Active clinical trials for "Apnea"

Former studies revealed a distinct pattern of changes in circulation during deliberate apnea. Blood pressure rises significantly often accompanied by bradycardia. Further studies confirmed a massive increase of total vascular resistance as it also happens in shock to maintain perfusion of heart, lung and brain. This study is to determine the exact alterations of the cardiac function during this reaction, show the redistribution of blood volume in apnea and evaluate possible longterm effects on the central nervous system caused by repeated apnea via magnetic resonance imaging.

The purpose of this study is to determine how satisfied patients are when undergoing an overnight polysomnogram (sleep study), what their knowledge about sleep apnea is, and what factors affect obstructive sleep apnea (OSA) treatment use.

Intrathecal morphine is commonly used as an analgesic adjunct for hip arthroplasty performed under spinal anaesthesia. Sleep apnea syndrome is a condition that affects up to 10% of the patients. Effect of intrathecal hydrophilic opioids on the frequency and duration of apneic episodes is unknown. The objective of this randomised controlled trial is to investigate the effect of intrathecal morphine and surgery on apneic episodes.

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.

The purpose of this study in patients with obstructive sleep apnoea (OSA) and concomitant patent foramen ovale (PFO) is to assess the impact of percutaneous PFO closure on nocturnal hypoxemia and apnea/hypopnea, pulmonary and systemic artery pressure, endothelial function and arterial stiffness.

The overarching goal of the research proposed here is to test the hypothesis (i) that the pathophysiological mechanisms of OSA lead to deterioration in sleep-dependent memory consolidation across memory systems, with the genetic marker APOε4 as a modulator, and (ii) that CPAP can reverse some or all of these measured memory deficits. In addition, we are exploring which aspects of OSA (e.g., changes in sleep architecture, measures of hypoxemia, or the EEG power spectrum) most likely impact sleep-dependent memory processing.To this end, we are using specific cognitive tasks for which sleep-dependent memory consolidation processes have previously been demonstrated by our group and others. In addition, we are carrying out quantitative EEG power spectral analyses, to delineate abnormal functioning of brain regions with more precision.

Obstructive Sleep Apnea (OSA) is characterized by collapse of one or more pharyngeal structures during sleep (velum, tongue base, lateral walls, epiglottis). Structure-specific therapies for OSA have emerged as alternatives to positive airway pressure (PAP). Oral appliance (OA) therapy is increasingly being indicated for OSA treatment, although a complete response occurs in approximately 50% of patients. In general, OA devices are designed to maintain the mandible and/or tongue in a protruded posture during sleep, preventing upper airway obstruction. Limited studies in awake or sedated patients have demonstrated the effects of mandibular advancement on aspects of pharyngeal structure and function. The objective of the proposed research is to fully characterize upper airway collapse in OSA patients during natural sleep and use this information to understand why some patients appear to exhibit a large improvement in pharyngeal collapsibility whereas others do not.

Obstructive sleep apnea (OSA), a condition that affects a quarter of the Western adults, triples the risk for cardiovascular diseases and increases all-cause mortality. Intermittent hypoxia (IH) during transient cessation of breathing in OSA leads to endothelial inflammation, a key step in the initiation and progression of cardiovascular disease. However, the mechanisms that mediate IH-induced endothelial inflammation remain unclear and, consequently, no targeted therapy is available for vascular manifestations of OSA. Using endothelial cells (ECs) freshly harvested from OSA patients, they study team has identified impaired complement inhibition as an initial stimulus for endothelial inflammation in IH, thereby linking for the first time complement activation to vascular risk in OSA. The investigators found that a major complement inhibitor cluster of differentiation (CD59), a plasma membrane protein that inhibits the formation of the terminal complement membrane attack complex (MAC) and protects host cells from complement injury, is internalized from the EC surface in OSA patients. Consequent MAC deposition initiates endothelial inflammation in IH. Importantly, the investigators showed that IH does not significantly affect inflammation in ECs in the absence of complement, suggesting that complement activation has an essential role in endothelial inflammation in OSA. Interestingly, internalization of CD59 in IH appears to be cholesterol-dependent and statins prevent MAC deposition on ECs in IH in a CD59-dependent manner, suggesting a novel therapeutic strategy to reduce vascular risk in OSA. This led the study team to hypothesize that IH-induced cellular cholesterol accumulation reduces complement inhibition via increased internalization of CD59 from the EC surface leading to increased MAC deposition, and that treatment of OSA with continuous positive airway pressure (CPAP) and/or statins reverses endothelial dysfunction by restoring complement inhibition.

The purpose of the study is to test the workflow of an auto-titrating mandibular positioner in its intended setting. Participants with obstructive sleep apnea will use the device to determine their eligibility for oral appliance therapy and provide feedback on usability of the device.

This is a single group, unblinded, prospective clinical study. This study seeks to understand patient diagnostic and treatment journey and positive airway pressure (PAP) therapy compliance for Verily Sleep Apnea (VSA) program/app users. Participants will enroll remotely and may undergo a home sleep test (HST). Upon confirmation of obstructive sleep apnea (OSA) and prescription of PAP therapy, the participant will begin using the VSA app to supplement PAP treatment. After 90 days of active participation, the participant will be given instructions for follow-up care, as indicated.