12 Clinical Trials for Various Conditions
Sleep at altitude is often poor. The purpose of this study is to evaluate the effects of a single dose of the opioid antagonist, naltrexone, on sleep quality and periodic breathing after rapid ascent to \~3800m altitude.
The purpose of this study is investigate the effects of two different breathing styles on postprandial vascular function and oxidative stress markers. Participants will complete 2 breathing conditions in random order.
The goal of this study is to identify if there is a significant prevalence of abnormal respiratory patterns in a sample of patients with low back pain (LBP), and if the presence of abnormal respiratory patterns are predictive of rehabilitation outcomes in this population. In addition, the investigators will assess the response to inspiratory muscle training (IMT) for a subgroup of subjects that maintain abnormal breathing patterns after 1 month of physical therapy. Patients seeking physical therapy for LBP within the Uhealth system will be recruited. The first phase of this study will be observational. A comprehensive assessment of their respiratory function will be performed at the beginning of their therapy and after 1 month of therapy. Subjects that demonstrate abnormal respiratory patterns after 1 month of therapy will be offered the opportunity to participate in the second phase of the study in which they will receive 1 month of inspiratory muscle training (IMT). The respiratory assessment will then be repeated at the end of the IMT training program.
Breathlessness is an extremely common and uncomfortable symptom that is reported in more than two-thirds of persons with tetraplegia. This disordered pulmonary function is due to respiratory muscle paralysis or to sympathetic denervation results in a restrictive impairment and airway hyperreactivity, respectively. These restrictive and obstructive dysfunctions have been associated with the symptom of breathlessness. However, mechanisms contributing to dyspnea in persons who have tetraplegia are not well understood. It has been demonstrated that persons with tetraplegia have an increased prevalence of breathlessness and may have an altered breathing pattern. The purpose of this study is to determine the breathing pattern at rest and measure the changes in breathing after a bronchodilator treatment (a medicine commonly used to treat asthma that relaxes and opens up airways). The determination of breathing pattern is done by measuring the movements in the chest wall while breathing. This design will elucidate differences in breathing patterns between those with tetraplegia and controls, as well as demonstrate the effect of bronchodilatation on motor drive and timing. Knowledge of the intraindividual variability and mean values of the components of the breathing pattern will improve our understanding of breathlessness in these individuals.
The purpose of this study is to test the hypothesis that blood pressure sensitivity to high sodium intake in healthy humans is characterized by increased urinary excretion of two endogenous sodium pump inhibitors, marinobufagenin (MBG), and ouabain-like compound (OLC). The study also tests the hypothesis that women who breathe slowly and have high resting end tidal CO2 at rest are more likely to have low plasma renin activity and sodium sensitivity of blood pressure than those who breathe more rapidly and maintain lower end tidal CO2.
Our aim in this study is to investigate the efficiency of the breathing with different breathing patterns. Ten volunteers and twenty patients having respiratory problems will be coached on their breathing through specific masks which will provide four different breathing patterns. These patterns will be 1) Breathing in through the nose only and out through the mouth only 2) Breathing in through the mouth only and out through the nose only 3) Breathing in and out through the nose only 4) Breathing in and out through the mouth only The data obtained from volunteers and patients will be compared within and between the groups.
Some babies have difficulty breathing, sucking, and swallowing at birth. The purpose of this study is to determine (before birth) the variables that will predict whether a newborn will experience these problems. Study participants will be pregnant women with a single fetus who are 18 years or older and who are scheduled to receive a standard prenatal ultrasound. Researchers will use the ultrasound to observe fetal motions associated with breathing, sucking, and swallowing on digital videotape. They will then review these tapes and take measurements that will help them document how breathing and swallowing develop.
The main purpose of this study is to determine if a drug (acetyl-cysteine or ACCY) can increase the amount of oxygen in your body at a high altitude of 11,500 feet. ACCY is approved by the Food and Drug Administration (FDA) as a treatment or antidote for Tylenol overdoses. Other forms of ACCY are also sold over-the-counter as nutritional supplements. In this study, the FDA-approved form of ACCY will be used "off-label" (meaning in a way not approved by the FDA). This study is being conducted by researchers from the United States Army Research Institute of Environmental Medicine (USARIEM). The study will take place in the Altitude Chamber located in the basement of USARIEM. A total of approximately 30 volunteers (men and women, military and civilians) will take part in the study. They can expect to be in the study for a minimum of a few hours each day for two weeks. The investigators hypothesize that ACCY will improve ventilation and oxygenation while at altitude.
The purpose of this study is to assess the feasibility and potential impact of an eight week program of meditation on expiratory time, anxiety and dyspnea in people with COPD.
Acute respiratory failure requiring support with mechanical ventilation occurs with an incidence of 77-100 per 100,000 person-years and accounts for half of all patients admitted to the intensive care unit. Major causes of acute respiratory failure include pneumonia, asthma, emphysema, and acute lung injury. These causes of acute respiratory failure may result in partial lung collapse (atelectasis), and airway narrowing (bronchoconstriction)that result in decreased oxygen levels requiring support with the ventilator. The prolonged inactivity in the supine position associated with mechanical ventilation can further result in atelectasis requiring increased oxygen supplementation through the ventilator. The current standard of care in acute respiratory failure is a strategy of mechanical ventilation using a single lung volume delivered repeatedly. However, the current standard mechanical ventilation strategy is not consistent with the variability in respiration of healthy humans and has been shown to contribute to increased lung injury in some studies. The mortality associated with acute respiratory failure is high, 30-40%. Thus, improvements in mechanical ventilation strategies that improve oxygen levels and potentially decrease further lung injury delivered by the ventilator are warranted. Recent studies by BU Professor Bela Suki and others in humans and animals with acute lung injury, bronchoconstriction, and atelectasis have shown that varying the lung volumes delivered by a ventilator significantly decreases biomarkers of lung injury, improves lung mechanics, and increases oxygenation when compared to identical mean volumes of conventional, monotonous low lung volume ventilation. Therefore, we propose a first-in-human, Phase I study to evaluate the safety of this novel mode of ventilation, Variable Ventilation, during acute respiratory failure
Patients affected with severe parenchymal pulmonary diseases, such as Chronic Obstructive Pulmonary Disease (COPD ), may experience dyspnea at rest due to increased work of breathing and reduced oxygenation. The delivery of high-flow humidified nasal oxygen (HFNC) has been shown to have a positive-end-expiratory pressure (PEEP) effect and is able to flush out CO2 from the upper airways, reducing dead space ventilation. Furthermore it has been proven to reduce the respiratory rate shortly after its initiation. These multiple actions offer the potential of changing the respiratory pattern and reducing work of breathing, improving the efficiency of breathing. In this short-term, physiological, open, randomized, cross-over pilot study the investigator swill describe the effects of varying settings of high-flow nasal oxygen on respiratory rate, tidal volume, and diaphragmatic work of breathing in patients with severe COPD. The investigators will also describe changes in gas exchange and effects on the subjects' comfort and dyspnea and the breathing responses to varying setting of CPAP in the subject population.
A multi-center, prospective, single-visit study designed to acquire physiologic pulse oximeter waveform data during standard polysomnography (PSG) studies performed at multiple different Sleep Lab Centers.