Brain Activity Under Sedation
Conditions
Brief summary
The purpose of this study is to investigate how the commonly used anesthetic drug propofol works in the brain to produce loss of consciousness. While under general anesthesia your brain waves will be measured using electroencephalogram (EEG). On a separate day, the patient's brain will be imaged using magnetic resonance imaging (MRI).
Interventions
DRUGPropofol
Propofol will be infused using a computer controlled delivery system running the program STANPUMP. Loss of consciousness will be defined as loss of response to auditory stimulus (button press).
Sponsors
National Institutes of Health (NIH)
Massachusetts General Hospital
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 36 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy, non-smoking male and female volunteers, ages 18-36 with normal body weight. * American Society of Anesthesiologists (ASA) physical status I
Exclusion criteria
* History of head trauma * Surgical aneurysm clips * Cardiac pacemaker * Prosthetic heart valve * Neurostimulator * Implanted pumps * Cochlear implants * Metal rods, plates * Screws * Intrauterine device * Hearing aid * Dentures (which might create NMR artifacts) * Metal injury to eyes
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| EEG Power in Alpha, Slow, and Delta Bands | 11 hours | We used EEG measurements to study the dynamics of loss of consciousness, auditory processing, sensation, and memory under general anesthesia induced with propofol. The EEG data in each of the three specific aims will be analyzed using spectral methods, source localization, and event-related potentials. Through spectral analysis, EEG power (in decibels) in alpha, slow, and delta bands are measured. |
Countries
United States
Participant flow
Pre-assignment details
Subjects with abnormal cardiological abnormality, failure of the hearing test, abnormal ECG reading, and other medical conditions were excluded. Ten subjects also voluntarily withdrawn consent due to scheduling conflicts.
Participants by arm
| Arm | Count |
|---|---|
| Active Study Arm Subjects recruited into this study will be required to undergo a base MRI scan of the brain. On a separate day propofol will be administered with concurrent EEG while subjects respond to stimuli.
Propofol: Propofol will be infused using a computer controlled delivery system running the program STANPUMP. Loss of consciousness will be defined as loss of response to auditory stimulus (button press). | 36 |
| Total | 36 |
Baseline characteristics
| Characteristic | Active Study Arm |
|---|---|
| Age, Continuous | 27 Years |
| Ethnicity (NIH/OMB) Hispanic or Latino | 1 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 35 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Sex: Female, Male Female | 18 Participants |
| Sex: Female, Male Male | 18 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 17 |
| other Total, other adverse events | 0 / 17 |
| serious Total, serious adverse events | 0 / 17 |
Outcome results
Primary
EEG Power in Alpha, Slow, and Delta Bands
We used EEG measurements to study the dynamics of loss of consciousness, auditory processing, sensation, and memory under general anesthesia induced with propofol. The EEG data in each of the three specific aims will be analyzed using spectral methods, source localization, and event-related potentials. Through spectral analysis, EEG power (in decibels) in alpha, slow, and delta bands are measured.
Time frame: 11 hours
| Arm | Measure | Group | Value (MEDIAN) |
|---|---|---|---|
| Active Study Arm | EEG Power in Alpha, Slow, and Delta Bands | Alpha Band Power | 10 Power of alpha band (decibels) |
| Active Study Arm | EEG Power in Alpha, Slow, and Delta Bands | Slow Band Power | 0.55 Power of alpha band (decibels) |
| Active Study Arm | EEG Power in Alpha, Slow, and Delta Bands | Delta Band Power | 2.5 Power of alpha band (decibels) |