Gas narcosis in hyperbaric environments

Not Applicable

Completed

• Conditions: gas narcosis; Anaesthesiology - Other anaesthesiology; Neurological - Studies of the normal brain and nervous system

• Registration Number: ACTRN12618000369224
• Lead Sponsor: Professor Simon Mitchell

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2018-03-12
• Study Completion: 2022-10-25
• Last Update Posted: 13 March 2023

Recruitment & Eligibility

• Status: Completed
• Sex: All
• Target Recruitment: 34

Inclusion Criteria

• Age between 18 and 55 years old
• Written informed consent
• Normal static binocular acuity, corrected or uncorrected
• Normal hearing
• Basic fluency of the English language
• Possession of a valid divers certificate
• Medical fitness for diving according to recreational diver standards.

Exclusion Criteria

A potential subject who meets any of the following criteria will be excluded from participation in this study:
• Current recreational drug use
• Use of psychoactive medication, including anti-histamines
• Mental illness
• Excessive alcohol use (>21 standard alcoholic drinks per week)
• Intake of caffeine-containing beverages over 5 glasses per day
• Smoker

After inclusion a participant will be withdrawn from the study if:
• There is a deviation of the research protocol by the participant
• There is an intake of non-permitted medication
• There is an intake of alcohol 24 hours before the test
• There is an intake of caffeine-containing beverages during the test days
• Less than 6 hours of sleep during the night prior to the test day
• A dive made within 24 hours prior to the an experiment involving hyperbaric exposure
• There are signs or symptoms of decompression illness
• They request to be withdrawn

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
relative change in narcosis depth measured with a to be developed quantitative EEG measurement<br><br>I will use the EEG recordings with the known narcotic effect of nitrous oxide to create a narcosis evaluation tool. This tool will provide an outcome measure on a numerical scale. Out of the many possible qEEG indicators, the subset with the highest correlation with psychometric performance, robustness to noise and interindividual variation will be chosen.[baseline (before exposure) and for the duration of 10 minutes during exposure to the breathing gas mixture.]