The Pre-acclimatization Augmented Extreme Altitude Expedition
Altitude HypoxiaPerfusion; ComplicationsThe aim of this study is to investigate the effect of pre-acclimatization in a nitrogen tent at home, ventilated with a slightly increased nitrogen percentage, in preparation for an expedition at extreme altitude. Specifically, the current study aims to gather knowledge, whether pre-acclimatization, first, leads to improved capillary function during an expedition to extreme altitude, and second, affects incidence of altitude sickness and the likelihood of reaching the expedition destination without oxygen supplementation. The project will be carried out in two phases corresponding to two randomized controlled trials in healthy volunteers, who are participating in an expedition at extreme altitudes with or without pre-acclimatization.
Measurement of Head and Neck Tumor Hypoxia With PET-MRI
Head and Neck CancerThis study is designed to evaluate the performance of advanced magnetic resonance (MR) imaging in the assessment of tumor hypoxia using [18F]EF5 positron emission tomography (PET) as a reference in head and neck cancer patients. Low oxygen level or hypoxia contributes to radiotherapy resistance. Therefore, a clinically applicable method to detect tumor hypoxia is of great importance.
Prevention of Perioperative Pulmonary Complications by Lung Recruitment During Laparoscopic Surgery...
Perioperative ComplicationHypoxiaPerioperative pulmonary complications such as atelectasis, hypoxemia, and pneumonia after ventilatory management during general anesthesia have a negative impact on patient outcomes. The possibility of reducing perioperative pulmonary complications by lung recruitment, which uses positive pressure to prevent alveolar collapse, has been reported. Although laparoscopic surgery, which has been widely performed in recent years, can reduce the invasiveness of the operation, it is prone to alveolar collapse due to increased abdominal pressure and diaphragm elevation. The purpose of this study is to verify whether the lung recruitment during laparoscopic surgery in Trendelenburg head-down position prevents hypoxemia due to lung collapse.
Nasal Mask Kit in Gastrointestinal Endoscopy
HypoxiaGastric Cancer4 moreHypoxia is the most common adverse event in gastrointestinal endoscopes sedated with propofol. The nasal mask oxygen kit has good sealing to ensure an adequate oxygen supply and is convenient and economical.The aim of this randomized study was to determine whether the nasal mask oxygen kit reduces the incidence of hypoxia in gastrointestinal endoscopes procedures.
Delineating Between Pathophysiologic Phenotypes of Hypoxic Ischemic Brain Injury After Cardiac Arrest...
Hypoxia-IschemiaBrainThe main outcome determinant following cardiac arrest is hypoxic ischemic brain injury. Management has involved increasing the delivery of oxygen to the brain. This logic assumes that oxygen transport from blood into the brain is normal. We have demonstrated that this assumption is not true. A large proportion of post-cardiac arrest patients demonstrate an inability to unload oxygen into the brain. The mechanisms explaining this observation are unclear. This project involves using a series of evaluations to differentiate post-cardiac arrest patients who exhibit normal and abnormal oxygen transport dynamics and also investigate the underlying mechanisms for abnormal oxygen transport.
Image-Based, In-Vivo Assessment of Tumor Hypoxia to Guide Hypoxia-Driven Adaptive Radiation Therapy...
Head and Neck Squamous Cell CarcinomaBrain MetastasesThis study will apply novel MRI approaches with established sensitivity to tissue oxygen consumption and perfusion to predict hypoxia-associated radiation resistance, manifested as tumor recurrence and progression post-treatment.
The Effect of Womb Recordings on Maturation of Respiratory Control in Preterm Infants
Apnea of PrematurityIntermittent Hypoxemia1 moreThe aim of this proposal is to characterize the acute effect of early postnatal sound exposure on neuronal maturation of the respiratory control regions of the brain in preterm infants.
Multisite Tissue Oxygenation Guided Perioperative Care in Cardiac Surgery
Brain Ischemia HypoxiaMuscle; Ischemic1 moreThe BOTTOMLINE-CS trial is an international, open, single-center, pragmatic, randomised controlled trial to investigate whether multisite tissue oxygen saturation monitoring-guided perioperative care reduces composite complications within 30 days of randomization in off-pump coronary artery bypass grafting.
Effect of Hypoxic Conditioning on Cerebrovascular Health in the Elderly
HypoxiaCerebral Hypoxia5 moreIn line with the ever-growing aging of Western populations, the development of preventive strategies to slow down the effects of aging on cardiovascular health represents a major challenge in order to preserve functional capacities and a sufficient quality of life in the elderly. The alteration of vascular function (at the cerebral and systemic level) with aging is an important feature in the clinical picture including a decrease in physical and cognitive capacities. Although physical activity is recognized as an essential means of combating the effects of aging, optimizing its effects by defining the most effective strategies of practice remains a key objective. Offering alternative interventions to exercise training is also necessary for people who are unwilling or unable to engage in a physical activity program. In this context, hypoxic conditioning, alone or in conjunction with rehabilitative exercise training, is a new therapeutic modality with strong preclinical validity, in particular from a cardiovascular standpoint, and used in other pathologies to improve cardiovascular function and exercise performance and quality of life. Our aim is, therefore, to investigate the effect of hypoxic conditioning (alone or in conjunction with exercise training) on cerebrovascular health in the elderly.
Maternal Oxygen Supplementation for Intrauterine Resuscitation
Fetal DistressFetal Hypoxia1 moreMore than 80% of the 3 million women who labor and deliver each year in the United States undergo continuous electronic fetal monitoring (EFM) during labor in order to fetal hypoxia and prevent the transition to acidemia, expedited operative delivery, and/or neonatal morbidity. Category II EFM is the most commonly observed group of fetal heart rate features in labor. One common response to Category II EFM is maternal oxygen (O2) supplementation. The theoretic rationale for O2 administration is that it increases O2 transfer to a hypoxic fetus. There are conflicting national guidelines regarding O2 administration - the American College of Obstetricians and Gynecologists suggest O2 is ineffective, whereas the Association of Women's Health, Obstetric, and Neonatal Nurses recommend continued use given lack of definitive data on safety and efficacy. A recent national survey of nearly 600 Labor & Delivery providers in February 2022 revealed that 49% still use O2 . Thus, there remains equipoise on the topic and high-quality data on the safety of intrapartum O2 is needed. None of the trials to date have studied the effect of intrapartum O2 on important clinical measures of neonatal or maternal morbidity. This safety data is imperative because the field of obstetrics must hold supplemental O2 to the same rigorous standards applied to any drug used in pregnancy. Without data on these definitive outcomes, it will be challenging to implement evidence-based recommendations for supplemental O2 use on Labor & Delivery. The investigators will conduct a large, multicenter, randomized noninferiority trial of O2 supplementation versus room air in patients with Category II EFM in labor.