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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.
81

A pulse oximetry based method for detection of Obstructive Sleep Apnea

han, Wang-hsiao 17 July 2006 (has links)
SAS has became an increasingly important public-health problem since 1970. It can adversely affect neurocognitive, cardiovascular, respiratory diseases and can also cause behavior disorder. Moreover, up to 90% of these cases are obstructive sleep apnea (OSA). Presently, Polysomnography is considered as the gold standard for diagnosing sleep apnea syndrome (SAS). However, Polysomnography-based sleep studies are expensive and time-consuming because they require overnight evaluation in sleep laboratories with dedicated systems and attending personnel. In this study, based on the nocturnal oxygen saturation (SpO2) signals, this work develops a method to classify patients with different levels of respiratory disturbance index (RDI) values. To achieve this goal, this study uses neural network in conjunction with different sets of feature variables to perform classification.
82

Applications of biological features for medical diagnostic problems-taking oxyhemoglobin and fingerprints as examples

Lin, Chen-liang 20 July 2008 (has links)
The physiological signals of human are very important for the diagnosis of diseases. There are two different applications of physiological signals in this study. One is using oxyhemoglobin saturation to diagnose the obstructive sleep apnea hypopnea syndrome (OSAS); the other is to determine the association between dermatoglyphics and schizophrenia by using fingerprint asymmetry measures. The objective of the first part is to comprehensively evaluate the capablity and reliability of the previously proposed oxyhemoglobin indices derived automatically for predicting the severity of OSAS. Patients with a diagnosis of OSAS by standard polysomnography were recruited from China Medical University Hospital Sleep Center. The result revealed that when AHI cutoff value was set to 30/h, ODI achieves 87.8% sensitivity and 96.6% specificity. Another important finding is that, for both apnea and hypopnea, probability of oxyhemoglobin desaturation increases with increases of body mass index (BMI) and neck circumference (NC). Early detection and intervention strategies for schizophrenia are receiving increasingly more attention. Dermatoglyphic patterns have been hypothesized to be indirect measures for early abnormal developmental processes that can lead to later psychiatric disorders such as schizophrenia. However, previous results have been inconsistent in trying to establish the association between dermatoglyphics and schizophrenia. The goal of second part of this work is to try to resolve this problem by borrowing well developed techniques from the field of fingerprint matching. Fingerprint images were acquired digitally from 40 schizophrenic patients and 51 normal individuals. Based on these images, the sample means of the proposed measures consistently identified the patient group as having a higher degree of asymmetry than the control group.
83

Obstructive Sleep Apnea: Daytime Assessment And Treatment Of A Nighttime Disorder

Vranish, Jennifer R. January 2015 (has links)
Obstructive sleep apnea (OSA) is a disease characterized by nighttime airflow limitation, hypoxemia, arousal from sleep, and elevated sympathetic activity and blood pressure. With time, this nighttime dysfunction gives rise to daytime hypertension and a heightened risk for cardiovascular disease. Current treatment options for OSA are not always effective for all patients and the gold-standard intervention, continuous positive airway pressure, has discouraging compliance rates. The work set forth in this dissertation has as its focus a novel intervention for sleep apnea known as inspiratory muscle training (IMT). IMT improves respiratory function and cardiovascular health but has not been implemented previously as a treatment for OSA. As such, Study 1 implements IMT in individuals with mild and moderate OSA, with the objective of assessing the effects of training on the cardio- respiratory parameters of this disease. We randomly assigned 24 individuals with mild- moderate OSA into one of two groups: training vs. placebo, to assess the effects of 6 weeks of training on overnight polysomnography, subjective sleep quality, blood pressure, circulating inflammatory T cells, and plasma catecholamine content. Our results show IMT- related improvements in sleep quality, reduction in the number of arousals from sleep and in periodic limb movements following 6 weeks of training. Most important, IMT was associated with a significant reduction in systolic (~12 mmHg) and diastolic (~5 mmHg) blood pressure, relative to sleep apneics who undertook 6 weeks of placebo training. Additionally, individuals in the training group exhibited ~30% lower levels of sympathetic activity, as measured by plasma catecholamines, relative to placebo trained peers. The mechanism(s) that underlie the IMT-related reductions in blood pressure and sympathetic activity remain to be determined. However, in an effort to determine the precise respiratory stimulus that contributes to the results obtained in Study 1, we subsequently assessed the specific respiratory components of IMT to determine which component (large intrathoracic pressures and/or large lung volumes) likely contributes to the reduction in blood pressure in Study 1. The results of this study conducted in normotensive adults show that respiratory training that entails either large negative or positive intrathoracic pressures reduces systolic and diastolic blood pressure in healthy young adults. Importantly, neither the generation of large lung volumes alone nor performance of daily paced breathing is sufficient to lower blood pressure. Study 3 is a methodologic study that has as its focus upper airway electromyography (EMG) and the utility of assessing EMG activity across a range of conditions and breathing tasks in wakefulness. Because OSA traditionally has been viewed as the result of neuromuscular dysfunction of the upper airway that occurs during sleep, the aim of this work was to develop a "fingerprint" of healthy electromyographic activities during the day in healthy adults across a range of breathing tasks, body positions, and from two different muscle compartments of the upper airway. The findings from this study demonstrate regional differences in muscle activity that vary as a function of body position and task. These data from healthy subjects provide the basis of comparison for subsequent studies in individuals with obstructive sleep apnea.
84

Effect of Maxillomandibular Advancement Surgery on Blood Pressure in Patients with Obstructive Sleep Apnea: A Pilot Study

Bourque, Susan Elizabeth 12 December 2012 (has links)
There is evidence that non-surgical treatment of OSA improves blood pressure (BP) in patients with obstructive sleep apnea (OSA). The objective of this study is to determine the effect of maxillomandibular advancement (MMA) surgery for OSA on BP. 15 patients undergoing MMA surgery for treatment of OSA were enrolled. Ambulatory BP, and BMI were recorded pre- and post-operatively. The average age of the patients was 48.9 years and they had mean preoperative AHI of 40.8 and a mean baseline BMI of 30.8 kg/m2. There were no statistically significant reductions in mean systolic or diastolic BP postoperatively. The BMI was found to decrease on average from 30.8 kg/m2 to 29.3 kg/m2 at follow up (p = 0.01). There were no identifiable relationships between OSA severity and BP. Given the prevalence of OSA and it’s adverse medical consequences, more studies to determine the effect of MMA on BP are warranted.
85

The assessment of heart rate variability during rest, submaximal and maximal exercise in individuals at risk for obstructive sleep apnea

Mallory, Amanda L. 12 August 2011 (has links)
Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science
86

The effects of acute exercise on fibrinolysis in an at risk obstructive sleep apnea population

Vesbach, Steve J. 16 August 2011 (has links)
Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science
87

Arousal, Sleep and Cardiovascular Responses to Intermittent Hypercapnic Hypoxia in Piglets

Tinworth, Kellie January 2003 (has links)
Master of Science (Medicine) / Clinical studies have demonstrated an arousal deficit in infants suffering Obstructive Sleep Apnoea (OSA), and that treatment to alleviate the symptoms of OSA appears to reverse the deficit in arousability. Some sudden infant deaths are thought to be contingent upon such an arousal deficit. This research utilised young piglets during early postnatal development, and exposed them to intermittent hypercapnic hypoxia (IHH) as a model of clinical respiratory diseases. Arousal responses of control animals were compared to the animals exposed to IHH. Comparisons were also made between successive exposures on the first and the fourth consecutive days of IHH. Time to arouse after the onset of the respiratory stimulus, and frequency of arousals during recovery, demonstrated that arousal deficits arose after successive exposures and that these were further exacerbated on the fourth study day. After an overnight recovery period, the arousal deficit was apparently dormant, and only triggered by HH exposure. These studies confirm that both acute and chronic deficits can be induced on a background of otherwise normal postnatal development, suggesting that deficits observed in the clinical setting may be a secondary phenomenon.
88

Rhonchopathy : long-term clinical results after palatal surgery /

Lysdahl, Michael, January 2002 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 5 uppsatser.
89

Ventilation and lung volume during sleep and in obstructive sleep apnea /

Appelberg, Jonas, January 2003 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2003. / Härtill 4 uppsatser.
90

The relationships between obesity, obstructive sleep apnea, and commercial motor vehicle operator performance /

O'Neil, Jennifer Ann. January 2010 (has links)
Typescript. Includes bibliographical references (leaves xliii-xlv).

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