View clinical trials related to Apnea.
Filter by:In obstructive sleep apnea (OSA), the upper airway recurrently closes during sleep. The mechanisms that lead to airway closure are not completely understood. Some studies have shown that there is progressive narrowing of the pharyngeal airway across breaths during expiration (Progressive Expiratory Narrowing, PEN) preceding an obstructive apnea. The cause of PEN is unknown. The investigators will test if lung volumes and low respiratory drive play a role in PEN.
In obstructive sleep apnea, the upper airway recurrently closes during sleep. The mechanisms that lead to airway closure are not completely understood. While the airway of some people narrows and airflow decreases during inspiration due to increasing inspiratory effort, others maintain constant airflow throughout inspiration. Airway neuromuscular reflexes may protect against airway narrowing that occurs due to increasing inspiratory effort. To test this hypothesis, the investigators will initially measure airway neuromuscular reflex and inspiratory flow and then attenuate neuromuscular reflex through topical pharyngeal anesthesia to observe the effects on inspiratory flow.
It is often clinically impossible to differentiate children with an isolated snoring from those with OSA. The diagnosis of OSA is currently based on nocturnal, laboratory-based polysomnography. This expensive examination is poorly accessible due to appointments delays at hospital. Our study is designed to compare the characteristics of a home polysomnography versus standard polysomnography for the diagnosis of pediatric OSA.
Specific aim: To test the effects of nasal expiratory positive airway pressure (EPAP) therapy on sleep apnea severity among patients with recent ischemic stroke. Hypothesis 1: Ischemic stroke patients with sleep apnea will have less severe sleep apnea, as measured by the apnea-hypopnea index (AHI), with nasal EPAP therapy compared with a control night. Hypothesis 2: Ischemic stroke patients will have higher mean levels of oxygen saturation with nasal EPAP therapy compared with a control night.
Supine positioning was reported to increase upper airway collapsibility, apnea frequency and duration. Positional therapy, designed to minimize supine sleep, was reported to be beneficial in the general sleep apnea population. As supine sleep is very common in stroke patients, positional therapy might also have therapeutic effects. Given differences between stroke patients with sleep apnea and the general sleep apnea patient, such as rolling ability, body mass index and daytime sleepiness, positional therapy results in the general population may not be applicable to the stroke patient. The effects of positional therapy in ischemic stroke patients with OSA have not been well-investigated. We therefore performed a pilot randomized, controlled, cross-over study to test the following hypotheses: (1) positional therapy reduces the amount of nocturnal supine positioning in patients with subacute ischemic stroke, and (2) severity of sleep apnea improves, as reflected by apnea-hypopnea index (AHI), during positional therapy. The tolerability of positional therapy over a 3-month period in patients with ischemic stroke was also evaluated.
study Hypothesis: We hypothesize that CPAP could effectively improve the endothelial dysfunction by anti-inflammatory effect in patients of OSA,and compare to the effect of statin.
The investigators propose to compare two different treatments, continuous positive airway pressure (CPAP) versus breathing of atmospheric pressure, in subjects with obstructive sleep apnea (OSA)recovering from weight loss surgery in the post anesthesia care unit (PACU). WE hypothesize that subjects with OSA will have a higher Apnea-Hypopnea Index (AHI) with desaturation and the investigators expect that post-operative CPAP treatment in the PACU will significantly improve the AHI and therefore improve patient safety in the PACU. The investigators also hypothesize that subjects with OSA have a greater decrease in oxygen saturation in response to opioid administration by patient-controlled opioid analgesia (PCA).
Non-inferiority hypothesis; adenotonsillotomy is equally good as adenotonsillectomy in treating obstructive sleep apnea syndrome (OSAS) in children after one, three and ten years.
The aim of this randomized, double-blinded, sham-controlled cross-over trial is to demonstrate the effectiveness of continuous transcutaneous electrical stimulation of the pharyngeal dilator muscles to reduce sleep-disordered breathing.
The purpose of this study is to check blood and urine levels to further define markers/tests in the blood and urine that would be useful in following patients with obstructive sleep apnea and then to see if by wearing CPAP every night, these markers can be reduced. This research is being done because currently there are no effective blood or urine markers to determine how well CPAP is working.