Active clinical trials for "Obesity Hypoventilation Syndrome"

Patients with OHS are efficiently managed with long term home-based nocturnal noninvasive positive pressure ventilation (NIPPV). Several NIPPV devices offer the feature of automatically adjusting pressure support (and/or respiratory back-up rate) on the basis of a pre-determined "ideal tidal volume" or "ideal ventilation". However algorithms used to achieve these ideal targets are different among different commercialized devices and the relative efficacy from an algorithm compared to another remains unknown. The main objective is this study is to compare two commercialized NIPPV that have this option

Sleep Apnea Hypopnea Syndrome (OSAHS), is common in patients with OHS, compared to single Obesity Hypoventilation Syndrome (OHS) or OSAHS ,patients with both of them are more susceptible to have serious hypoxia and carbon dioxide retention during sleep, and much more likely to result in pulmonary hypertension and cor-pulmonale. At present, the most widely and valid method for these patients is the Bilevel Positive Airway Pressure (BiPAP) ventilation, while, recently, the investigators discovered a completely novel device, namely auto-trilevel Ventilator. In contrast to the traditional therapy, auto-trilevel Ventilator has a more flexible expiratory positive airway pressure (EPAP), with which it can removing residual obstructive sleep apnea hypopnea events and correcting hypercapnia without contradiction. Treated with auto-trilevel ventilator may delay the progression of disease and improve life quality. The overall purpose of this study is to determine the curative effects of auto-trilevel ventilators on patients with OHS and OSAHS.

The role of different levels of compliance and long-term effects of positive airway pressure (PAP) therapy on gas exchange, sleepiness, quality of life, depression and death rate in patients with obesity hypoventilation syndrome (OHS).

Obesity hypoventilation syndrome (OHS) is a condition that occurs in small percentage of obese people that causes high carbon dioxide and low oxygen levels in the blood. OHS is associated with respiratory failure, pulmonary hypertension, and death. The cause of OHS is unclear. Since not all obese people develop OHS, it is believed that hormone imbalances can contribute to the breathing problem. Some diets can change the body's hormones. For example, low-carbohydrate, high fat "ketogenic" diets (KD) may decrease insulin and glucose levels and increase sensitivity to other hormones. The investigators hypothesize that a KD will improve breathing in OHS patients, even in the absence of weight loss.

Obesity is an escalating issue, with an accompanying increase in referrals of patients with obesity-related respiratory failure. Currently, these patients are electively admitted to hospital for initiation of non-invasive ventilation (NIV), but it is unknown whether outpatient initiation is as effective as inpatient set-up. The investigators hypothesise that outpatient set up using an auto-titrating NIV device will be more cost effective than nurse-led inpatient titration and set-up. The investigators will undertake a multi-national, multi-centre randomised controlled trial. Subjects will be randomised to receiving usual inpatient set-up, which will include nurse-led initiation of NIV or outpatient set-up with an automated NIV device. Subjects will be stratified according to trial site, gender and previous use of NIV or continuous positive airway pressure. Assuming 10% drop out rate, a total sample of 82 patients will be required. Cost effectiveness will be evaluated using standard treatment costs and health service utilisation and using health related quality of life measures (SRI and EQ5D). Change in the severe respiratory insufficiency (SRI) questionnaire will be based on analysis of covariance (ANCOVA) adjusting for the baseline measurements between the two arms of patients.

Noninvasive ventilation (NIV) is a form of ventilation delivered by a mask and is an important mode of treatment in patients with both acute and chronic respiratory (breathing) failure. Humidification is widely accepted as an essential part of the ventilation strategy in patients receiving invasive ventilation (i.e. via a tube inserted into the mouth), but its role during NIV use is not proven. Consequently, there is a variation in practice with regard to humidification during NIV. Humidification is important in maintaining upper and lower airway mucosal function and patients requiring NIV often report symptoms, such as throat dryness, due to a lack of airway humidity. Success of NIV in the acute setting is dependent on many factors including, patient tolerance of NIV during the acute phase. In patients with chronic obstructive airways disease (COPD), poor tolerance results in NIV failure, which necessitates endotracheal intubation or treatment failure. Furthermore, invasive ventilation increases the risk of a hospital acquired pneumonia, which is associated with a worse outcome. In the long term setting of NIV use, again patients frequently report symptoms due to drying of the airways and adherence to NIV can be highly variable. Adherence in these patients is important in improving both quality and length of life. Humidification devices may be technically effective, but clinicians have concerns regarding potential negative effects of these devices. There is a requirement to evaluate the use of humidification in both the acute and long term use of NIV, particular, in terms of patient ventilator interaction, which will impact on comfort and adherence to NIV. This will effect the overall effectiveness of ventilation. The investigators propose a randomised controlled trial to investigate the effects of a humidification system during noninvasive ventilation.

Main objective: To describe clinical and functional characteristics of the obese hypoventilating patient; to study the relation between the obesity-hypoventilation syndrome (OHS) and the obstructive sleep apnea hypopnea syndrome (OSAHS). In the second stage of the study, to assess patient response to non-invasive mechanical ventilation (NIV) and continuous positive airway pressure (CPAP), and to identify predictors of unfavourable response to treatment. Methodology: Patients: Patients with obesity degree I-III, with pCO2 awake and at rest > 45 mmHg, with no underlying pulmonary or neuromuscular lung disease; two control groups, one of non-hypoventilating obese patients and the other of obese patients with OSAHS, will also be studied over the same period. Design: Prospective observational study. In the first stage anthropometric, clinical, functional and metabolic data will be recorded for the obese hypoventilating patients and the two control groups (obese patients without respiratory pathology, and obese patients with OSAHS). In the second stage patients with OHS will be divided into two subgroups: group 1: patients with polysomnography (PSG) suggestive of hypoventilation, in whom NIV treatment will be initiated; group 2: patients with PSG suggestive of OSAHS (apnea-hypopnea index >15), who will be administered CPAP. Patients will be examined one month and three months after the start of treatment. The same measurements will be carried out as at the beginning of the study, with the exception of the polysomnographic study. Nonetheless, pulse oximetry and arterial gases will be performed on waking. Expected Results: Patients with OHS may be characterized and differentiated from obese patients without associated respiratory pathology on the basis of clinical, functional and metabolic data. There is a group of patients with association between OSAHS and OHS that do not respond to treatment with CPAP, and this unfavorable response can be predicted in advance.

To evaluate a novel advanced physiological monitoring system to improve nocturnal non-invasive ventilation (NIV) in Neuromuscular disease (NMD), Chest wall disease (CWD), Chronic Obstructive Pulmonary Disease (COPD) and Obesity Hypoventilation Syndrome (OHS) patients. By enhancing sleep comfort, adherence to ventilation will increase which, in turn, will improve ventilatory failure, quality of life and reduce length of admission during initiation of therapy. We aim to incorporate this technology into routine clinical practice.

The purpose of this study is to evaluate the feasibility of using of the Average Volume Assured Pressure Support (AVAPS-AE) mode versus Continuous Positive Airway Pressure (CPAP) and bilevel pressure support ventilation (PSV) modes of ventilation in patients diagnosed with Obesity Hypoventilation syndrome (OHS). The investigators believe the use of the AVAPS-AE mode of ventilation after 6 weeks will yield daytime gas exchange values which are equivalent or no worse when compared to using CPAP and bilevel PSV modes of ventilation in the OHS population.

The purpose of this study is to analyze whether the treatment of metabolic alkalosis with acetazolamide in intubated patients with chronic obstructive pulmonary disease (COPD) or with obesity hypoventilation syndrome (OHS) reduces the length of mechanical ventilation (MV).