Active clinical trials for "Altitude Sickness"

The now widely used reference interval for pulse oxygen saturation of the neonate after 24 hours of birth has been developed relying on data from low altitude.It is not suitable for neonates at high altitude. At present, no reference interval has been established at high altitude, and the existing studies have many limitations. So this study was designed.

As altitude increases, the availability of oxygen in the air decreases, and just to compensate for this lack, the body increases cardiac and respiratory work and changes blood pressure. But that is not all: at altitude the body's ability to use oxygen is also limited. Thus, there is on one hand less oxygen available, and on the other a lower capacity to use it. All this generates significant alterations at the cardiovascular level, to the point of running possible risks of heart attack, stroke and acute pulmonary edema, particularly for individuals already suffering from cardiovascular disease. The availability of modern cable cars allows an increasingly large number of individuals, including sedentary people, elderly subjects, and cardiorespiratory patients, to easily and rapidly reach high-altitude locations. Data on what happens on the cardiovascular system at high altitude are relatively scarce, and most experiments in the literature are limited by low sample sizes. The primary purpose of this study is to assess the characteristics of a large population that acutely reached high altitude at Punta Helbronner (3,466 m above sea level), a location on Mont Blanc that is readily accessible by a 20-minute cableway ride from Courmayeur (Entreves station, 1,300 m, Skyway Monte Bianco). We aim to create a unique database and study correlations between altitude and cardiorespiratory parameters (heart rate, blood pressure, and Hb saturation) by collecting medical history data and biometric measurements in a very large population and to identify subjects most at risk of developing hypoxia at altitude. In a subset of subjects, differences in biometric variables after acute exposure at high altitude (in the transition between the downstream and the upstream measuring station) will be evaluated. Two biometric multiparametric recording systems (Keito K9; Keito, Barcelona, Spain) were installed at Entreves station as well as at Punta Helbronner. Keito K9 is an automatic multiparametric recoding system for measuring peripheral oxygen saturation SpO2, heart rate HR (pulse oximeter), blood pressure (BP; wrist pressure cuff, automatic), height (laser height meter), weight (scale platform), and body mass index (BMI). Once initiated by the subject with the completion of a cardiology history questionnaire (self-reported), the automated Keito K9 system provides a sequence of vocal and animated directions to guide subjects through the measurements (the subject may elect to abstain from some of the measurements). Upon completion, the system prints a summary receipt for the subject, and the measurements are transmitted through a Wi-Fi network and collected in an Excel sheet. It should be noted that all data collected will be anonymized or not traceable to the subject, through the use of a disposable identification card (for subjects who will perform both downstream and upstream measurement).

Pregnancy elicits adaptive changes in uteroplacental blood flow, which are altered at high altitude and may contribute to the observed 3-fold increase in intrauterine growth restriction (IUGR) and preeclampsia (PreE). The investigators propose to collect myometrial, cord blood, and placental tissue samples from women at high altitude (Summit County) and low altitude (Denver) in Colorado in order to determine if residence at altitude during pregnancy changes the vasoreactivity of myometrial arteries (MA). If altered MA vasoreactivity is found, further studies may be able to link these changes to the increased rates of PreE and IUGR at altitude and contribute to the understanding of these two disorders.

• The purpose of this study is to investigate which physiological process that controls normal human body homeostasis is affected by low levels of acute hypoxic exposure and whether there is a difference in those physiological processes and simulated flight performance between a rapid and ramp hypoxic exposure. To accomplish this, pilot analogs will be exposed to normoxic, simulated 8,000 ft (2438 m), simulated 12,000 ft (3658 m), and a ramp exposure breathing at simulated 8,000 ft for 5 minutes before ascending to simulated 12,000 ft while flying in a flight simulator. During the flight simulator, participants will need to accomplish three tasks: 1) Maintaining an altitude of 5,000 ft of elevation while performing a mental math test, 2) Flying the aircraft through the center of a series of 7 targets, and 3) Taking off and flying the aircraft a short distance to land on the center of an indicated target. Physiological measures of heart rate variability (HRV), blood pressure (BP), peripheral oxygen saturation (SpO2), electrodermal activity (EDA), and neck neuromuscular activity using electromyography (EMG) will be measured for this study. Along with questionnaires to assess hypoxic symptoms, simulator sickness, and self-perceived workload for each task

The overall goal of this study is to detect preclinical signs of HAPE by lung ultrasonography and evaluate the effectiveness of acetazolamide at decreasing pulmonary edema by using ultrasound.

Hypoxic Challenge Testing (HCT) is the recommended method for inflight hypoxia risk assessment. Onboard oxygen administration remains controversial. The Federal Aviation Administration approved portable oxygen concentrators (POCs) for onboard oxygen supply but there is lack of evidence about the use, especially in children. The aim of our study is to establish the effectiveness and safety of POCs in infants undergoing HCT.

More than 70% of visitors to high altitude suffer poor sleep. The present study seeks to answer the question: Which medication is associated with better sleep at high altitude: temazepam or acetazolamide? The investigators hypothesis is that one medication will be associated with higher subjective sleep scores than the other. The study will compare the sleep quality of 100 subjects as they take either temazepam or acetazolamide during a visit to high altitude.

Acute mountain sickness (AMS) is one of three syndromes of altitude illness. It is very common when people venture over 2500 meters altitude. This illness is mainly induced by acute exposure to low partial pressure of oxygen at high altitude that will cause a pathological effect on humans. T89 capsule is a modernized industrialized traditional Chinese herbal medicine. It is a botanical drug for oral use. In recent years, several literatures and clinical studies have showed that oral administration of T89 may provide substantial benefits in the prevention or alleviation of symptoms associated with acute mountain sickness (AMS), including nausea, vomiting, headache, dizziness, fatigue, and sleep disturbance. Such effect was also observed in a pilot clinical study recently conducted in Tibet in China. This study is a prospective, double-blind, randomized, placebo-controlled phase 2 clinical trial having three arms including T89 low-dose, T89 high-dose and a placebo controlled group. People will be screened against the inclusion/exclusion criteria after informed consent signed. Eligible subjects will be randomly assigned into one of three arms and instructed to use T89 orally twice daily for 14 days (Days 1-14) before ascending, and 5 days after ascending during the observation period (Days 15-19). The primary efficacy parameter is Lake Louise Scoring System (LLSS) which will be evaluated by subject-self and principal investigator in clinic.

This is a phase 4, randomized, double-blinded interventional trial comparing alternative doses of Acetazolamide for the prevention of High Altitude Illness.

This study is aimed to assess the efficacy of combined treatment with two antihypertensive agents (telmisartan and nifedipine) in subjects with mild hypertension exposed to high altitude.