View clinical trials related to Hypercapnia.
Filter by:The aim of the project is to evaluate the effect of hypercapnia on physiological parameters in a healthy person during short-term hypoxia and hypercapnia.
The aim of the project is to experimentally determine the effect of the choice of finger for the placement of a pulse oximeter sensor on the results of measuring peripheral blood oxygen saturation (SpO2) in a healthy person with short-term hypoxia and hypercapnia.
The purpose of this research study is to better understand how blood flow and metabolism are different between normal controls and patients with disease. The investigators will examine brain blood flow and metabolism using magnetic resonance imaging (MRI). The brain's blood vessels expand and constrict to regulate blood flow based on the brain's needs. The amount of expanding and contracting the blood vessels can do varies by age. The brain's blood flow changes in small ways during everyday activities, such as normal brain growth, exercise, or deep concentration. Significant illness or physiologic stress may increase the brain's metabolic demand or cause other bigger changes in blood flow. If blood vessels are not able to expand to give more blood flow when metabolic demand is high, the brain may not get all of the oxygen it needs. In less extreme circumstances, not having as much oxygen as it wants may cause the brain to grow and develop more slowly than it should. One way to test the ability of the blood vessels to expand is by measuring blood flow while breathing in carbon dioxide (CO2). CO2 causes blood vessels in the brain to dilate without increasing brain metabolism. The study team will use a special mask to control the amount of oxygen and carbon dioxide patients breath in so that we can study how their brain reacts to these changes. This device designed to simulate carbon dioxide levels achieved by a breath-hold and target the concentration of carbon dioxide in the blood in breathing patients. The device captures exhaled gas and provides an admixture of fresh gas and neutral/expired gas to target different carbon dioxide levels while maintaining a fixed oxygen level. The study team will obtain MRI images of the brain while the subjects are breathing air controlled by the device.
Permissive hypercapnia increased the survival rate in patients with acute respiratory distress syndrome (ARDS) who required mechanical ventilation in critical care medicine. This has been explained by its association with ventilator induced lung injury. Since then, a protective lung ventilation strategy has been very important, with a low tidal volume of 4-6 ml/kg. Patients undergoing surgery will inevitably require mechanical ventilation. In particular, patients undergoing one lung ventilation for thoracic surgery may have increased airway pressure and a greater chance of ventilator induced lung injury. Recently, protective lung ventilation has been applied to patients undergoing one ung ventilation during thoracic surgery. The purpose of this study is to evaluate the difference in the degree of pulmonary oxygenation and the incidence of postoperative pulmonary complications in hypercapnia induced by controlling the respiratory rate with a constant tidal volume.