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

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.

Study Overview

• Status: Completed
• Conditions: Emergency Medicine; Cognitive Deterioration; Stress Physiology; Resuscitation; Hypobaric Hypoxia
• Intervention / Treatment: Other: Altitude exposure in climate chamber

• Study Type: Interventional
• Enrollment (Actual): 48
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Italy
  • BZ
    • Bolzano, BZ, Italy, 39100
      • Eurac research, Institute of mountain emergency medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

6

Arms and Interventions

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

What is the study measuring?

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)

Collaborators and Investigators

• Sponsor: Institute of Mountain Emergency Medicine
• Collaborators: Medical University Innsbruck; Università degli Studi di Trento; University of Graz; Istituto di Fisiologia Clinica CNR; Azienda Sanitaria dell'Alto Adige
• Investigators: Principal Investigator: Giacomo Strapazzon, MD PhD, Eurac research, Institute of mountain emergency medicine

Publications and helpful links

General Publications

• Taylor L, Watkins SL, Marshall H, Dascombe BJ, Foster J. The Impact of Different Environmental Conditions on Cognitive Function: A Focused Review. Front Physiol. 2016 Jan 6;6:372. doi: 10.3389/fphys.2015.00372. eCollection 2015.
• Pietsch U, Strapazzon G, Ambuhl D, Lischke V, Rauch S, Knapp J. Challenges of helicopter mountain rescue missions by human external cargo: need for physicians onsite and comprehensive training. Scand J Trauma Resusc Emerg Med. 2019 Feb 13;27(1):17. doi: 10.1186/s13049-019-0598-2.
• Li XY, Wu XY, Fu C, Shen XF, Yang CB, Wu YH. Effects of acute exposure to mild or moderate hypoxia on human psychomotor performance and visual-reaction time. Space Med Med Eng (Beijing). 2000 Aug;13(4):235-9.
• Bouak F, Vartanian O, Hofer K, Cheung B. Acute Mild Hypoxic Hypoxia Effects on Cognitive and Simulated Aircraft Pilot Performance. Aerosp Med Hum Perform. 2018 Jun 1;89(6):526-535. doi: 10.3357/AMHP.5022.2018.
• Basner M, Savitt A, Moore TM, Port AM, McGuire S, Ecker AJ, Nasrini J, Mollicone DJ, Mott CM, McCann T, Dinges DF, Gur RC. Development and Validation of the Cognition Test Battery for Spaceflight. Aerosp Med Hum Perform. 2015 Nov;86(11):942-52. doi: 10.3357/AMHP.4343.2015.
• Wang JC, Tsai SH, Chen YL, Hsu CW, Lai KC, Liao WI, Li LY, Kao WF, Fan JS, Chen YH. The physiological effects and quality of chest compressions during CPR at sea level and high altitude. Am J Emerg Med. 2014 Oct;32(10):1183-8. doi: 10.1016/j.ajem.2014.07.007. Epub 2014 Jul 30.
• Vogele A, van Veelen MJ, Dal Cappello T, Falla M, Nicoletto G, Dejaco A, Palma M, Hufner K, Brugger H, Strapazzon G. Effect of Acute Exposure to Altitude on the Quality of Chest Compression-Only Cardiopulmonary Resuscitation in Helicopter Emergency Medical Services Personnel: A Randomized, Controlled, Single-Blind Crossover Trial. J Am Heart Assoc. 2021 Dec 7;10(23):e021090. doi: 10.1161/JAHA.121.021090. Epub 2021 Dec 2.

Study record dates

Study Major Dates

• Study Start (Actual): October 25, 2019
• Primary Completion (Actual): November 11, 2019
• Study Completion (Actual): November 11, 2019

Study Registration Dates

• First Submitted: October 18, 2019
• First Submitted That Met QC Criteria: October 22, 2019
• First Posted (Actual): October 24, 2019

Study Record Updates

• Last Update Posted (Actual): March 24, 2020
• Last Update Submitted That Met QC Criteria: March 23, 2020
• Last Verified: March 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Signs and Symptoms, Respiratory; Emergencies; Hypoxia
• Other Study ID Numbers: 3489044136

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: All of the individual participant data collected during the trial, after deidentification
• IPD Sharing Time Frame: Data will be available within 6 months from study completion
• IPD Sharing Access Criteria: Access will be granted to primary collaborators who will be required to sign a Data Access agreement
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No