View clinical trials related to Apnea.
Filter by:After routine induction of general anaesthesia peak airway pressure (= P max) and other respiratory parameters(i.e. expiratory tidal volume, expiratory CO2) are measured with and without head support in three different head positions: neutral position, reclination of the head, a position deemed ideal by the anaesthesist; primary study goal is pmax depending on different head positions;
The aim of this clinical trial is to evaluate the effect of obstructive sleep apnea syndrome (OSAS) treatment in heart failure patients following coronary artery bypass graft (CABG) surgery or other coronary reperfusion.
Hypertension affects an estimated 60-70 million Americans, predisposing them to potentially life threatening cardiovascular complications. Resistant hypertension, defined as uncontrolled blood pressure on 3 or more different antihypertensive agents, is common, affecting 15-20% of the entire hypertensive population or an estimated 12-14 million Americans. Although associated with obesity, increasing age, black race, and chronic kidney disease, mechanisms of treatment resistance remain obscure. The investigators' laboratory identified primary aldosteronism (PA) as a common cause of treatment resistance with a prevalence of 20% among subjects with resistant hypertension. This is clinically important because recognition of PA can lead to effective treatment with use of aldosterone blockers. Obstructive sleep apnea (OSA) is strongly associated with and predicts development of hypertension as demonstrated in landmark cohort studies including the Sleep Heart Health Study and the Wisconsin Sleep Cohort Study. The investigators' laboratory has confirmed OSA to be extremely common in subjects with resistant hypertension, with a prevalence of approximately 85%. Recognizing that PA and OSA are exceptionally common in subjects with resistant hypertension, the investigators hypothesized that the 2 may be causally related. In testing this hypothesis, the investigators recently reported that plasma aldosterone levels are positively correlated with OSA severity in subjects with resistant hypertension but not in normotensive control subjects. This observation suggests that there is an important mechanistic interaction between untreated OSA and aldosterone excess in subjects with resistant hypertension. While the investigators' original hypothesis was that OSA stimulates aldosterone release, the investigators recognize that the opposite may also be true; that is, aldosterone excess in subjects with resistant hypertension worsens OSA. Distinguishing between these two possibilities has potentially far-reaching clinical implications. If the former hypothesis is true, effective treatment of OSA would be expected to suppress aldosterone release in subjects with resistant hypertension, thereby reversing the underlying cause of their treatment resistance. If the latter hypothesis is true, use of mineralocorticoid receptor antagonists would be expected to reduce OSA severity in subjects with resistant hypertension, thereby enhancing treatment of OSA. Either scenario would represent a new treatment approach for a highly prevalent and serious medical problem.
Obstructive sleep apnea and hypertension are well-known cardiovascular risk factors. Their control could reduce the burden of heart disease across populations. There are several drugs to control hypertension, but the only consistently beneficial treatment to reduce apneas is continuous positive airway pressure. The demonstration that one drug could improve sleep apnea and hypertension would support a novel approach in the treatment of both diseases. The role of fluid retention in sleep apnea is known for several decades. The role of diuretics is well established in hypertension but was never appropriately tested in sleep apnea. Besides to test the efficacy of these drugs, this study will help to understand the mechanisms that link hypertension and sleep apnea and its treatment.
The primary goal of this study is to determine the effectiveness and safety of delivering continuous negative external pressure (cNEP) to the upper airway as a means of preventing episodes of respiratory impairment (RI) such as hypoxemia, apnea and hypoventilation associated with the use of intravenous sedation in elective colonoscopy in adult patients.
Hypertension is highly prevalent in type 2 diabetic patients (NIDDM) with nephropathy, and is the single most important determinant of the rate of renal function loss. In many of these patients, hypertension is resistant to therapy. Although increased sympathetic activity is also highly prevalent in NIDDM patients with nephropathy and chronic renal insufficiency, little attention has been paid to sleep apnea as the cause of both resistant hypertension and sympathetic hyperactivity in this population. Since the prevalence of sleep apnea is increased in patients with either NIDDM, or resistant hypertension, or chronic renal insufficiency, it is almost certain that sleep apnea has a high prevalence in patients in whom all three states co-exist, i.e. NIDDM patients with nephropathy and hypertension resistant to therapy. As a consequence of undetected and untreated sleep apnea, resistant hypertension, nocturnal hypertension, and sympathetic hyperactivity likely contribute to accelerated loss of renal function and increased cardiovascular morbidity and mortality in these patients. Hypothesis: A. Sleep apnea is highly prevalent in type 2 diabetic patients with diabetic nephropathy and hypertension resistant to therapy. Treatment with nasal continuous positive airway pressure (NCPAP) will result in a decrease in blood pressure and restore normal diurnal blood pressure pattern. B. Sleep apnea-caused hypertension is mediated by sympathetic hyperactivity and increased activity of the renin-angiotensin-aldosterone system (RAAS) in type 2 diabetic patients with nephropathy. A decrease in sympathetic hyperactivity in response to NCPAP therapy will result in a decrease in plasma renin activity and plasma aldosterone concomitant with decreases in blood pressure. Randomized, double blind, parallel comparative (two groups) one center trial. Therapeutic treatment with nasal continuous positive airway pressure (NCPAP) Sub-therapeutic treatment with nasal continuous positive airway pressure
Obstructive sleep apnoea is a risk factor for ischaemic stroke. study hypothesis: In prospective study the investigators want to know how many ischaemic stroke patients have sleep apnoea and does thrombolysis play a role in severity of osa in six months follow up.
The purpose of this study is to investigate the effect of decreasing fluid overload by hemodialysis on the severity of obstructive sleep apnea, in patients with end stage chronic kidney disease on intermittent hemodialysis. It aims further to investigate the relationship between overhydration, nocturnal rostral fluid shift and the severity of sleep apnea.
The association of obstructive sleep apnea (OSA) and cardiac diastolic dysfunction have been reported, and improvement of diastolic function after continuous positive airway pressure (CPAP) in OSA patients was observed. However, more detailed analysis of diastolic function by supine bicycle exercise echocardiography is lacking. The investigators hypothesized that 3 months of CPAP therapy in OSA patients will significantly improve diastolic functional parameters measured by exercise stress echocardiography. Patients with severe OSA (Apnea-hypopnea index > 30) will be included in this study, and randomized to CPAP versus sham-CPAP group by 1:1 ratio. Supine bicycle exercise echocardiography, pulse wave velocity, 24 hours ambulatory blood pressure (BP), central BP will be checked before and after CPAP therapy and parameters will be compared.
The purpose of this study is to determine the prevalence of obstructive sleep apnea and associate it with the endothelial function behavior in patients with resistant hypertension. Two groups will be evaluate, one presenting uncontrolled high blood pressure, and other, with controlled blood pressure by drugs.