Active clinical trials for "Hyperoxia"

This study is aiming at assessing the effect of inspired oxygen fraction during general anesthesia on children's lung mechanics and volume. More specifically, the temporal change in end-expiratory lung volume (EELV) and respiratory system resistance and elastance during the perioperative period will be characterized in order to define the the effect of high inspired fraction of oxygen on lung function.

The purpose of this study is to investigate the impact of supraphysiologic oxygen (hyperoxia) on myocardial function in anaesthetized patients with coronary artery disease.

Supplemental oxygen is frequently administered in acutely and critically ill patients, specifically, it is often administered in trauma patients to avoid arterial hypoxemia and tissue hypoxia. There is also an increasing focus on potentially deleterious effects of hyperoxia. Further, the hemodynamic response to hyperoxia in hypovolemia is poorly understood. The present study aims to investigate the effects of supplemental oxygen on systemic and cerebral hemodynamics in simulated hypovolemia in healthy volunteers.

The investigators will conduct a non-randomized clinical trial to examine the effect of pure oxygen breathing on the brain. The study will compare cerebral blood flow, cortical electrical activity, and cognitive performance in 32 persons during room air (21% oxygen) breathing and pure oxygen (100% oxygen) breathing. Subjects will be used as their own controls. The investigators aim to: Determine whether breathing 100% oxygen changes blood flow through the brain. The investigators will learn whether brain blood flow is increased, decreased or stays the same. Determine if changes that might occur in brain blood flow are also accompanied by changes in the brain's electrical activity (EEG). Learn whether changes in the speed at which the brain processes information (cognitive function) accompany changes in brain blood flow and electrical activity that may be seen.

The primary aim of this project is to get further knowledge on the effects of + Gz accelerations and hyperoxia on lung ventilation in humans. The secondary aim is to study lung perfusion and cardiovascular function in these conditions.

The purpose of this study is to evaluate the effectiveness of Vaporous Hyperoxia Therapy (VHT) for the treatment of Diabetic Foot Ulcers.

This study aims to determine the effect of intermittent normoxic cardiopulmonary bypass (CPB) on inflammatory response, oxidative stress and myocardial reperfusion injury in adult patients undergoing valve replacement. The investigators hypothesized that nuclear factor kappa B (NFkB) was involved in regulating gene expression of myocardial inflammatory factor.

Nearly forty years ago Berran and coworkers tested an analog oxygen controller to maintain incubator oxygen levels for infants suffering neonatal respiratory disease in order to prevent hyperoxia. There are at least three clinical issues that this technology addresses: the first is avoidance of episodic hyperoxia; the second is decreasing episodic hypoxia; and the third is lowering cumulative oxygen exposure. Clinical trials which have used target SpO2 ranging probably help improve all of these problems, but so far there have been no direct measurements of continuous arterial oxygen levels, nor clinical studies which establish the degree to which improving control over blood oxygen saturation decreases the cumulative amount of oxygen exposure. This study will address the later and is an important step in the process of incorporating closed-loop oxygen control technology as a routine standard of neonatal respiratory care. OBJECTIVES: PART 1: Test and modify the instruction set for the computerized oxygen controller to achieve a goal of less than six (6) operator required interruptions per hour for oxygen saturation deviations outside of study guidelines. PART 2: Perform a within patient cross-over trial of the computerized oxygen controller versus standard of care (the patient's care team adjusts the patient's oxygen level) and evaluate the area under the time curve for oxygen exposure between the two control methods. PART 3:(After successful completion of PART 2) Continuation of the within patient cross-over study with a randomized cross-over sequence. Studies will last 4 to 12 hours divided in two (2) equal time blocks with one cross-over to either automatic or manual control modes. Provision for up to an additional twenty (20) patients to be studied.

Oxygen supplementation in the inspired mixture is commonly used in critically ill patients and observational studies highlight that those patients remain hyperoxemic for substantial periods during Intensive Care Unit stay. However, exposure to inhaled oxygen-enriched mixtures is widely recognized as potentially harmful and cause of organ damage. Although, the specific level of arterial oxygen partial pressure (PaO2) considered harmful, or the dangerous duration of hyperoxia, is not determined yet as there are no clinical trials on humans that evaluate the appropriate percentage of oxygen considered safe to maintain an adequate tissue oxygen availability. The study is designed as a multicentre, open-label, two parallel groups, randomized superiority clinical trial. The study will involve 10 European intensive care units and will recruit adult critically ill patients requiring mechanical ventilation with an expected length of stay of more than 72 hours admitted to the Intensive Care Unit. Within the conventional group, participants will receive an inspired oxygen fraction (FiO2) aiming to maintain an oxygen saturation by pulse oximetry (SpO2) equal or major than 98 percentage, accepting an upper limit of PaO2 of 150 mmHg and a lower limit of 60 mmHg. Patients in the conservative group will receive the lowest FiO2 to maintain SpO2 between 94 and 98 percentage, or when available a PaO2 between 60 mmHg and 100 mmHg. The primary objective of this study is to verify the hypothesis that strict maintenance of normoxia improves survival in a wide population of mechanically ventilated critically ill patients compared to the application of conventional more liberal strategies of oxygen administration. Survival will be measured at Intensive Care Unit discharge. The confirmation of the efficacy of a conservative strategy for oxygen administration in reducing the mortality rate among critically ill patients will lead to a profound revision of the current clinical practice and a rationale revision of the current recommendations would be mandatory, maybe also in other clinical scenarios such as emergency departments.

During surgery high concentrations of supplementary oxygen are routinely administrated. However, there is increasing evidence of potential harm with liberal oxygen therapy. The hypothesis of the present study is that oxygen therapy adjusted to a normal arterial oxygen target is feasible and will attenuate the side effects of supplementary oxygen therapy. The study design is a before-and-after study in which 25 patients will follow the standard regime with high concentrations of oxygen therapy and 25 patients will be treated with oxygen to achieve a normal value of arterial oxygenation.