ensuite voulu faire le point sur la littérature récente au travers d’un article de revue, en analysant les études prospectives randomisées comparant la PSG-d et au labo du sommeil. Les résultats de ces études concordent pour démontrer que la PSG-d constitue une excellente alternative aux tests réalisés à l’hôpital. Outre le SAOS, l’outil permet le diagnostic d’autres troubles du sommeil, comme les mouvements périodiques des jambes durant le sommeil, les troubles du rythme circadien, Une question restée jusqu’ici sans réponse était l’influence de la localisation du branchement des PSG-d, à l’hôpital ou à domicile. Une étude prospective randomisée nous a permis d’établir que la localisation du branchement des PSG-d n’influençait pas la qualité globale de l’examen, ce qui simplifiera l’utilisation de cet outil à l’avenir. Enfin, nous avons utilisé des techniques de télé monitoring (TM) pour contrôler, en temps réel, la qualité des PSG-d. Dans une première étude pilote, la faisabilité a été confirmée, malgré quelques difficultés techniques. Nous avons voulu appliquer la technique à une population de patients souffrant d’un syndrome coronarien aigu, incapables d’être enregistrés au labo du sommeil. Nous avons étudié la qualité du screening du SAOS par PSG vs polygraphie (PG). Les résultats se sont révélés surprenants :82% de cette population présentait des troubles respiratoires liés au sommeil, principalement centraux. La PSG était nettement plus sensible que la PG, et le TM améliorait la qualité des PSG. Chez les patients traités pour SAOS, nous avons ensuite utilisé un outil de monitoring, l’actigraphie (Act), afin d’observer, dans la vie de tous les jours, les changements de schémas de sommeil et d’activité physique engendrés par la pression positive continue (PPC). Dans un premier travail, rétrospectif, nous avons observé ces paramètres chez des SAOS avant traitement, puis au travers d’une étude prospective multicentrique, nous avons suivi 150 patients avant et après PPC, et observé chez eux une augmentation de temps de sommeil, mais pas de l’activité physique. En conclusion, nous avons démontré dans cette thèse l’intérêt clinique de deux excellents outils ambulatoires, la PSG-d et l’Act, pour la prise en charge du SAOS. Les implications potentielles sont une meilleure accessibilité diagnostique pour le SAOS, une initiation thérapeutique plus précoce et un suivi plus précis des SAOS traités, dans des conditions ambulatoires, plus confortables et plus adéquates pour les patients. / Ambulatory diagnostic and monitoring techniques for sleep disordered breathingSleep disordered breathing (SDB), including obstructive sleep apnea syndrome (OSAS), is directly related to obesity. Significant morbi-mortality is associated with OSAS, explaining the increasing demand for in-hospital polysomnography (PSG), the reference diagnostic method. As this technique is complex and time-consuming, many simplified portable monitoring (PM) devices for home sleep testing have been developed. However, the ability of PM devices to detect OSA remains limited: sleep time is not correctly assessed, OSA severity is underestimated, false negative results occur and the failure rate of the tests is high, up to 30%. Home-PSG (H-PSG) is an interesting alternative, avoiding many of these drawbacks. In the first part of this work, we studied the tool in an original study comparing H-PSG and in-lab PSG. Diagnostic efficacy was good and the failure rate low (4.7 vs 1.5%). Patients slept in their own environment and thus sleep quality was better. We were then interested by reviewing recent literature data regarding prospective randomised trials comparing H-PSG and in-lab PSG. We concluded that H-PSG is an excellent alternative for in-lab PSG, allowing not only OSA detection but also diagnosis of a large panel of other sleep disorders (periodic leg movements during sleep, circadian disorders,). As the best place to perform set-up for H-PSG remained unknown, we studied, in another prospective randomised study, the recording’s quality obtained in both settings. As no difference was observed, lab set up was found to be the simpler option for performing H-PSG. We then tested, in a prospective pilot study, real-time telemonitoring (TM) of H-PSG in order to enhance recording quality. Results were encouraging but we faced some technical problems. In a second study, we applied TM coupled with PSG to detect SDB in acute coronary syndrome, in patients too unstable to come in the sleep lab. We compared also PSG results to polygraphy (PG). Surprisingly, 82% of patients suffered from SDB. PSG was much more sensitive than PG to screen SDB in this population and TM improves recording quality. In the second part of this work, we have used actigraphy (Act) to assess sleep and physical activity in OSA patients in real-life conditions. Firstly, in a retrospective study, we documented these parameters before treatment. In a second multicentre study, we evaluated the changes in sleep schemes and physical activity under continuous positive airway pressure (CPAP) in 150 OSA patients. We observed that sleep time was increased under CPAP, but physical activity was not improved, contrarily to sleepiness and quality of life. In conclusion, we have shown through these works the clinical interest of two excellent ambulatory tools, H-PSG and Act, for OSA management. Potential clinical implications include enhanced healthcare accessibility, earlier treatment initiation and a closer follow-up of treated patients, through ambulatory tools, in a comfortable environment for the patients. / Doctorat en Sciences médicales (Médecine) / info:eu-repo/semantics/nonPublished
97

Impaired Functional Capacity Predicts Mortality in Patients with Obstructive Sleep Apnea

Nisar, Shiraz A., Muppidi, Raghunandan, Duggal, Sumit, Hernández, Adrian V., Kalahasti, Vidyasagar, Jaber, Wael, Minai, Omar A. 16 December 2014 (has links)
oam1998@outlook.com / Background: Obstructive sleep apnea (OSA) is associated with increased mortality, for which impaired functional capacity (IFC) has been established as a surrogate. We sought to assess whether IFC is associated with increased mortality in patients with OSA and whether IFC is predictive of increased mortality after accounting for coronary artery disease. Methods: Patients with OSA who underwent both polysomnography testing and exercise stress echocardiogram were selected. Records were reviewed retrospectively for demographics, comorbidities, stress echocardiographic parameters, and polysomnography data. Univariable and multivariable logistic regression analysis was used to evaluate the association between IFC and overall mortality. We then evaluated the variables associated with IFC in the overall population and in the subgroup with normal Duke treadmill score (DTS). Results: In our cohort, 404 (26%) patients had IFC. The best predictors of IFC were female sex, history of smoking, ejection fraction less than 55, increased body mass index, presence of comorbidities, abnormal exercise echocardiogram, abnormal heart rate recovery, and abnormal DTS. Compared with those without IFC, patients with IFC were 5.1 times more likely to die (odds ratio [OR], 5.1; 95% confidence interval [CI], 2.5–10.5; P , 0.0001) by univariate analysis and 2.7 times more likely to die (OR, 2.7; 95% CI, 1.2–6.1; P = 0.02) by multivariate analysis, when accounting for heart rate recovery, DTS, and sleep apnea severity. Among those without coronary artery disease, patients with IFC were at significantly increased risk of mortality (OR, 4.3; 95% CI, 1.35–13.79; P = 0.0088) compared with those with preserved functional capacity. Conclusions: In our OSA population, IFC was a strong predictor of increased mortality. Among those with normal DTS, IFC identified a cohort at increased risk of mortality.
98

Practice Assessment for Adoption of the STOP-Bang Screening Tool

Rosenfield, Scott Patrick, Rosenfield, Scott Patrick January 2017 (has links)
Patients undergoing surgery with unrecognized obstructive sleep apnea (OSA) are at greater risk of complications. Ninety percent of those affected in the United States remain undiagnosed. To improve identification, screening tools such as the STOP-Bang questionnaire (Chung et al. 2008), provide anesthesia providers a method of detecting undiagnosed OSA. The purpose of this study is to assess anesthesia providers' practice of preoperative screening for OSA. An email survey was conducted at a Level-III trauma center in Phoenix, Arizona. The survey consisted of a 13 question, 5-point Likert scale questionnaire. It was sent to 29 Certified Registered Nurse Anesthetists (CRNA). A total of 8 CRNA's responded. Respondents were either neutral or disagreed that current methods of OSA screening works well and generally agree that the STOP-Bang tool would provide an advantage over the current methods, accurately detect OSA, and inform their anesthetic plan over current methods. Respondents leaned towards strong agreement that improving the recognition of undiagnosed OSA is needed. However, they were generally neutral on agreement that the STOP-Bang is necessary at their facility. Respondents agreed that the STOP-Bang tool is easy to use and interpret. However, most agreed that integrating the tool would add complexity to the preanesthesia evaluation but they remained neutral on whether it would add significant time to this process. Respondents were neutral on their observations that the STOP-Bang tool would improve early detection of OSA or reduce perianesthesia complications. Just 25% of respondents reported being aware of the existence of the STOP-Bang tool and none reported having used it. In conclusion, this project demonstrates that some providers have not used the STOP-Bang screening tool to detect undiagnosed OSA, but agree this tool is preferred over their current method. Results from the survey brought insight to a potential quality improvement strategy related to improving the perianesthesia care of patients with undiagnosed OSA. Improving knowledge through dissemination of evidence illustrates the value of the STOP-Bang prior to piloting the tool. The rates of perioperative complications justify the implementation of perioperative strategies such as the STOP-Bang as a tool for anesthesia providers.
99

The Effect of Acute Intermittent Hypoxia on Postprandial Lipid Metabolism

Morin, Renée 22 May 2020 (has links)
Background: Obstructive sleep apnea (OSA) consists of repeated, involuntary breathing suspension during sleep. These events induce rapid depletion/repletion of blood/tissue oxygen content, a phenomenon known as intermittent hypoxia. Aside from causing daytime sleepiness, the most important health consequence of OSA is a 2-fold increase in cardiovascular (CVD) risk. Animal studies provide evidence that intermittent hypoxia, a simulating model of OSA, causes important rise in plasma TG, especially in the postprandial state. However, the underpinning mechanisms linking intermittent hypoxia to altered postprandial TG levels remain unknown. As such, the objective of this study was to characterize the effects of acute intermittent hypoxia on postprandial TG levels in 2 distinct lipoprotein subtypes in humans: chylomicrons which are secreted by the intestine and carry dietary lipids, and denser TG carriers (mainly VLDL) which are secreted by the liver and carry endogenous lipids. Methods: The research consisted of a randomized crossover design. In collaboration with the Sleep laboratory at Montfort Hospital, 7 individuals diagnosed with moderate sleep apnea were recruited through phone calls as well as 8 healthy individuals without OSA from the University of Ottawa. While lying on a bed, participants were given a meal after which they were exposed for 6 hours to normoxia or intermittent hypoxia corresponding to moderate OSA, e.g. 15 hypoxic events per hour. Blood lipid levels were measured hourly.  Results: Plasma TG levels increased over time in both experimental conditions and tended to be greater under 6-h exposure to intermittent hypoxia (p=0.093, effect size ηp2= 0.383.). This trend toward higher total plasma TG under intermittent hypoxia was attributable to increased levels in denser TG carrying lipoproteins such as VLDL and CM remnants (p= 0.009, ηp2 = 0.173).  Conclusion: Acute intermittent hypoxia, a simulating model of obstructive sleep apnea, tends to negatively affect postprandial TG levels, which is attributable to an increase in denser TG carrying lipoprotein levels such as VLDL and CM remnants. These results lend support to the increase in blood lipid levels in animal studies observing the effect of acute hypoxia in mice.  Contribution to advancement of knowledge: This proposed research will allow a better understanding of the mechanisms by which obstructive sleep apnea may alter blood lipid profile. This information will be beneficial to the treatment of obstructive sleep apnea related dyslipidemia and contribute to reduce CVD risk in the large proportion of obstructive sleep apnea patients who are reluctant to current treatment avenues.
100

Impact of sleep-disordered breathing on glucose metabolism among individuals with a family history of diabetes: the Nagahama study / 糖尿病家族歴陽性者の睡眠呼吸障害と糖代謝の関連:ながはまスタディ

Minami, Takuma 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第23097号 / 医博第4724号 / 新制||医||1050(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 近藤 尚己, 教授 稲垣 暢也, 教授 石見 拓 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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