Active clinical trials for "Hypoxia"

This study will determine if the replacement of the measured arterial blood oxygen saturation with expired (end-tidal) oxygen value is an acceptable method to calculate the accuracy of pulse oximeters.

The purpose of the study is to determine the effect of a single exposure of intermittent hypoxia on erythropoietin levels and hemoglobin mass in young adults, older adults and patients with type 2 diabetes.

This prospective observational study will enroll 60 moderate-to-severe OSA patients (AHI≧15/hour, 30 obese [BMI>=27] & 30 non-obese [BMI<27]) and 40 age-, gender-, BMI-matched controls without OSA. Venous blood 10 ml will be collected to isolate neutrophils, which are later tested for their ability to produce neutrophil extracellular traps (NETs) under the effect of PMA (phorbol 12-myristate 13-acetate). The test will be repeated if OSA patients receive CPAP therapy (continous positive airway pressure therapy).

Obesity is characterized as a low-grade systemic inflammatory disease, which changes several pro-and anti-inflammatory cytokines. The practice of physical activity is a non-pharmacological method that results in the reduction of the systemic inflammatory state and, when associated with hypoxia exposure, may substantially improve this state. Deep-water running is highly indicated to obese for guarantee less joint impact and lower fatigue levels. In this way, the high-intensity exercise associated with intermittent recovery hypoxia in obese women will be investigated.

Spinal cord injury (SCI) interrupts descending synaptic pathways from brainstem premotor neurons to spinal motor neurons, thereby paralyzing muscles below the neurological level. In recent years, considerable evidence has demonstrated that acute intermittent hypoxia (AIH) elicits plasticity in the spinal cord and strengthens spare synaptic pathways which is expressed as respiratory and somatic functional recovery in animals and humans suffering from incomplete SCI. The fundamental hypothesis guiding this project is that AIH-induced motor plasticity can be "harnessed" to improve walking capacity in incomplete SCI patients, classified as C and D categories according to International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI). The inclusion criteria include patients > 18 years-old, with traumatic or non-traumatic, non-progressive incomplete SCI, onset > 6 months, neurological level C5-T12, with walking ability with or without assistive devices, without joint contractures, orthopedic injuries, osteoporosis, cutaneous lesions, cardiopulmonary complications and a body weight below 150 Kg. A randomized, triple-blind, placebo-controlled parallel design study will be done including 100% of patients fulfilling the criteria. Participants will receive repetitive acute intermittent hypoxia (rAIH: 15 episodes of 90 second 9% inspired oxygen interspersed with 90-second normoxia) or repetitive continued normoxia (rSham: 21% inspired oxygen) combined with 45 minutes body weight-supported treadmill training on 5 consecutive days and then three times per week for 3 weeks. Primary outcome measurement will be the 10-meter walking test. Secondary outcome measurements include the 6-minute walking test, timed up and go test, body/weight load, modified ashworth scale and visual analog scale. All outcomes will be measured before beginning the protocol (baseline), after five days of AIH/Sham (D5), weekly up to the end of the study (W2-W4), and a post-study follow-up for 2 weeks (F1-F2). Aditionally, cognitive assesment before and after the study will be performed using the "Figura compleja de Rey-Osterrieth" and the "Test de aprendizaje verbal España Complutense (TAVEC)". Repetitive AIH and body weight-supported treadmill training may represent a novel, safe, and noninvasive potential therapy to partially restore walking function in incomplete sub-acute and chronic SCI patients, a population with limited, if any, potential for improved function.

This is a Phase I, open-label, single center trial to evaluate the feasibility and safety of low concentration CO2 gas mixture (5% CO2 + 95% air) inhalation in asphyxiated, cooled, mechanically ventilated newborns at risk of hypocapnia with The hypothesis is that hypocapnia, which is driven by hyperventilation in the presence of metabolic acidosis, is deleterious to the injured brain and can be safely avoided with low concentration CO2 inhalation.

Solid tumours often have highly disorganised vasculature that results in low oxygenation. This combined with high metabolic rates leads to oxygen demand outstripping supply causing tumour hypoxia. Hypoxia drives multiple cellular processes involved in the hallmarks of cancer. Tumour hypoxia also decreases the effectiveness of anticancer treatments. This is especially true for patients treated with radiotherapy since it has been long recognised that hypoxic tumour cells require 3 times the dose of radiation to cause the same amount of cell death as cells irradiated under normal oxygen conditions. To date, the majority of attempts at overcoming tumour hypoxia have focused on increasing oxygen supply. However, such techniques have produced modest benefits at best and subsequently have not been adopted into current clinical practice. An interesting alternative approach to tackling tumour hypoxia is to decrease oxygen 'demand' by reducing tumour oxygen consumption. This strategy has been suggested to be more effective in reducing hypoxia than previous methods aimed at increasing oxygen delivery. Pre-clinical data demonstrates that the commonly prescribed anti-protozoal drug atovaquone significantly reduces oxygen consumption in a variety of tumour cell lines in vitro. This reduction in oxygen consumption leads to a profound reduction in tumour hypoxia in animal models. It is anticipated that if these effects on tumour hypoxia could be reproduced in humans, that their tumours could be rendered markedly more sensitive to radiotherapy. This window of opportunity trial will assess whether atovaquone significantly reduces tumour hypoxia in adult patients referred for surgery with suspected non-small cell lung cancer. This will be assessed using a combination of functional imaging and circulating markers of hypoxia. If atovaquone is demonstrated to result in a reduction in tumour hypoxia, larger clinical trials will be conducted to determine whether this well-tolerated and inexpensive agent improves radiotherapy efficacy and clinical outcomes.

The purpose of the present project is to compare High-Flow Nasal Oxygen therapy with Standard Oxygen therapy, initiated in the prehospital setting in patients with acute hypoxemia respiratory failure, in terms of oxygenation at arrival to the hospital and need of mechanical ventilation during the subsequent 28 days

The prevalence of pre-hypertension and hypertension in the elderly is very high. Apart from medication, physical exercise training is a potential strategy to reduce blood pressure, however, the ability to perform exercise can be limited in the elderly. Hence, alternative non-pharmacological strategies to reduce blood pressure are necessary. Two interventions that have been shown to positively influence blood pressure are respiratory muscle training (RMT) and intermittent hypoxia (IH). Whether a combination of RMT and IH yields even better effects is currently unknown. Therefore, in this study, the effect of a single session of RMT with and without IH on blood pressure and associated cardiovascular parameters will be investigated in elderly subjects with pre-hypertension.

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.