View clinical trials related to Altitude Sickness.
Filter by:A field-based trial was conducted to determine if oral prochlorperazine demonstrates efficacy in the prophylactic treatment of AMS, and/or decreases the incidence of the symptoms of acute mountain sickness including headache, GI symptoms, fatigue and dizziness based on data collected in the Lake Louise AMS score.
- Cognitive assessment of the influence of a 4-week proprietary training program under normobaric hypoxia conditions on the levels of inflammatory markers, disturbances in prooxidant-antioxidant balance, degree of intestinal damage, and mitochondrial energy production rate in young sedentary males. - Applied objective: Development of practical training guidelines utilizing training in normobaric hypoxia conditions to enhance mechanisms related to oxygen transport, adaptive changes within the immune system, body's antioxidant capacity, gut permeability, substrate utilization efficiency, and mitochondrial function for coaches and athletes.
One approach to significantly reducing resistance training intensity while maintaining effectiveness in muscle mass and strength development involves conducting training sessions under hypoxic conditions. This is likely due to heightened physiological responses. While sports science research indicates a substantial impact of hypoxic conditions on immediate increases in metabolic stress and augmented hormonal responses, recent findings suggest that the role of their influence on skeletal muscle adaptations post-resistance training under hypoxic conditions remains unknown. Additionally, there is a lack of reports on whether the type of hypoxia applied via blood flow restriction or chamber differentiates the increase in secretion of these catecholamines in both immediate and long-term aspects.
Apparent hypoxia-induced insulin insensitivity along with alterations in glucose kinetics suggests reduction in glucose uptake by the peripheral tissue is a primary factor contributing to reductions in exogenous glucose oxidation at HA. As such, the primary objective of this study is to determine the ability of an insulin sensitizer (Pioglitazone, PIO) to enhance exogenous glucose oxidation and metabolic clearance rate during metabolically-matched, steady-state exercise during acute HA exposure compared to placebo (PLA) in native lowlanders. Secondary objective of this study will be to assess the impact of PIO on markers of inflammation and iron status compared to PLA. This randomized crossover placebo control double blinded study will examine substrate oxidation and glucose kinetic responses to ingesting supplemental carbohydrate (glucose) during metabolically-matched, steady-state exercise with acute (~5 h) exposure to HA (460 mmHg, or 4300m, barometric pressure similar to Pike's Peak) after receiving PIO (HA+PIO), or after receiving a matched placebo (HA+PLA). Eight healthy, recreationally active males between the ages of 18-39 yrs will be required to complete this study. Following a 4 day glycogen normalization period receiving PIO or PLA daily, volunteers will complete two 80-min trials, performing metabolically-matched, steady-state aerobic (same absolute workload corresponding to ~55 ± 5% of V̇O2peak at HA) exercise on a treadmill, and consuming 145 g of glucose (1.8 g/min); one trial with HA+PIO and the other with HA+PLA. A dual glucose tracer (13C-glucose oral ingestion and [6,6-2H2]-glucose primed, continuous infusion) technique and indirect calorimetry will be used to selectively analyze endogenous and exogenous glucose oxidation, as well as glucose rate of appearance (Ra), disappearance (Rd) and metabolic clearance rate (MCR). Serial blood samples will be collected during each trial to assess endocrine and circulating substrate responses to exercise, carbohydrate, and hypoxia with or without PIO. All trials will occur at the same time of day in the USARIEM hypobaric/hypoxic chamber and be separated by a minimum 10-d washout period. The primary risks associated with this study include those associated with acute hypobaric hypoxia, exercise, and blood sampling.
The main objective of the study is to evaluate the physiological-biochemical effects of physical training under artificially altered climatic conditions (using a hypoxic thermoclimatic chamber) in particular to determine the effect of such training on exercise capacity and physiological response, including the effect of training in high-performance athletes. The study will evaluate the effects of physical training and the simultaneous application of hypoxia and heat/cold on aerobic and anaerobic capacity and the physiological response of the human body. The aim of the study is to find the most favourable environmental conditions for physical training in order to maximise physical performance.
Over the last 20 years, extracorporeal membrane oxygenation (ECMO) has been used to support adult patients with respiratory or cardiac failure who are unlikely to survive conventional treatment methods. ECMO circuit, pump, and oxygenator technology improvements permit safer perfusion for extended periods. The prolonged use of an ECMO circuit increases the risk of membrane lung (ML) dysfunction. The ML is responsible for taking in oxygen and removing carbon dioxide. The non-biologic surface of the ML triggers inflammatory and coagulation pathways, resulting in the formation of blood clots, breakdown of fibrin, and activation of white blood cells, which ultimately leads to ML dysfunction. Coagulation and fibrinolysis activation can cause systemic coagulopathy or hemolysis, and the deposition of blood clots can block blood flow. Moreover, the accumulation of moisture in the gas phase and the buildup of protein and cellular debris in the blood phase may contribute to shunt and dead-space physiology, respectively, impairing the exchange of gases. These three categories-hematologic abnormalities, mechanical obstruction, and inadequate gas exchange-account for most ML exchanges. Worsening oxygenation during ECMO should prompt quantification of oxygen transfer. ML exchange is indicated when the ML can no longer meet the patient's oxygen demand. The partial pressure of Post-ML arterial oxygen less than 200 mmHg is the most important consideration in making this decision. In some high-altitude regions of China, ECMO treatment is also routinely conducted. The experiences above are derived from low-altitude areas, and whether they apply in high-altitude regions is still being determined. This study aimed to explore the significantly lower post-membrane oxygen partial pressure in high-altitude regions compared to low-altitude areas.
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.