View clinical trials related to Altitude Sickness.
Filter by:Acute mountain sickness is a common ailment in people venturing over 2500 m altitude. Pilgrims to high altitudes are at an added risk since they are unaware and they gain height faster than the recommendations. Acetazolamide is the standard treatment and prophylaxis of acute mountain sickness. There are no randomized controlled trials that have studied protective effects of Acetazolamide in rapid ascent, and there are few conflicting studies regarding this matter. This study is a randomized, double blinded, placebo controlled trial of Acetazolamide versus placebo in 380 healthy individuals travelling to Gosaikunda Lake of Nepal in rates of ascent that are faster than the recommendations. Acetazolamide 125 mg twice daily and a placebo will be randomly assigned for 3 days and participants will be assessed at 3 stations. This study will undertake to establish the role of Acetazolamide in Rapid Ascent and will be the first RCT done in this issue. The investigators hypothesize that Acetazolamide 125mg twice daily given before rapid ascent to high altitude in Nepalese pilgrims will not be superior to placebo in decreasing both the incidence and severity of acute mountain sickness.
The main purpose of this study is to determine if a drug (acetyl-cysteine or ACCY) can increase the amount of oxygen in your body at a high altitude of 11,500 feet. ACCY is approved by the Food and Drug Administration (FDA) as a treatment or antidote for Tylenol overdoses. Other forms of ACCY are also sold over-the-counter as nutritional supplements. In this study, the FDA-approved form of ACCY will be used "off-label" (meaning in a way not approved by the FDA). This study is being conducted by researchers from the United States Army Research Institute of Environmental Medicine (USARIEM). The study will take place in the Altitude Chamber located in the basement of USARIEM. A total of approximately 30 volunteers (men and women, military and civilians) will take part in the study. They can expect to be in the study for a minimum of a few hours each day for two weeks. The investigators hypothesize that ACCY will improve ventilation and oxygenation while at altitude.
Chronic mountain sickness is characterized by excessive red blood cell production which causes sludging of the vascular system. This high viscosity blood causes heart failure, cognitive dysfunction, and strokes. The investigators hypothesize that cobalt which has been previously been shown to be an environmental pollutant worsens the overproduction of red blood cells. The investigators plan to conduct a 6 week trial in which acetazolamide (already shown to improve chronic mountain sickness) and N-acetylcysteine (a drug that removes cobalt from the blood) are evaluated in their potential to improve chronic mountain sickness.
Diseases associated with chronic hypoxemia like chronic obstructive pulmonary disease (COPD) or emphysema, represent major medical and socio-economical problems and one of the leading cause of morbidity and mortality in the western countries. Recently, is has been shown that cardiovascular (CV) diseases contribute highly to the morbidity and mortality of these patients. Furthermore, increasing evidence suggest that systemic vascular dysfunction play a central role in the mediation of the increased CV risk in patients with COPD. However the underlying mechanisms of vascular dysfunction in these patients are incompletely understood. Chronic mountain sickness (CMS) is characterized by chronic hypoxemia related at least in part to hypoventilation; it affects relatively young adults, and may therefore allow to study the effects of chronic hypoxemia. The investigators therefore will assess systemic vascular function and test the hypothesis that increased oxidative stress is responsible for this dysfunction. Since polyglobulia is a hallmark of chronic hypoxemia and has been suggested to affect vascular function, the investigators will test the effects of hemodilution on vascular function. Then, the investigators will test the effects of acute oxygen application and 1 month antioxidative dietary supplement on vascular function. Preliminary data suggest that offspring of CMS patients may display pulmonary and systemic vascular dysfunction. Antioxidant administration is know to improve vascular function. We will test the acute effect of Vitamin C in this setting. Finally, since there is considerable inter-individual variability of pulmonary artery pressure among CMS patients and the presence of a patent foramen ovale (PFO)is increased in clinical conditions associated with pulmonary hypertension and hypoxemia, we will assess the prevalence of PFO in healthy high altitude dwellers and in CMS patients and its effects on pulmonary artery pressure at rest and during mild exercise.
This is a research study on Altitude Illness. From the information collected and studied in this project we hope to learn more about Altitude Illness, including factors that may affect and prevent the development and progression of this condition. We hope to learn if the commonly used non-steroidal anti-inflammatory medication, ibuprofen can prevent altitude illness. Possible participants in this study are healthy adults who indicated they would like to participate, learn about altitude illness, and desire to hike Barcroft Peak. Stanford University researchers hope to enroll about 100 participants.
To evaluate the additive value of tadalafil given together with Diamox (acetazolamide) in preventing acute mountain sickness in travelers to high altitude areas.
The study hypothesis is that body iron levels are important in determining the increase in lung blood pressure that occurs in response to low oxygen levels. The purpose of this study is to determine whether this is true at high altitude, where oxygen levels are low.
Some studies suggest that high-altitude related illnesses - like acute mountain sickness - could be prevented by acclimatisation, reached at low altitude using training in simulated altitude. The purpose of this study is to determine whether training in hypoxia is suitable to prevent acute mountain sickness.
Acute mountain sickness (AMS), high altitude pulmonary edema (HAPE), and high altitude cerebral edema (HACE) are complications of rapid ascent to high altitude. Several features suggest that raised intracranial pressure (ICP) may be an important factor in the pathogenesis of AMS. Magnetic resonance imaging of HACE patients has demonstrated that the oedema in HACE is of the vasogenic, rather that cytotoxic, type. Thus it is likely that cerebrovascular permeability has an important role in the development of AMS and HACE. Reactive oxygen species (ROS) have been shown to alter the permeability of the blood-brain barrier in severe ischaemia, causing vasogenic cerebral oedema. Endogenous antioxidant systems may have some capacity to respond to oxidative stress in hypoxia. The plasma concentration of urate, a powerful endogenous antioxidant, rises on acute exposure to high altitude and may play a crucial antioxidant role in systemic hypoxia. This antioxidant prevents free-radical induced cerebral oedema in animal models. There are numerous sources of ROS in hypoxia, including the mitochondrial electron transfer chain, haemoglobin (Hb) autoxidation and xanthine oxidase activity. There have been several reports of raised markers of oxidative stress in humans at moderate altitude (<3000m). Oral antioxidant supplementation with preparations containing vitamins C and E in humans at altitude has been shown to decrease breath pentanes (a marker of oxidative stress), and improve erythrocyte filterability. In a small randomised controlled trial, Bailey and Davies demonstrated a significant reduction in symptoms of AMS in subjects taking an oral antioxidant cocktail. The antioxidants alpha-lipoic acid, vitamin C and vitamin E act synergistically to provide membrane protection from free radical damage, and may protect against hypoxia-induced vascular leakage. We hypothesised that this combination of antioxidants would reduce the severity of acute mountain sickness, and reduce pulmonary artery pressures, in healthy lowlanders acutely exposed to high altitude.
The purpose of this study is to determine whether regular oral use of sildenafil citrate can prevent or attenuate high altitude illnesses.