None listed
Conditions
Brief summary
Despite many decades of effective and safe use the mechanisms by which anaesthetics induce unconsciousness remain unresolved. While our knowledge of the molecular and cellular targets of anaesthetic action has increased substantially in the last couple of decades our knowledge regarding their effects on measured brain activity has progressed at a slower rate. The aim of this study is, for the first time, to use a high resolution method of brain imaging to better quantify the effects anaesthetic agents have on brain activity. Specifically we will quantify the effects of two volatile anaesthetic agents, nitrous oxide and xenon, on brain activity recorded using a high resolution brain imaging technique known as magnetoencephalography. These agents are chosen because of their reported differing effects on brain activity, their reported similar molecular targets of action and the fact that they are safe to administer in a research imaging environment.
Interventions
Participants will be administered nitrous oxide and xenon in separate experimental sessions. Each experimental session will be separated by a period of 1 week to allow for washout of respective gas effects. Participants will be randomized to initially receive step-wise inhaled concentrations of either nitrous oxide or xenon. Nitrous oxide will be administered as a sequence of 3 inspired concentrations of 16%, 32% and 47% each lasting for 15 minutes and each separated by a period of 5 minutes of
Participants will be administered nitrous oxide and xenon in separate experimental sessions. Each experimental session will be separated by a period of 1 week to allow for washout of respective gas effects. Participants will be randomized to initially receive step-wise inhaled concentrations of either nitrous oxide or xenon. Nitrous oxide will be administered as a sequence of 3 inspired concentrations of 16%, 32% and 47% each lasting for 15 minutes and each separated by a period of 5 minutes of 100% oxygen. Xenon will be administered as a sequence of 3 inspired concentrations of 8%, 16% and 24% each lasting for 15 minutes and each separated by a period of 5 minutes of 100% oxygen followed by Xenon administered at an inspired concentration of 42% until loss of response to a vocal command.
Sponsors
Swinburne University of Technology
Study design
Allocation
Randomised controlled trial
Primary purpose
Diagnosis
Eligibility
Sex/Gender
Male
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
Healthy males aged 18 - 40 years Non-smoker Right handed Able to read, write and speak English
Exclusion criteria
A history of epilepsy or other neurological condition A history of depression, anxiety or other psychiatric illness Asthma or other respiratory illness Obstructive sleep apnoea or severe snoring A history of alcohol or drug abuse Taken any pharmaceutical product/medicine in the last 30 days prior to first gas administration session
Outcome results
None listed