View clinical trials related to Oxygen.
Filter by:Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) allows to extend the apnoeic window in patients undergoing general anesthesia by delivering 100% of heated and humidified oxygen at 70L/min in order to maintain viable gas exchange during an extended period of cessation of spontaneous ventilation. This technique has been successfully applied in several clinical settings (induction of general anesthesia, laryngoscopy in predicted difficult airway management, and as unique airway management technique for procedural sedation or general anesthesia for brief surgical procedures). Operative hysteroscopy is a brief surgical procedure usually performed under general anesthesia with intravenous agents (propofol plus fentanyl) and positive pressure ventilation through facial or laryngeal mask. The aim of this study is to investigate the effects of THRIVE apnoeic ventilation during hysteroscopy under general anesthesia. Our primary outcome is to describe the trend of SpO2 and tcCO2 during the procedures. Secondary outcomes include description of arrhythmias requiring medical treatment, hemodynamic instability, unmanageable copious secretions, airway obstruction or inability to maintain airway patency, witnessed aspiration, airway related complications, number of airway manipulations, adverse events, assessment of postoperative dyspnoea and comfort, patient satisfaction. Women (> 18 years old and < 70 years old), ASA physical status I and II presenting for elective operative hysteroscopies will be included. A number of 30 patients was planned to target the primary outcome.
The air we breathe contains 21% of oxygen. Oxygen is vital for the cells ability to produce energy and without it we could not survive. Oxygen normally exists as a molecule consisting of two atoms, O2. It has two unpaired electrons and thus is unstable and willing to accept electrons to become stable. During the formation of ATP a transportation of electrons happens over the inner membrane of the mitochondria's. Oxygen can accept these and is thereby reduced to water. Normally about 4% is not fully reduced and instead produces superoxide. Superoxide is transformed to hydrogen peroxide by superoxide dismutase (SOD) and then into oxygen and water by catalase and glutathione peroxidase. It is also possible for hydrogen peroxide to be converted to hydroxyl radicals by Fenton reactions. All these radicals are called reactive oxygen species (ROS) and they are highly reactive and capable to induce damage to cellular components as proteins, DNA and lipids. Under normal conditions SOD, catalase and glutathione peroxidase work as anti-oxidative compounds to prevent oxidative stress and damage. However, under hyperoxic conditions these defences can be overwhelmed, resulting in the formation of excess ROS and thus oxidative damage. During general anaesthesia the use of supplemental oxygen to avoid life-threatening hypoxaemia has been common practice for many years and a fixed fraction of inspired oxygen (FiO2) ranging from 0.3 to 1.0 is often used. This lead to supranormal levels of oxygen in the lungs and most of the patients also have supranormal levels of partial pressure of arterial oxygen in their blood. This study will examine otherwise healthy ambulant patients undergoing minor orthopaedic surgery during general anaesthesia to elucidate metabolic and physiological changes caused by ventilation with FiO2 0.50 for at least 45 minutes using standard respiratory settings. Exhaled breath condensate (EBC) and arterial blood will be collected prior to and after surgery. The two EBCs and two blood samples will be stored at -80°C for analysis after all patients have been included. The metabolic changes will be measured with NMR technique and multivariate statistical analysis comparing baseline values with values obtained after oxygen exposure. Collapse of the small airways induced by anaesthesia and FiO2 will be evaluated by measuring resistance and reactance with airway oscillometry after surgery compared to a baseline measurement before surgery.
Specific and objective guidelines for choosing endobronchial tube size for main-stem intubation in pediatric patients are lacking. The objective criteria for choosing an ETT size for OLV are likely to increase the safety and success. The primary aims of this study were to define the relationship between cricoid and mainstem bronchi (right and left) in children of various ages and to determine the effects of age, height and weight.
Upon collection, human oocytes are fertilized and culture up to the blastocyst stage, followed by transfer and / or cryopreservation. Culture media systems have been developed that support each step of this process. Although these culture media systems try to mimic the natural environment, several components of the in-vivo situation are not present in today´s media. One such component is anti-oxidants that may protect embryos against damage by reactive oxygen species. This investigation aims to compare blastocyst development using 2 different types of culture media systems, one of which contains antioxidants. Patients having at least eight oocytes and meeting other inclusion criteria can be included in this investigation. It is a prospective randomized multicenter study randomly dividing oocytes into two groups and assessing parameters of embryo development from fertilization up to blastocyst formation until day six. Embryos with acceptable developmental characteristics can be transferred into the uterus or cryopreserved for later use. The investigation is designed as a superiority study comparing utilization rate of blastocysts per normally fertilized oocyte using both media systems. In patients receiving embryo transfer in the fresh treatment cycle, detection of clinical pregnancy by ultrasound after 12 weeks gestation is the final endpoint of the investigation.
Pre-oxygenation with high-flow nasal cannula oxygen has been evaluated in a limited number of studies and seems to be better than traditional preoxygenation with a tight fitting mask. Oxygenation with high-flow nasal cannula in apnea demonstrates that this could be done safely for up to 25 mins with preserved saturation. Based on this, the investigators want to evaluate whether this novel concept of preoxygenation can prolong the time to desaturation in emergency anesthesia while securing a possibly difficult airway. This may reduce the number of hypoxic events during intubation. This novel concept has already been tested in clinical practice in certain cases but not during rapid sequence induction for acute surgery. Objectives and Purpose The general purpose of this project is to compare a new preoxygenation technique based on humidified oxygen in a high-flow nasal cannula with traditional preoxygenation with a tight fitting mask during rapid sequence induction intubation with focus on gas exchange.
In patients with obstructive lung disease like asthma aerosol therapy is the most used for drug administration. A order to make better use of aerosolized drugs in asthmatic patients, studies focus on ways to optimize this administration. Objective: To evaluate the efficacy of nebulized bronchodilators carried by heliox associated with positive expiratory pressure (PEP) in lung deposition of radiation activity in adult asthmatic patients between episodes and its impact on lung function. Methods: A randomized controlled trial involving 32 with a mean age of 47.28 ± 9.67 of which 25% of the sample are male, these patients were divided into four groups: heliox + PEP, + PEP oxygen, heliox and oxygen in Regarding the anthropometric characteristics, parameters and cardiopulmonary baseline spirometry data were similar for all groups. For inhalation lung scintigraphy was used a noninvasive delivery system - orofacial mask with two unidirectional valves nontoxic - inspiratory and expiratory branch - connected to the nebulizer for radioisotopes associated with PEP of 10 cm H2O. At the end of inhalation, the images were acquired in a scintillation camera at 0, 15, 30, 45 and 60 min. In order to analyze the aerosol deposition in different lung areas were delineated regions of interest (ROIs) in the vertical - the upper, middle and bottom - and horizontal central, intermediate and peripheral. Results: The spirometric data showed an increase in the values of forced expiratory volume in one second (FEV1) predicted when compared with the heliox group + PEP (80%, p = 0.030) with PEP + O2 (65%, p = 0.030). As for CI, there was also an increase in PEP + heliox group (0.05 L, p = 0.012) compared to groups without oxygen and heliox PEP (0.03 L, 0.03 L, p = 0.012 respectively) for the total number of counts, no differences were seen between groups with heliox and oxygen with PEP PEP (482510, 577598, p = 0.262 respectively) for the total number of counts by comparing the oxygen group + PEP (577,598) with the heliox group (332,951, p = 0.004) and oxygen without PEP (409,526, p = 0.045), there was a greater number of counts in the O2 + PEP group. By analyzing the rate of pulmonary deposition (IDP) in the vertical gradient, higher deposition in the middle third (p = 0.001) when compared to upper and lower in both groups. With regard to IDPs in the horizontal gradient, there was greater deposition in the intermediate region when compared to central and peripheral (p = 0.003, 0.001 respectively) in all groups. As the penetration rate, no significant differences between groups (p = 0.726). When considering the pulmonary clearance, decreased with the number of counts over time within groups (p <0.05) but no differences between them: heliox + PEP (20.67%), PEP + oxygen (13.50%), heliox (16.27%) and oxygen (16%) - (p> 0.05). Conclusion: Although no differences in the rate of penetration and clearance of pulmonary radiation activity between groups, we noted a higher number of counts in patients who underwent nebulization with oxygen associated with PEP and a functional improvement in patients who underwent nebulization with PEP as spirometric values and CI.