View clinical trials related to Altitude Sickness.
Filter by:Acute Mountain Sickness (AMS) is a common condition affecting individuals traveling to elevations greater than 2500 meters (8200 feet). While more gradual ascent profiles, as well as the use of acetazolamide, have been shown to decrease the incidence of AMS, it remains a common condition that can affect anyone who travels to altitude. Many pharmacologic options for treatment of AMS exist, however these are not always effective or able to be taken by all patients. Continuous positive airway pressure (CPAP) has been shown in some small studies and reports to be a potential non-pharmacologic method of both preventing and treating AMS. No large trials to validate the efficacy of CPAP in altitude related illness have been done. This study aims to evaluate the degree to which CPAP can improve symptoms of AMS, as well as improve oxygen saturation among individuals traveling in a high altitude location.
Warfighter Performance Optimization in Extreme Environments remains an area of important and intense investigation, with the following goals: (1) Optimize, sustain and augment medical readiness and physiological/ psychological performance in extreme and hazardous military operational environments and (2) develop joint DoD countermeasures and guidance to sustain performance, assess physiological status, and reduce injury risk in extreme and hazardous operational environments. Successful and safe outcomes in extreme and hazardous operational environments require that warfighters maintain optimum cognitive and exercise performance during physiologic stress. Extreme environmental conditions encountered in such environments include warfighter exposure to hypoxia and hypothermia, alone or in combination. Both hypoxia and hypothermia undermine O2 delivery system homeostasis, imposing dangerous constraints upon warfighter cognitive and exercise capacity. While red blood cells (RBCs) are commonly recognized as O2 transport agents, their function as a key signaling and control node in O2 system delivery homeostasis is newly appreciated. Through O2 content-responsive modulation of RBC energetics, biomechanics, O2 affinity and control of vasoactive effectors in plasma - RBCs coordinate stabilizing responses of the lung, heart, vascular tree and autonomic nervous system - in a fashion that maintains O2 delivery system homeostasis in the setting of either reduced O2 availability (hypobaric hypoxia) or increased O2 demand (hypothermia). Human RBCs demonstrate adaptive responses to exercise, hypoxia and hypothermia - these changes are commonly appreciated as a key element enabling high altitude adaptation. However, under conditions of hypoxia and hypothermia, without prior adaptation, RBC performance is adversely impacted and limits the dynamic range of stress adaptation for O2 delivery homeostasis - therefore limiting warfighter exercise capacity and cognitive performance in extreme environments, such as during acute mountain sickness.
The POWERbreathe™ Plus: an Inspiratory Muscle Training device (IMT) with adjustable resistance. Intervention lasts 4 weeks, with a frequency of 6 days/week, 2 series of 30 inspirations in the morning and evening. Resistance based on 60% of the Pressure Maximal Inspiratory (PMI). Progressive increase in resistance every week. Four laboratory visits: 2 pre-tests and 2 post-tests. Each pre- / post- test will go under normoxic and hypoxic conditions. Measurements include Pulmonary functions (spirometry test); blood microcirculation (vascular occlusion test); gas exchanges (e.g. VO2max), cardiac parameters, heart rate variability, maximal aerobic power (incremental and time limit test)
A multicenter, randomized controlled trial was designed to evaluate the effectiveness and safety of the comprehensive traditional Tibetan medicine program combined with remote ischemic conditioning on high altitude polycythemia.
Research Title: RISK FACTORS ASSOCIATED WITH HIGH ALTITUDE SICKNESS: A CASE-CONTROL STUDY Rationale: The Study will help us to identify risk factors of high altitude sickness among Nepalese and International patients. Aims and Objectives: - To identify risk factors for high altitude sickness, including AMS, HACE, and HAPE. - To compare the prevalence of high altitude sickness between individuals who ascended rapidly versus those who ascended slowly. - To examine the association between high altitude sickness and various demographic and environmental factors, such as age, sex, altitude, and temperature. - To evaluate the effectiveness of preventative measures, such as gradual ascent and medication, in reducing the risk of high altitude sickness Research Hypothesis (if relevant): N/A 1. Material & Methods: 1. Whether study involves Human/animals or both : Human 2. Population/ participants: Patients presenting in Emergency Ward of District Hospital, Mustang with AMS (Acute Mountain Sickness), HAPE (High altitude Pulmonary Oedema) or HACE (High altitude Cerebral Oedema) as CASES Healthy volunteers who didn't develop any symptoms of AMS/HAPE/HACE after their trip to high altitude as CONTROLS 3. Type of study design: : Case Control Study 4. Human study : Inclusion Criteria: Cases: Individuals age 18 years or older who have been diagnosed with AMS based on a LLS score of ≥3 or HAPE or HACE. Controls: Individuals age 18 years or older who did not develop AMS during their trip to high altitude as the cases, and who are matched to cases on age and sex. Exclusion Criteria: - Those who deny consent for participation. - Age<18 years - Pregnant Women 5. Expected sample size : Sample size calculation: Mentioned in methodology 6. Control groups : N/A 7. Probable duration of study: 180 days 8. Setting: Emergency Ward 9. Parameter/Variables to be applied/measured Independent Variables i. Socio-demographic characteristics such as age, sex, address, nationality. Dependent Variables: i. Symptoms of Presentation ii. Ascent Rate iii. Co-morbidities iv. Past History including previous history of altitude sickness v. Personal History such as smoking, alcohol intake, recreational drugs vi. Awareness on High Altitude Sickness vii. Intake of Prophylactic medicine (Acetazolamide) viii. Past history of Covid-19 , TB Outcome measures: Primary (main outcome): All dependent variables (i) Rational for statistical methods to be employed : Data will be entered in Microsoft Excel and converted it into SPSS for statistical analysis . Descriptive statistics will be used to summarize the characteristics of cases and controls. Univariate and multivariate logistic regression analyses will be performed to assess the association between risk factors and high altitude sickness. The results will be reported as odds ratios with corresponding 95% confidence intervals. A p-value of less than 0.05 will be considered statistically significant. (ii) Ethical clearance : Ethical clearance will be obtained from National Health Research Council of Nepal (iii) Permission to use copyright questionnaire/Pro forma: Not applicable (j) Maintain the confidentiality of subject Confidentiality of the participants will be maintained. Whether available resources are adequate: Yes 1. Other resources needed: No 2. For Intervention trial: Not applicable
Dyspnea and exercise intolerance are well known to travelers who have experienced time at high elevations, greater than 2500 meters (8200 feet). As individuals ascend to higher elevations, oxygen saturations significantly decrease as the partial pressure of oxygen decreases. Additionally, many individuals develop subclinical cases of high altitude pulmonary edema (HAPE), which may worsen hypoxemia and decrease exercise performance. While dyspnea and exercise intolerance are usually self-limiting and improve with rest, some individuals experience severe symptoms that prevent safe evacuation to lower elevation. Individuals experiencing high altitude dyspnea, subclinical HAPE, or clinical HAPE will see improvements in symptoms and SpO2 when receiving supplemental oxygen, however this requires heavy and unwieldy tanks that make it difficult to carry across irregular terrain. Additionally, given the often-remote conditions where supplemental oxygen is needed, it is often difficult to replenish supplies. Other devices, such as the portable hyperbaric chamber (often referred to as Gamow bag), can temporarily improve dyspnea and oxygen saturation at high and extreme altitudes without the use of oxygen tanks. This device also carries some of the same disadvantages as supplemental oxygen, however, as the bag is also heavy and patients are not ambulatory while using the device. Similar to supplemental oxygen and the portable hyperbaric chamber, there is some evidence that CPAP may improve SpO2 and dyspnea at high and extreme altitudes. CPAP has already demonstrated significant efficacy in reducing symptoms of acute mountain sickness (AMS) when used in the field. At the time these small studies were conducted, CPAP therapy carried similar disadvantages in weight and portability. In recent years, however, CPAP devices have become increasingly lightweight and portable, with recent models weighing less than 1 kilogram (2.2 pounds). These devices are often powered by batteries, which themselves are light and easy to carry, and can be charged in the field using either a generator or foldable solar panels. These newer features of CPAP devices overcome some of the previous disadvantages that have limited its potential uses. CPAP devices can easily be carried across difficult terrain directly to individuals suffering from altitude-related symptoms, to be used as a rescue device until definitive care is available. Its portability not only allows for easy delivery to a patient, but also may allow for a patient to experience enough symptom relief to walk themselves down to lower elevation, greatly improving speed and resource utilization involved in high altitude rescues. In previous studies, CPAP devices have been found to be effective and safe to use in high and extreme altitude locations. While a few pilot studies have assessed CPAP's utility in treating dyspnea and SpO2 at altitude, these studies were done at rest. While one study showed improved symptoms and SpO2 in normobaric and hypobaric hypoxia, the study was limited by its lack of real-world condition, and its authors suggested further study in field and extreme environmental conditions. Additional investigation is needed to determine whether or not CPAP is an effective tool in the field to improve SpO2, dyspnea, and exercise tolerance in individuals traveling at high elevations.
In this study, the objective is to compare neonatal cerebral oxygenation and electrical activity within 3 days after birth across different altitude areas using non-invasive methods, specifically near infrared spectroscopy (NIRS) and amplitude-integrated electroencephalography (aEEG), and establish reference value for each altitude level.
• 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
High altitude (>2400 m) is associated with decreased atmosphere pressure leading to hypoxia which in turn impairs exercise capacity and causes acute mountain sickness (AMS). It is noted that adding CO2 might be beneficial to improve hypoxia and exercise performance at high altitude. However, no device is currently available that can supply a constant low dose of CO2 during free movement at high altitude. We have recently invented a portable device which is small and light enough for supplement of low dose CO2 during field exercise at high altitude.
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).