Neural Mechanisms of Sevoflurane Induced Anesthesia: an EEG fMRI Study in Healthy Volunteers

Early Phase 1

Completed

• Conditions: Anesthesia; Drug Effects
• Interventions: Drug: Sevoflurane

• Registration Number: NCT02149927
• Lead Sponsor: Technical University of Munich

Brief Summary

In imaging functional connectivity (FC) analyses of the resting brain, alterations of FC during unconsciousness have been reported. These results are in accordance to recent electroencephalographic studies observing impaired top-down processing during anesthesia. In this study, simultaneous records of functional magnetic resonance imaging (fMRI) and electroencephalogram (EEG) were performed to investigate the causality of neural mechanisms during sevoflurane anesthesia by correlating FC in fMRI and directional connectivity (DC) in electroencephalogram.

Detailed Description

Not available

Study Timeline

• Study Start: 2013-06
• Primary Completion: 2013-12
• Study Completion: 2014-01
• Study First Submitted: 2014-04-22
• Status Verified: 2014-05
• Study First Submitted QC: 2014-05-23
• Last Update Submitted: 2014-05-23
• Study First Posted: 2014-05-29
• Last Update Posted: 2014-05-29

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 20

Inclusion Criteria

• ASA I
• male
• age > 18y

Exclusion Criteria

• drug abuse
• history of psychiatric or neurologic diseases
• amblyacousia, deafness
• contradictions to the study drug (sevoflurane)
• implants
• piercings, tatoos

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Sevoflurane	Sevoflurane	Single arm: dose escalation of study medication

Primary Outcome Measures

Name	Time	Method
Changes of information processing (entropy) in EEG and functional connectivity (BOLD ICA and small group network architecture) in fMRI during sevoflurane anesthesia at states awake, 2vol%, 3vol% and EEG endpoint burst suppression	10 minutes for each condition	Changes of fMRI functional connectivity and of EEG information processing during different levels of sevoflurane anesthesia from wakefulness to deep anesthesia: At each anesthetic level at equilibrated states awake, 2vol%, 3vol% and EEG endpoint burst suppression, EEG and fMRI are recorded simultaneously for about 10 minutes. For each level EEG and fMRI connectivity analysis are performed using the recording length of 10 minutes. This results in one outcome parameter for EEG and fMRI connectivity. Furthermore, both modalities are combined resulting in one combined parameter for each level.; For EEG analysis permutation entropy as a measure of information content in EEG, and symbolic transfer entropy as a measure of directed interaction in EEG are used. fMRI functional connectivity analysis is based on BOLD ICA and on network analysis of the BOLD time series.

Secondary Outcome Measures

Name	Time	Method
Assessment of the brain network structure during recovery in EEG and fMRI	10 minutes for each condition	Identical technical setup than main outcome

Trial Locations

Locations (1)

Klinikum rechts der Isar; 🇩🇪 Munich, Bayern, Germany