View clinical trials related to Apnea.
Filter by:The investigators hypothesize that obstructive sleep apnea (OSA) contributes to impaired glucose homeostasis and associated vasculopathy, and nCPAP treatment of OSA should improve glycemic control and vascular function in OSA patients with type II diabetes mellitus. This study aims to investigate the therapeutic effects of nCPAP on glycemic control and vascular function in patients with OSA and type II diabetes mellitus.
Obstructive Sleep Apnea Syndrome (OSAS) is a common condition that leads to daytime sleepiness and loss of vigilance and, in addition, increased risk of cardiovascular events. The most effective treatment consists in ventilation by mask with continuous positive airway pressure (CPAP), that prevents collapse of the upper airway. However the degree of collapsibility of the pharynx may vary in relation to position, sleep stage, or alcohol or sedative consumption. Thus, CPAP treatment (invented in 1981) has evolved with the development of more sophisticated equipment that permits adapted variations in pressure levels (autoCPAP) with the objective adjusted pressure to avoid airways obstruction with minimal pressure. Different models of autoCPAP function with different signals and event detection algorithms with different modes of reaction to events. These machines are marketed with CE certification, that guarantees electrical security, but there is to date, no requirement for pre-marketing clinical validation. Nonetheless inadequate treatment may leave patients at risk of accidents and cardiovascular events. These machines can be bench tested using test equipment that can measure with accuracy the response to simulated events, but the testing equipment cannot simulate the diversity of clinical situations, nor the residual level of microarousals that may persist. Thus these bench tests need to be supplemented by clinical studies. The investigators objective is to test the efficacy of these machines on residual sleep-related events during a one night autotitration polysomnography. We develop a prospective, multicentre, non randomised study with autotitration polysomnography only for one night. These clinical results will be compared with the results of bench tests in order to evaluate the pertinence of the bench tests and their eventual utility to simplify clinical evaluation. The perspective of developing a reliable testing protocol may eventually play a role in the certification of these machines.
The study hypothesis is that the prevalence of obstructive sleep apnea in patients presenting for total knee or total hip arthroplasty is higher than generally suspected. The study will include just one arm and results will be compared to a literature control group. Participants referred for preoperative evaluation will be screened using a standard questionnaire. Those at high risk of obstructive sleep apnea will then undergo a formal overnight sleep study (polysomnography).
The purpose of this study is to compare the treatment adherence and effects in three modalities of Continuous Positive Airway Pressure Treatment for Obstructive Sleep Apnea.
Ventilation during basic life support improves survival in cardiac arrest patients significantly. Unfortunately, this is in contrast to the willingness of potential rescuers to perform mouth-to-mouth ventilation. For example, although healthcare professionals would perform mouth-to-mouth ventilation on a 4-year old drowned child in >90% of cases, this likelihood would decrease to ~10% in the case of a young male unconscious patient in a San Francisco public bus. Possibly, lay rescuers would perform assisted ventilation more often if a simple ventilation device were available. However, both the willingness to perform assisted ventilation plus the ability to open and to maintain the airway patent are necessary to ensure efficient ventilation in an unconscious patient with an unprotected upper airway. Since retention of skills after basic life support classes are notoriously low, a resuscitation tool should incorporate self-explanatory features to improve applicability, and to provide built-in safety. Thus, an option could be to ensure an open airway by the use of a built-in indicator within a ventilating device to confirm correct head extension. One possible approach may be to determine head position angles that make an open airway likely, and integrate these angles into a scale on a ventilating device; however, safe head extension needs to be determined first to prevent harm. The purpose of this study is to determine head position angles and ventilation parameters reflecting neutral position, maximal extension and a position deemed optimal by an anaesthesiologist in patients undergoing anaesthesia induction for elective surgery in a first step to design a ventilating device to optimise ventilation of an unprotected upper airway. The investigators will ventilate 30 patients with a pillow under the head simulating ventilation in the operating theater, and 30 patients without a pillow under the head simulating ventilation during cardiopulmonary resuscitation. Dentures will not be removed during assessment. After anaesthesia induction the head will be consecutively flexed in the three positions and measurements performed. Afterwards, general anaesthesia and surgery will ensue. The health risk for this extra minutes of mask ventilation is minimal. The null hypothesis is that there will be no differences in head position angles and ventilation parameters.
The purpose of this study is to determine the effects of CPAP treatment on blood pressure in patients with sleep apnea syndrome (SAS) and refractory arterial hypertension (RAH). Also, some of the mechanisms mediating SAS and RAH (systemic inflammation, oxidative stress, sympathetic hyperactivity) will be analyzed.
Sleep apnea is a common sleep disorder characterized by temporary stops in breathing during sleep and has been associated with the development of cardiovascular disease. This research will investigate one potential mechanism leading to the development of cardiovascular disorder, specifically, the blockage of blood vessels called "vascular occlusion", in subjects with sleep apnea. A group of healthy controls will be used for comparison. All subjects will undergo clinical evaluation followed by an overnight sleep study and a morning blood draw. Subjects with sleep apnea will be treated according to standard clinical management and followed under the research protocol for one month. At the end of one month, a repeat blood draw will be performed on the sleep apnea subjects for comparative analysis. If a control subject is found to have any abnormality during this research study, he or she will be referred for further clinical evaluation.
Sleep Apnea is a prevalent condition that has been increasingly diagnosed in the adult population and is now considered an independent risk factor for the development of cardiovascular disease. A better understanding of the mechanisms associated with the development of cardiovascular disease in sleep apnea is needed. This research will investigate the function of the adenosine deaminase (ADA) in subjects with sleep disorders. This enzyme is responsible for metabolizing adenosine, a neuromodulator that is released during periods of sleep apnea and that has been found to promote vascular thrombosis. There are multiple types of ADA that are genetically determined and have different levels of function. Those different forms of this enzyme may determine groups that are more susceptible to the development of thrombosis. Given the known association between sleep apnea and thrombosis, this study will determine if polymorphisms of this enzyme are differentially found in subjects with sleep apnea as compared to other sleep disturbances. The overall objective of this experiment is to assess the presence of ADA polymorphisms in sleep apnea.
Objective: Untreated OSA is associated with three fold risk of fetal and non-fetal cardiovascular events than control subjects in the long-term follow up. However, the prevalence rate and impact of OSA in patients with acute myocardial infarction (AMI) was not clear so far. The conflicts of studies come from variable period of AMI, heart function at enrollment, techniques used to diagnose OSA, time to revascularization, and target endpoint. Therefore, this project aimed to study the patients of first-time, Killip I-II, and post primary percutaneous coronary intervention (PCI) AMI in both and chronic phase to achieve four goals: Aim 1. To determine the prevalence rate of OSA in patients with first-time AMI The acute phase of AMI was defined as within 14 days of the onset of AMI and the chronic phase was defined as > 14 days of onset. Eligible patients were screened with polysomnography within 5th to 7th days and 6th months of AMI to determine the prevalence rate of OSA in the AMI. Patients who had AHI more than 15/hr were considered as suffering from OSA. Aim 2. To identify the clinical characteristics and risk factors in AMI patients associated with OSA Patients were followed up at clinics for five years. The baseline demographics of patients with or without OSA were compared to determine the factors associated with OSA in AMI patients. Aim 3. To study the impact of OSA on the prognosis of AMI patients after revascularizaton The primary endpoint was mortality rate and cardiac events. The secondary endpoint was left ventricular function and variables related to cardiovascular disease (CVD) and metabolic syndrome. The impact of OSA on AMI was determined by comparing primary and secondary endpoint between AMI patients with and without OSA. Aim 4. To identify the clinical and molecular factors attributing to AMI in OSA patients Factors attributing to AMI in OSA patients were determined by comparing the clinical data and mRNA expression of angiogenesis and other related genes in OSA patients with the acute phase of AMI and patients without major CVD.
The purpose of this study is to compare a modified AutoSet algorithm running on research hardware versus the traditional AutoSet algorithm running on an S7 AutoSet Spirit. The study will determine if the modified AutoSet algorithm reacts appropriately to obstructive apnoeas and hypopnoeas and provides suitable levels of positive airway pressure compared to the S7 AutoSet Spirit. The hypothesis is that the modified AutoSet algorithm will be more efficacious than the traditional AutoSet algorithm