Effects of Acute Hypobaric Hypoxia Exposure on Neurocognitive Performance of Pre-hospital Emergency Service Providers

Study Overview
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Brief Summary
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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.

Official Title
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Effects of Acute Hypobaric Hypoxia Exposure on Neurocognitive Performance of Pre-hospital Emergency Service Providers

Conditions
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Hypobaric Hypoxia, Cognitive Deterioration, Emergency Medicine, Resuscitation, Stress Physiology

Intervention / Treatment
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* Other: Altitude exposure in climate chamber


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Healthy volunteers Age 18-60 yr-old ASA class I Signed informed consent Exclusion criteria: Age <18 or >60 yr-old ASA class > I Informed consent not signed

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 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: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Interventional, non-pharmacological, randomized, controlled, single-blinded, cross-over
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 200-3000<br>Day 1: 200m (above sea level) asl Day 2: 3000m asl | Other: Altitude exposure in climate chamber<br>* Altitude exposure in a climate chamber will consist of hypobaric hypoxia similar to the conditions found at 3000m asl and 5000m asl.<br>|
| Experimental: 3000-200<br>Day 1: 3000m asl Day 2: 200m asl | Other: Altitude exposure in climate chamber<br>* Altitude exposure in a climate chamber will consist of hypobaric hypoxia similar to the conditions found at 3000m asl and 5000m asl.<br>|
| Experimental: 200-5000<br>Day 1: 200m asl Day 2: 5000m asl | Other: Altitude exposure in climate chamber<br>* Altitude exposure in a climate chamber will consist of hypobaric hypoxia similar to the conditions found at 3000m asl and 5000m asl.<br>|
| Experimental: 5000-200<br>Day 1: 5000m asl Day 2: 200m asl | Other: Altitude exposure in climate chamber<br>* Altitude exposure in a climate chamber will consist of hypobaric hypoxia similar to the conditions found at 3000m asl and 5000m asl.<br>|
| Experimental: 3000-5000<br>Day 1: 3000m asl Day 2: 5000m asl | Other: Altitude exposure in climate chamber<br>* Altitude exposure in a climate chamber will consist of hypobaric hypoxia similar to the conditions found at 3000m asl and 5000m asl.<br>|
| Active Comparator: 5000-3000<br>Day 1: 5000m asl Day 2: 3000m asl | Other: Altitude exposure in climate chamber<br>* Altitude exposure in a climate chamber will consist of hypobaric hypoxia similar to the conditions found at 3000m asl and 5000m asl.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Digit-Symbol Substitution Task - DSST | Changes in working memory at altitude using a computer-based test (DSST) | Change from basal measurement (before altitude exposure) to altitude measurement (after altitude exposure - 5 minutes) | 
| Balloon Analog Risk Test - BART | Changes in risk-taking behavior at altitude using a computer-based test (BART) | Change from basal measurement (before altitude exposure) to altitude measurement (after altitude exposure - 5 minutes) | 
| Psychomotor Vigilance Test - PVT | Changes in reaction time using a computer-based test (PVT) | Change from basal measurement (before altitude exposure) to altitude measurement (after altitude exposure - 5 minutes) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Digit-Symbol Substitution Task - DSST | Changes in working memory after exercise at altitude using a computer-based test (DSST) | Change from rest measurement (altitude exposure before chest compressions) to post-exercise measurement (after 5 minutes of chest compressions at altitude) | 
| Balloon Analog Risk Test - BART | Changes in risk-taking behavior after exercise at altitude using a computer-based test (BART) | Change from rest measurement (altitude exposure before chest compressions) to post-exercise measurement (after 5 minutes of chest compressions at altitude) | 
| Psychomotor Vigilance Test - PVT | Changes in reaction time after exercise at altitude using a computer-based test battery (PVT) | Change from rest measurement (altitude exposure before chest compressions) to post-exercise measurement (after 5 minutes of chest compressions at altitude) | 
| Proportion of correct chest compressions regarding depth, pressure point and pressure release | Evaluation of the quality of chest compressions with a manikin and its electronic feedback device at different altitudes (200 meters vs. 3000 meters vs. 5000 meters) | Changes in 5 minute chest compressions | 
| Reactive oxygen species - ROS | Changes in ROS in saliva samples (μmol/min) | Change from basal measurement (before altitude exposure) to post-altitude measurement (after altitude exposure - 1 hour) | 
| Total antioxidant capacity - TAC | Changes in TAC in saliva samples (mM) | Change from basal measurement (before altitude exposure) to post-altitude measurement (after altitude exposure - 1 hour) |