View clinical trials related to Altitude Sickness.
Filter by:A ketogenic diet (KD) reduces daily carbohydrates (CHOs) ingestion by replacing most calories with fat. KD is of increasing interest among athletes because it may increase their maximal oxygen uptake (VO2max), the principal performance limitation at high altitudes. The investigators examined the tolerance of a 4-week isocaloric KD (ICKD) under simulated hypoxia and the possibility of evaluating ICKD performance benefits with a maximal graded exercise bike test under hypoxia and collected data on the effect of the diet on performance markers and arterial blood gases.
This study analyses the impairment of colour vision during hypobaric hypoxia in volunteers of different groups.
A single-centered randomized doubled blinded placebo-controlled cross-over trial comparing two the effect of two carbonic anhydrase inhibitors on exercise performance in acute hypoxia. Participants will be young (under 40 years of age), healthy males and females who are regularly physically active.
The 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.
One of the most common nutritional deficiencies worldwide is iron deficiency. Iron deficiency is considered the main cause of anaemia in developing countries, including those in South America. The most recent surveys report that the prevalence of anaemia is as high as, 40 and 25% in Peru. Populations living at higher altitudes may have higher iron requirements, as body iron is naturally increased in long-term high-altitude residents to compensate for the lower oxygen in the air at high altitudes. However, the effects of chronic exposure to high altitude on iron status, body iron compartments and dietary iron requirements are incompletely understood. The primary objective of the proposed research is to determine iron bioavailability of iron from biofortified potatoes at different altitudes in populations of Andean descent. Human trials will be undertaken with volunteers in the Huancavelica region of Peru (elevation: 3676 meters) as well as in Lima (elevation close to sea level). The aim is to assess the effect of altitude on the absorption from a promising iron biofortified potato cultivar. These trials require incorporation of iron stable isotopes into the meals of the bio fortified potato and the analysis of the isotopes in subsequent blood (red blood cells) samples. Stable iron istotopes are considered the golden standard to assess human iron absorption and can be safely used as tracer substances in humans. The objective of the study is to compare, in volunteer females of childbearing age, the bioavailability of iron from bio-fortified potatoes in two locations of different altitudes and quantify the effect of altitude on iron bioavailability from a potato meal consumed over 5 consecutive days.
This study aims to compare the effect of the use of supraglottic jet oxygenation and ventilation (SJOV) with high-flow nasal oxygen therapy (HFNO) on reducing the rate of hypoxia during gastrointestinal endoscopic procedures in deeply sedated patients at high altitudes.
Pulse oximetry offers real time and non-invasive estimation of arterial oxygen saturation in a cost-effective way, and has become a critical tool in guiding the usage of supplemental oxygen in sick newborns. During postnatal transition, pulmonary pressure decreases upon the activation of the lungs, and the ductus arteriosus constricts and closes upon the increase of partial oxygen pressure, which is negatively correlated with altitude. As a result, postnatal transition may be different at high altitudes. Umbilical cord blood gas analysis is now recommended in all high-risk deliveries because of its' value in providing information about preceding fetal hypoxic stress. But there are only limited studies about the SpO2 measurements during the first few hours after birth and umbilical blood gas analysis at high altitudes, especially at altitudes above 2500m. The primary outcome of the study is to determine the reference intervals for preductal oxygen saturation during first 2 hours of life stratified by different gestational age. The secondary outcomes is to establish the pH and lactate cutoff value of umbilical arterial blood gas at different altitude level.
The purpose of this study is to investigate the impact of rapid elevation to 3,800 meters on the cognitive function of low-altitude residents through a plateau field and plain control study, and explore the objective indicators related to the impaired cognitive function.
This study aims to determine whether the use of SOJV could reduce the rate of hypoxia during gastrointestinal endoscopic procedures in deeply sedated patients sedated at high altitude comparing to the supplemental oxygen administration via nasal cannula.
In this study, the investigators will examine the extent to which having suffered coronavirus disease 2019 (COVID19) impacts one's sensibility to hypoxia by means of the 'Richalet test'. The aim of the study is to formulate recommendations for advice in altitude mountain medicine for patients having suffered COVID19. To determine any eventual changes in response to hypoxia, performances by participants having suffered COVID-19 and participants having stayed free of COVID-19 will be both compared intra-individually with previous performances (pre-COVID-19 pandemic) and between both groups of subjects. The investigators hypothesize that patients having suffered COVID19 might perform differently on the cardiopulmonary exercise test compared to before the illness. Based on recent research on COVID19 pathophysiology and -patient follow-up, it might be expected that COVID19 alters the response to hypoxia, thus influencing one's acclimatization capabilities at high altitude, albeit reversibly and/or temporarily. Different alterations of response to hypoxia could be observed. The virus causing COVID19, the "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2), has the potential to significantly damage the nervous system and to affect cardiorespiratory functions. If SARS-CoV-2 does, similarly to MERS and SARS, induce cardiorespiratory and neurological dysfunction, then COVID19 patients may have impaired hypoxia response after infection and perform worse on the 'Richalet test' in comparison to before the illness. Conversely, reports of high prevalence of dyspnea in patients up to 3 months after SARS-CoV-2 infection, might indicate infection-induced degenerative changes in the carotid bodies, which might lead to sensibilization of the peripheral chemoreceptors to impaired oxygenation. Possibly similar to the impact of aging and smoking on the cardiorespiratory response to hypoxia, this phenomenon of sensibilization could entail an increased hypoxic response in patients having suffered COVID-19. Accordingly, patients might perform better on the 'Richalet test' post-COVID-19 than they did before.