View clinical trials related to Hypobaric Hypoxia.
Filter by:Rescue services in mountainous regions are frequently called to missions at altitudes >3000 m. Under the difficult conditions of acute exposure to altitude, the crews then have to undertake demanding medical and rescue measures. Previous studies in non-medical personnel, such as astronauts, aircraft pilots, and military helicopter pilots have found that the lack of oxygen associated with acute exposure to altitude may impair cognitive functions. No data exists on the effect this may have on the performance of medical staff in terms of patient examination, communication, decision-making, planning, and overall patient care. This study aims to close this knowledge gap. The investigators of this study aim to make rescue missions to high altitude safer for both the patients and the rescuers. To assess the effect of high altitude on patient care, the investigators recruit highly trained medical specialists who will perform patient care in simulated scenarios both at high altitude and at low altitude. These scenarios will be recorded and the performance of the medical specialists judged by independent reviewers. The medical specialists will also perform in simulated scenarios at high altitude two more times: once with supplementary oxygen, and once after spending a night at high altitude. the investigators do this to evaluate whether supplementary oxygen improves their performance, and whether symptoms of acute mountain sickness (which usually develop after spending the first night at high altitude) decreases their performance further.
The aim of this randomized, double-blind study is to determine whether erythropoietin (Procrit) and acetazolamide: 1) mitigates altitude-induced decrements in performance at moderate altitude (3,000 m) and 2) mitigates altitude-induced decrements in performance and reduce acute mountain sickness during prolonged exposure to high altitude (4,300 m; 15 days). Volunteers will complete 5 study phases: Phase 1) sea level baseline testing and a moderate altitude exposure; Phase 2) 4 week study intervention - randomly assigned to receive erythropoietin or placebo); Phase 3) 3 1/2 days of acetazolamide and a moderate altitude exposure; Phase 4) high altitude acclimatization - 15 days at Pikes Peak; and Phase 5) two week deacclimatization. Test battery include VO2peak, 3.2 km treadmill time trial, measures of gas exchange and ventilation during rest and exercise, and blood collection.
The aim of the current study is to evaluate under blinded conditions, both in a simulated environment and during helicopter flight, the effect of a rapid (within 20 minutes) exposure to altitude (4000 m asl) on physiological parameters and selected cognitive domains, in providers operating in helicopter emergency medical service (HEMS) exposed to hypobaric hypoxia or to hypobaric normoxia (H0: cognitive effects under hypobaric hypoxia = cognitive effects under hypobaric normoxia). Simulated environment will allow to control different factors. The parallelism between a study branch conducted in a simulated environment and another one conducted under a real-life condition will allow to evaluate the additive effects on additional stressor factors (processive and systemic ones). - Simulation branch: each participant will take part in three research sessions: a familiarization session and two experimental sessions in simulation facility called terraXcube (test 1 and 2). On test 1 and test 2 each group will be exposed twice to the simulated altitude of 4000 m asl (under hypobaric hypoxia or hypobaric normoxia conditions) according to the randomization protocol. Participants will perform the neurocognitive tests three times on each of the two tests: before the ascent (TC0), after 5 min from the end of the ascent (TC1) and after around 30 min (TC2), to investigate European Union Aviation Safe Agency (EASA) proposed recommendations. After completing each neurocognitive test session, participants will be asked to rate their performance using a visual analogue scales (VAS). All participants will wear the vital parameters monitoring system during the entire duration of the tests inside the chamber, as well as the cerebral oxygen saturation (ScO2) sensor. Samples will be collected by saliva, urine and/or capillary blood. The same schedule is repeated in each test session. - In-field branch: each participant will take part in three research sessions: a familiarization session and two experimental sessions during helicopter flights (test 1 and 2). On test 1 and test 2 each group will be exposed twice to the altitude of 4000 m (under hypobaric hypoxia or hypobaric normoxia conditions) according to the randomization protocol. Participants will perform the neurocognitive test two times on each test: before the ascent (TC0), after around 5 min from the end of the ascent (TC1). After completing each neurocognitive tests, participants will be asked to rate their performance using a visual analogue scales (VAS). All participants will wear the vital parameters monitoring system during the entire duration of the tests. Samples will be collected. The same schedule is planned in each test session.
The study aims to evaluate the effects of acute hypobaric hypoxia on cognitive performance (H0: cognitive performance at 200 meters above sea level (asl) = cognitive performance at 3000 meters above sea level = cognitive performance at 5000 meters above sea level). Before participating in the study, each participant will respond to a questionnaire related to high altitude exposure (prior 3 months), as well as inclusion/exclusion criteria evaluation. On day 0, after the interview and signed informed consent, the participant will undergo a medical examination that will include a general objective examination. Participants will participate in a training on the emergency and safety procedures of the hypobaric hypoxia facility, as well as a refresh on cardiopulmonary resuscitation procedure. During the following two days (day 1 and 2) the study protocol will be executed (one test per day). The study protocol envisages: - a basal cognitive test battery - blind ascent in the hypobaric chamber to simulated altitude - cognitive test battery - 5 minutes of recorded chest compressions on dummies - cognitive test battery - blind descent in the hypobaric chamber. During the stay in the hypobaric hypoxic facility, each participant will be monitored in real time with the Equivital© medical monitoring device. Before and after the stay in the hypobaric hypoxic facility, a saliva sample will be collected, and psychological tests administered.
The trial investigates changes in metabolism during high altitude expedition up to 6865m. A mass-spectrometry based platform is used to detect different oxidative stress related metabolites. Symptoms of acute mountain sickness are evaluated and correlated with laboratory parameters.