DAHANCA 30: A Randomized Non-inferiority Trial of Hypoxia-profile Guided Hypoxic Modification of...
Head and Neck Squamous Cell CarcinomaRadiotherapy4 moreHypoxic modification of radiotherapy with nimorazole has previously been shown to increase radiosensitivity in hypoxic head and neck squamous cell carcinomas (HNSCC). In Denmark, nimorazole is added the radiotherapy of most HNSCC, as it has not previously been possible to discriminate more hypoxic tumours from less hypoxic tumours. A hypoxia gene profile has shown to discriminate between responders and non-responders to nimorazole. In DAHANCA 30, expected hypoxia profile guided non-responders are randomized to +/- nimorazole during radiotherapy.This in order to verify clinical use of the gene profile in selecting the relevant patients for hypoxic modification of radiotherapy with nimorazole.
Assessing the Feasibility and Effectiveness of Introducing Pulse Oximetry in IMCI Services
Childhood PneumoniaHypoxemiaThe purpose of the study is to assess the feasibility, acceptability and operational challenges of introducing Pulse Oximeter (PO) in IMCI services to manage acute respiratory infections at first-level primary care facilities in Bangladesh (phase 1). The investigators will also evaluate the effectiveness and cost-effectiveness of introducing PO in IMCI services at first level primary care health facilities (phase 2). This study will employ a cluster randomized controlled trial design to evaluate the effectiveness of introducing PO in IMCI services (phase-2 objective). The feasibility assessment (phase-1 objective) will be nested within the larger effectiveness trail as internal piloting; which will help in generating evidence for designing a robust phase-2 trial. First-level primary healthcare facilities providing IMCI services will be regarded as clusters and the unit of randomization. Sixteen first level primary care health facilities (UH&FWC) will be randomly assigned to comparison and intervention facilities.
High Intensity Interval Training and Muscle Adaptations During PR
Pulmonary DiseaseChronic Obstructive2 morePulmonary rehabilitation (PR) is a validated treatment in patients with Chronic Obstructive Pulmonary Disease (COPD), improving exercise tolerance, quality of life and dyspnea. However, 20 to 30% of patients did not respond to PR and particularly those with chronic hypoxaemia. In most disabled patients, High Intensity Interval training (HIIT) is an alternative to perform exercise training with similar gain in exercise capacity than continuous exercise training. In patients with exercise-induced oxygen desaturation, the repetitions of hypoxia/resaturation phases during intermittent exercise could result in bursts of oxidative stress and induce positive or detrimental effect on mitochondrial function according to the importance in the oxidant stimulus. Few data have ascertained the benefit of HIIT on mitochondrial oxidative capacity (Vmax) in healthy subjects compared to continuous exercise training but no data are available in COPD patients with exercise-induced desaturation, and the change in oxidative stress in such training regimen. The investigators hypothesize that the repetitive bursts of oxidative stress and the improved antioxidant capacity in the course of the training sessions would stimulate mitochondrial adaptations to a larger extent after HIIT than continuous exercise training in severe COPD patients with hypoxemia. Moreover, they will assess the relationship between the change in oxidative stress in blood and in muscle. The clinical relevance of this study will be to ascertain the benefit and the safety of HITT in this subgroup of COPD patients in whom benefit of PR is often weak.
RIC in HIE: A Safety and Feasibility Trial
Hypoxic-Ischemic EncephalopathyRemote Ischemic Conditioning has never been studied in neonates with HIE. However, RIC has been studied in animal models of perinatal asphyxia and has shown encouraging results. In neonatal rats with HIE, RIC is associated with reduced sensory motor deficits compared to non-RIC, and repeated cycles in three consecutive days is superior to a single treatment. In piglets, four cycles of 10 minutes of bilateral hindlimb ischemia immediately after bilateral common carotid occlusion results in reduced cell death in the periventricular white matter and internal capsule. These preclinical studies support the hypothesis that RIC may be beneficial in infants with HIE.
Acute Intermittent Hypoxia in Traumatic Brain Injury
Brain InjuriesTraumaticThis study is designed to answer questions related to safety and preliminary efficacy of Acute Intermittent Hypoxia (AIH) in Traumatic Brain Injury (TBI) survivors. First, we aim to establish whether brief reductions in inhaled oxygen concentration can be safely tolerated in TBI survivors. Second, we aim to establish whether there are any effects of AIH on memory, cognition, and motor control. Participants will be monitored closely for any adverse events during these experiments. Data will be analyzed to determine if there is an improvement in key outcomes at any dose level.
A Potential Role for Oxygen in the Development of Mental Fatigue and the Subsequent Decline in Cognitive...
Mental FatigueNear Infrared Spectroscopy4 moreIntroduction Both Mental Fatigue (MF) and hypoxia impair multiple aspects of cognitive functioning. The decline in cognitive functioning in hypoxic conditions is associated with alterations in brain oxygenation and hemodynamic responses. These hemodynamic responses are preferably measured at the prefrontal cortex, an area of the brain that is known for its executive function and role in decision making, planning, attention and (short-term) memory. This study will investigate the role of prefrontal cortex oxygenation during the development of mental fatigue and during cognitive performances by altering the ambient oxygen availability through normobaric hypoxia (3800m; 12,9% O2) and normoxia. Methods Subjects will perform four trials in a sound-insulated climate chamber (20°C and 40% RH). Upon entry in the climatic chamber participants will adapt to the environment for 30 minutes. Next, they will perform a modified cognitive test battery "cognition", a fine motor task "Motor Performance Series" and a visuomotor-fitlight task before and after a 60-minute individualized Stroop task or control task (randomized. blinded, placebo controlled, counter-balanced, cross-over design). Nearinfrared spectroscopy (NIRS) will be used to assess hemodynamic changes (oxygenated hemoglobin (O2Hb), deoxygenated-hemoglobin (HHb) and total hemoglobin (tHb)) at the PFC. Hypotheses 1) MF will lead to earlier changes in the prefrontal NIRS-parameters (O2Hb, HHb, tHb) with lower oxygen availability. 2) The effects of MF on cognitive performance manifest itself to a greater extent with lower oxygen availability.3) Visuomotor performance declines to a greater extent due to MF with lower oxygen availability.
Improving Human Cerebrovascular Function Using Acute Intermittent Hypoxia
Healthy Brain PerfusionThis study uses magnetic resonance imaging to determine whether 3 weeks of repeated exposure to Acute Intermittent Hypoxia can improve brain blood flow or blood flow regulation in healthy adults.
Accuracy of Dexcom G6® and FreeStyle Libre® Sensors in Standardized Hypoxemia Conditions
Type 1 Diabetes MellitusType 2 Diabetes MellitusThe major aim is to evaluate accuracy of 2 Continuous Glucose Monitoring Systems (CGMS) : Dexcom G6® and FreeStyle Libre® in standardized hypoxemia conditions (artificial normobaric hypoxia). Our purpose is to demonstrate the good performance and calibration of these CGM sensors in hypoxemia conditions.
NIV-FOB, HFNC-FOB- Comparison of Methods
Respiratory FailureHypoxemia1 moreThe aim of the study is to asses safety and indications and contraindications for performing bronchofiberocopy (FB) with respiratory support methods, i.e. non-invasive ventilation (NIV) and high flow nasal oxygen therapy (HFNO). Additionally, researchers want to determine how using these methods could avoid the risk of most common complications such as: hypoxemia-related events, decompensation of chronic respiratory failure, worsening of gas exchange, hemodynamic instability.
American Heart Association- Stroke/Hypoxia Study
StrokeOf the 795,000 people who experience a stroke every year in the US, only a small percentage will achieve full recovery. While current therapies promote strength and endurance, none directly address the unique potential of the brain to reorganize following injury. The goal of this project is to explore the effects of a novel therapy, acute intermittent hypoxia (AIH). During this therapy, individuals receive brief bouts of reduced oxygen levels by inhalation through a face mask. (This is akin to being on top of a tall mountain). In brief exposures, AIH is known to trigger the release of specific proteins that help the brain adapt to oxygen reductions. Published results in people with incomplete spinal cord injury have shown that AIH enhances muscle strength and coordination rather quickly. The research team aims to study the effects of AIH in stroke survivors.