Obstructive Sleep Apnea (OSA) is a common respiratory disorder during sleep. Apnea is cessation of airflow to the lungs, which lasts for at least 10 seconds accompanied by more than 4% drop of the blood's Oxygen saturation. Polysomnography during the entire night is the Gold Standard diagnostic method of OSA. It's high cost and inconvenience for patients persuaded researchers to seek alternative OSA detection methods. This thesis proposes a technique for assessment of OSA during wakefulness. We recorded tracheal breath sounds of 17 non-apneic individuals and 35 people with various degrees of OSA severity in supine and upright positions during nose and mouth breathing at medium flow rate. We calculated the power spectrum, Kurtosis, and Katz fractal dimensions of the recorded signals. Then, we reduced the number of characteristic features to two. We classified the participant into severe OSA and non-OSA groups as well as non-OSA or mild vs. moderate and severe OSA groups. The results showed more than 91 and 83% accuracy; for the two types of classification. Once veri ed on a larger population, the proposed method may be used as a simple and non-invasive screening tool for assessment of OSA during wakefulness.

Thesis (M. Eng. Sc.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 1994? / Includes bibliographical references (leaves 91-93).

Thesis (M.Nurs.)--University of Hong Kong, 2008. / Includes bibliographical references (p. 112-122)

Thesis (M.S.) -- Central Connecticut State University, 2008. / Thesis advisor: Ruth Rollin. "... in partial fulfillment of the requirements for the degree of Master of Science in Biology." Includes bibliographical references (leaves 39-41). Also available via the World Wide Web.

Thesis (M. Orth.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 125-144, 225-227).

Thesis (M.Orth.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 125-144, 225-227). Also available in print.

Background: Obstructive sleep apnea (OSA) is a sleep disorder characterized by episodes of cessation of breathing (apnea) during sleep. Unfortunately, a significant number of surgical patients are unaware they are afflicted with this disorder increasing the risks of postoperative complications. The lingering effect of general anesthesia causes an increase in frequency of airway collapse, leading to longer periods of apnea. This increasingly common sleep disorder is concerning for many anesthesia providers. Purpose: The purpose of this study was to evaluate the anesthesia provider's knowledge and postoperative management of patients with suspected or diagnosed OSA. Setting: The study setting was a local urban hospital Mountain Vista Medical Center (MVMC) in Gilbert, AZ. The study included (N=7) participants, who were predominantly male (85%) and a majority of the participants were Master’s prepared (85%) anesthesia providers. Method: An online survey was disseminated to participants via email. The survey included questions regarding the anesthesia provider's knowledge and postoperative practice habits of patients with suspected or diagnosed OSA at MVMC. Results: The response rate was (24%). All the respondents acknowledged that OSA was a risk factor for postoperative complications. Over half of the respondents (85%) reported encountering postoperative complications such as desaturation and apnea in their patients with OSA. The main complication that was encountered was postoperative apnea (50%), followed by decreased in saturations (33.33%), and one respondent (16.67%) encountered re-intubation during the postoperative period. However, the most important finding of the study is that over half of the providers did not routinely include continued positive airway pressure (CPAP)/noninvasive positive pressure ventilation (NIPPV) in their postoperative management of patients with suspected or known OSA due to the time needed to initiate the therapy. Conclusion: The study illustrates that a majority of anesthesia providers at MVMC agreed OSA is a significant risk factor for postoperative complications, but time constraints limited the implementation of noninvasive ventilation (NIV) therapies. Recommended strategies would be to establish a task force to examine this barrier to therapy and develop plans to address it.

No description available.

Thesis (M. Phil.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 92-103).

Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 4 uppsatser.