View clinical trials related to Hypoxia.
Filter by:This observational study will investigate whether differences in birth events and oxygen levels during the newborn period affects the brain activity of children during the middle childhood years.
This study is a randomized controlled trial comparing oxygen delivery by nasal mask with continuous positive airway pressure versus standard care (nasal cannula or standard facemask) during propofol-based sedation for gastrointestinal endoscopy procedures to reduce the incidence of hypoxia. The primary outcome will be the rate of oxygen desaturation below 90% for ≥15 seconds.
Burden: Pneumonia remains the leading infectious cause of death accounting for 920,000 children under five around the world. This means a loss of over 2,500 child lives every day, or over 100 every hour. Since 2000, the number of child deaths caused by pneumonia has decreased by 47 percent. The tremendous progress made is due in part to the rapid roll-out of vaccines, better nutrition, and improved care-seeking and treatment for symptoms. However, pneumonia hasn't declined as quickly as other diseases such as malaria (58%), HIV/AIDS (61%), and measles (85%). Knowledge gap: The Lancet Series on Childhood Pneumonia and Diarrhea has reported that case management is one of the three most effective interventions to reduce pneumonia deaths in children. It is also noted that the cost-effectiveness of these interventions in the national health system needs urgent assessment. It was suggested to find out means to reduce hospital stay without compromising the quality of care. Relevance: The main purpose of the study is to compare the efficacy of two doses of parenteral Amoxicillin plus single-dose Gentamicin compared to four doses of parenteral Ampicillin plus single-dose Gentamicin. After 72 hours of treatment injectable Amoxicillin or injection Ampicillin will be switched to or replaced by oral Amoxicillin and will be discharged with an advice to attend to Ambulatory Care Unit (ACU) to receive a once-daily dose of injection Gentamicin for a total of 5 days. It is anticipated that this modified therapy will reduce the hospitalization stay of children with severe pneumonia and would therefore be relevant in countries with the resource-poor settings. By reducing the hospitalization period, this therapy has the potentials to reduce hospital-acquired infection. Hypothesis (if any): Rate of treatment failure with two doses of injectable Amoxicillin plus single-dose Gentamicin will be no more than that of four doses of injectable Ampicillin plus single-dose Gentamicin in the management of children between 2 months to 59 months hospitalized for WHO classified severe pneumonia.
Low oxygen at altitude causes pauses in breathing during sleep, called central sleep apnea. Central sleep apnea causes repeated awakenings and poor sleep. Low oxygen itself and the induced oxidative stress can damage mental function which is likely worsened by poor sleep. Reduced mental function due to low oxygen can pose a serious danger to mountain climbers. However there is also mounting evidence that even in populations of people that live at high altitudes and are considered adapted, low oxygen contributes to reductions in learning and memory. Therefore there is a serious need for treatments which may improve sleep, control of breathing and mental function during low oxygen. Melatonin is a hormone produced in the brain during the night which regulates sleep patterns with strong antioxidant and anti-inflammatory properties. A study previously reported that melatonin taken 90 mins before bed at 4,300 m (14,200 ft) induced sleep earlier, reduced awakenings and improved mental performance the following day. However how melatonin caused these effects was not determined. Therefore this study aims to determine how melatonin effects control of breathing, sleep and mental performance during exposure to low oxygen.
During One-lung ventilation, the use of lower tidal volumes (VT) is helpful to avoid over-distension, provide sufficient oxygenation, but can result in increased atelectasis. Nevertheless, it is not known if, during one-lung ventilation with constant low VT, moderate levels of PEEP combined with lung recruitment maneuvers are superior to variable low tidal volume for intraoperative oxygenation and protection against PPCs. Aim of the study is to compare a strategy using constant tidal volume with recruitment maneuvers versus variable tidal volume with recruitment maneuvers during thoracic surgery in adults. We hypothesize that in adult, non-obese patients undergoing thoracic surgery under standardized OLV with variable tidal volumes, modearte PEEP and recruitment maneuvers as compared to constant without recruitment maneuvers prevent PPCs. Patients will be randomly assigned to one of two groups: FIX TIDAL VOLUME GROUP (Groupfix): mechanical ventilation with constant (6 ml/kgIBW) tidal volume and PEEP of 5 cmH2O with recruitment maneuvers VARIABLE TIDAL VOLUME GROUP (Groupvar): mechanical ventilation with variable (6 ml/kgIBW ± 33%) tidal volume with variable respiratory rate to maintain constant minute ventilation and PEEP of 5 cmH2O with recruitment maneuvers.
The investigators aim to measure the effect of targeting premature babies to a slightly higher oxygen saturation target range (92-97%) than routinely used, for a brief period, to plan a future larger study of the effect of this on clinical outcomes. It is still unclear exactly what levels of oxygen premature babies need - both too little or too much oxygen in the first weeks after birth may be harmful. Previous studies used saturation monitoring (SpO2), where a small probe shines light through the skin and calculates how much oxygen is carried in the blood. These studies demonstrated using an SpO2 range of 91-95% rather than 85-89% was associated with more babies surviving and fewer babies suffering from a bowel condition called necrotising enterocolitis (NEC). However, targeting oxygen higher increased the number of infants who needed treatment for an eye condition called retinopathy of prematurity (ROP). It is possible an SpO2 range higher than 91-95% would be associated with even better survival. It is also possible that a higher range might not improve survival but could increase the need for ROP treatment. Infants born at less than 29 weeks gestation, greater than 48 hours of age and receiving supplementary oxygen would be eligible for inclusion. The study is at the Royal Infirmary of Edinburgh. Total study time is 12 hours for each infant (6 hours at the standard 90-95% range used in our unit, and 6 hours at 92-97%). It is a crossover study with infants acting as their own controls. Based on previous research the investigators are confident these oxygen levels will not be dangerously high. To provide an additional measure of oxygen the investigators will also use a transcutaneous monitor for the 12 hour study period, which fastens gently to the skin and measures oxygen and carbon dioxide levels on the skin surface.
The pilot study aims to evaluate a prototype system that enables military pilots to train under conditions of orthostatic hypotension and ischemic hypoxia. Both of these phenomena are experienced by aircraft crews of mainly highly maneuverable aircraft, and their syndromes include loss of color vision, loss of peripheral vision, blackout and finally G-induced loss of consciousness (G-LOC). A motorized tilt table to generate orthostatic (ORTHO) stress combined with an automatically controlled lower body negative pressure (LBNP) chamber to extort pooling of blood in the lower extremities has been developed in order to obtain new knowledge on counteracting the above-mentioned effects and minimizing the risk of their occurrence. This will help optimize the selection procedures of candidates with the best physiological predispositions to work as military pilots. The system is equipped with modules for monitoring biomedical parameters of a subject, including cerebral oxygenation, which ensures their safety and provides a source of data for performing advanced analyses. The ORTHO-LBNP system has been subjected to comprehensive laboratory tests and after a successful testing is ready for a pilot study involving pilots and/or cadets of the Polish Air Force Academy (PAFA). It is anticipated that new indicators will be proposed to enable an objective assessment of the predispositions to pursue a military pilot career. The prototype system can be easily adaptable to the needs of clinical and sports medicine as well as rehabilitation.
The primary objective of this study is to evaluate the % oxygen saturation by pulse oximetry accuracy of a combined pulse oximetry system which consists of a Nonin sensor ), an adaptor cable, and an oximetry system during non-motion conditions.
Several projects in high altitude research in environments with a low oxygen partial pressure (hypobaric hypoxia) leading to hypoxemia showed, that cerebral perfusion and cerebral performance could be improved by adding C02 (cabon dioxide). The investigators hypothesize that adding 5% C02 to 02 (Oxygen) also under normobaric conditions increases the time until a significant cerebral hyopxia is measured by near infrared spectroscopy (NIRS) compared to the administration of 95% 02. lf this hypothesis proves to be true, this approach might be used in situations in which individuals are prone to cerebral hypoxia. In bariatric surgery, patients that experience an apnea phase are more prone to (cerebral) hypoxia due to the fact, that they have a higher body mass index (BMI) leading to a reduced functional residual capacity (FRC), which serves as the oxygen reserve in the body.
1) Oxygen Transport in Normobaric versus Hypobaric Hypoxia. 2) The purpose of this study is to examine acute responses in arterial and muscle tissue oxygenation during incremental exercise in normobaric versus hypobaric hypoxia. 3) The participants in this study will consist of 12 recreationally active males and females between the ages of 19 and 45.Recreationally active is defined as participating in moderate to vigorous physical activity for 30 minutes at least 3 days per week.4) Subjects will complete an incremental cycle test to volitional fatigue in three conditions in a randomized counter-balanced order, normobaric normoxia (20.9% O2, 730 mmHg), normobaric hypoxia (14.3% O2, 730 mmHg) and hypobaric hypoxia (20.9% O2, 530mmHg). Two of the three trials will be conducted in an environmental chamber to simulate normobaric normoxia at 350 m (elevation of Omaha, NE) and normobaric hypoxia at 3094 m (elevation of Leadville, CO). The hypobaric hypoxia trial will be conducted in Leadville, Colorado at 3094 m. Trials will be separated by at least two days. Rating of perceived exertion, heart rate, blood oxygenation, respiration rate, muscle tissue oxygenation, and whole body gases will be analyzed during the trials. 5) There is no follow-up as a part of this study.