Brain Networks and Consciousness

NCT ID: NCT04502550

Last Updated: 2025-02-19

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

COMPLETED

Total Enrollment

63 participants

Study Classification

OBSERVATIONAL

Study Start Date

2020-10-15

Study Completion Date

2024-11-14

Brief Summary

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General anesthesia (GA) is a medically induced state of unresponsiveness and unconsciousness, which millions of people experience every year. Despite its ubiquity, a clear and consistent picture of the brain circuits mediating consciousness and responsiveness has not emerged. Studies to date are limited by lack of direct recordings in human brain during medically induced anesthesia. Our overall hypothesis is that the current model of consciousness, originally proposed to model disorders and recovery of consciousness after brain injury, can be generalized to understand mechanisms of consciousness more broadly. This will be studied through three specific aims. The first is to evaluate the difference in anesthesia sensitivity in patients with and without underlying basal ganglia pathology. Second is to correlate changes in brain circuitry with induction and emergence from anesthesia. The third aim is to evaluate the effects of targeted deep brain stimulation on anesthesia induced loss and recovery of consciousness. This study focuses on experimentally studying these related brain circuits by taking advantage of pathological differences in movement disorder patient populations undergoing deep brain stimulation (DBS) surgery. DBS is a neurosurgical procedure that is used as treatment for movement disorders, such as Parkinson's disease and essential tremor, and provides a mechanism to acquire brain activity recordings in subcortical structures. This study will provide important insight by using human data to shed light on the generalizability of the current model of consciousness. The subject's surgery for DBS will be prolonged by up to 40 minutes in order to record the participant's brain activity and their responses to verbal and auditory stimuli.

Detailed Description

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Conditions

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Loss of Consciousness Parkinson Disease Essential Tremor Anesthesia

Study Design

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Observational Model Type

CASE_CONTROL

Study Time Perspective

PROSPECTIVE

Study Groups

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Parkinson's Disease patients with DBS, no stimulation

This cohort will serve as as the observed group, displaying basal ganglia pathology.

A syringe pump controlled by Stanpump implementing the Eleveld Pharmacokinetics-Pharmacodynamics (PK-PD) model for propofol will be used as a targeted controlled infusion (TCI) system to achieve plasma target propofol concentrations. Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Experiments will be completed with DBS off.

Propofol

Intervention Type DRUG

Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Essential Tremor patients with DBS

This cohort will serve as a control group (no basal ganglia pathology). A syringe pump controlled by Stanpump implementing the Eleveld Pharmacokinetics-Pharmacodynamics (PK-PD) model for propofol will be used as a TCI system to achieve plasma target propofol concentrations. Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Experiments will be completed with DBS off.

Propofol

Intervention Type DRUG

Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Parkinson's Disease patients with DBS, Gpi stimulation

This cohort will serve as as the observed group, displaying basal ganglia pathology.

A syringe pump controlled by Stanpump implementing the Eleveld Pharmacokinetics-Pharmacodynamics (PK-PD) model for propofol will be used as a targeted controlled infusion (TCI) system to achieve plasma target propofol concentrations. Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Participants will be stimulated at the Gpi via DBS leads during propofol induced loss of consciousness.

Propofol

Intervention Type DRUG

Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Parkinson's Disease patients with DBS, Gpe stimulation

This cohort will serve as as the observed group, displaying basal ganglia pathology.

A syringe pump controlled by Stanpump implementing the Eleveld Pharmacokinetics-Pharmacodynamics (PK-PD) model for propofol will be used as a targeted controlled infusion (TCI) system to achieve plasma target propofol concentrations. Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Participants will be stimulated at the Gpe via DBS leads during propofol induced loss of consciousness.

Propofol

Intervention Type DRUG

Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Parkinson's Disease patients undergoing DBS surgery, Gpe stimulation

A syringe pump controlled by Stanpump implementing the Eleveld Pharmacokinetics-Pharmacodynamics (PK-PD) model for propofol will be used as a targeted controlled infusion (TCI) system to achieve plasma target propofol concentrations. Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Participants will be stimulated at the Gpe via DBS leads, and cortical activity will be recorded via ECoG during propofol induced loss of consciousness.

Propofol

Intervention Type DRUG

Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Parkinson's Disease patients undergoing DBS surgery, Gpi stimulation

A syringe pump controlled by Stanpump implementing the Eleveld Pharmacokinetics-Pharmacodynamics (PK-PD) model for propofol will be used as a targeted controlled infusion (TCI) system to achieve plasma target propofol concentrations. Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Participants will be stimulated at the Gpi via DBS leads, and cortical activity will be recorded via ECoG during propofol induced loss of consciousness.

Propofol

Intervention Type DRUG

Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Parkinson's Disease patients undergoing DBS surgery, no stimulation

A syringe pump controlled by Stanpump implementing the Eleveld Pharmacokinetics-Pharmacodynamics (PK-PD) model for propofol will be used as a targeted controlled infusion (TCI) system to achieve plasma target propofol concentrations. Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Participants will not receive any stimulation via DBS leads, and cortical activity will be recorded via ECoG during propofol induced loss of consciousness.

Propofol

Intervention Type DRUG

Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Interventions

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Propofol

Target effect-site concentration of propofol will be started at 1.4 μg/mL and will be increased by 0.3 μg/mL with reassessment until endpoints are achieved.

Intervention Type DRUG

Eligibility Criteria

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Inclusion Criteria

* Willingness and ability to cooperate during conscious operative procedure for up to 40 minutes
* Clinical diagnosis of Parkinson's disease or essential tremor
* Preoperative MRI without evidence of cortical or subdural adhesions or vascular abnormalities

Exclusion Criteria

* Patients with recent use (within one week) of anticoagulant or antiplatelet agent use
* Neurocognitive testing indicating amnestic cognitive deficits
* History of intolerance of propofol or medical indications to use an anesthetic other than propofol
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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University of California, Los Angeles

OTHER

Sponsor Role collaborator

University of Texas Southwestern Medical Center

OTHER

Sponsor Role lead

Responsible Party

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Nader Pouratian

Professor of Medicine

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

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Nader Pouratian, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

University of Texas Southwestern Medical Center

Locations

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Nader Pouratian

Dallas, Texas, United States

Site Status

Countries

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United States

Other Identifiers

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STU-2021-0396

Identifier Type: -

Identifier Source: org_study_id

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