The Effects of Hypobaria vs Hypoxia on Cerebral Functions.

Study Overview
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Brief Summary
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The investigators will investigate the effect of hypobaria and hypoxia on physiological responses such as: oxygen saturation, heart rate, cerebral blood flow, cerebral oxygenation, brain's activity and concentration performance.

Detailed Description
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The main goal of this project is to investigate how hypoxia affects cognitive functions. The KLT-R test asses the concentration level of a person. Subjects will do this test at different simulated altitude level in the hypobaric chamber at the FAI in Dübendorf. Investigators' first hypothesis is that concentration level will be altered by hypoxia. The higher altitude the subjects are, the more the concentration would be altered. KLT-R performance would be impaired by hypoxia compare to sea level performance. The primary endpoint of this project is to investigate how KLT-R performance is affected by the different hypoxic conditions. KLT-R test will be passed nine times in total during the test visit. There will be a pre-test; a test at each of the conditions (3000m HH, 5500m HH, 5500m NH and 5500m HN); between each condition at sea level (to have a new baseline before each condition) and a post-test at the end of the protocol. To avoid influence of fatigue, all conditions will be randomized. The second endpoint of this study is how the brain electrical activity is modulated by hypoxia. Micro-states also will be measure during hypobaric hypoxia conditions (3000m HH and 5500m HH).

Official Title
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The Effects of Hypobaria vs Hypoxia on Cerebral Vasoreactivity, Brain's Electrical Activity and Concentration Performance on Pilots.

Conditions
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Cerebral Hypoxia

Intervention / Treatment
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* Other: Hypoxia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: No history of flight sickness No relevant medical diseases Age 18 - 40 years Written consent acceptance Exclusion Criteria: Known pathologies Relevant medical disorders Drug addiction Anemia or poor health People who have already had problems with elevation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Interventional Model Description: Single-Blind study.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Left<br>No product administration will be done in this study. | Other: Hypoxia<br>* No drug or product will be used in this study. No medication will be give to the participants. No arm will be used for product administration.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concentration performance | Performance of concentration at different altitude levels. | 4 minutes per test | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| EEG micro-states | 5 minutes recording in each conditions, eyes closed, at rest. | 5 minutes per record | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypoxia, Brain, Cerebral vaso-reactivity, EEG, Concentration performance, Cerebral oxygenation, Cerebral blood-flow, Heart rate variability