A Phase 4 interventional study of Dexmedetomidine and Ketamine in Unconsciousness and Consciousness, sponsored by University of Wisconsin, Madison. Completed at 1 site in United States. Open to participants aged 18 Years to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2023-04-13.
Sponsored by University of Wisconsin, Madison · Phase 4, Interventional, and Basic science
This study will be a single-site, controlled, unblinded study at the University of Wisconsin to examine changes in the electroencephalogram during anesthesia and waking.
* 20 subjects will be recruited per drug, and subjects can be recruited to undergo multiple sedation protocols.
Screening:
Subjects will respond to the volunteer posts for the study by calling into a study specific phone number. They will complete a phone screening to determine basic eligibility for the study. At the beginning of the sedation session, participants will affirm that in the interval since their baseline visit, they have not acquired any of the cited exclusion criteria that would preclude participation. A review of these exclusion criteria will be completed by the Anesthesiologist. A standard pre-anesthetic assessment will be performed, including confirmation of NPO status, and documented using the standard Department of Anesthesiology pre-operative evaluation form.
The first sedative will be dexmedetomidine followed by ketamine, propofol and then midazolam (dependent on the availability of the drugs). Total enrollment in the study will be up to 80 subjects. Each sedation experiment will occur on separate days at least 28 days apart, if the subject chooses to participate in more than one session.
Inclusion Criteria:
Exclusion Criteria:
Difficult anesthesia: American Society of Anesthesiologists Physical Status greater than 1, per the discretion of the PI. Examples of ASA status include, but are not limited to:
Exclusion from Dexmedetomidine:
o Resting heart Rate\<60 bpm
Exclusion from Propofol:
o Reported egg allergy
Exclusion from Ketamine:
Additional exclusion criteria on the day of sedation:
Sedatives will be administered to participants while their brain activity is measured.
Drug: Dexmedetomidine · Drug: Ketamine · Drug: Propofol · Drug: Midazolam
20 participants will be administered Dexmedetomidine.
20 participants will be administered Ketamine.
20 participants will be administered Propofol.
20 participants will be administered Midazolam.
Occipital Delta Power Spectral Density by Conscious State and Study Group.
The difference in spontaneous EEG slow wave activity over posterior cortex between states of consciousness measured with high-density EEG equipment and reported in spectral power in the delta band (1-4 Hz) at electrode Oz. Disconnected conscious experience (dreaming), connected conscious experience (awareness of the external world), and unconsciousness (no report) was assessed when participants were roused from sedation or sleep.
Time frame: Intraoperative (During sedation-- up to 8 hours)
Number of Instances of Disconnected Conscious Experience (Dreaming) vs Connected Conscious Experience (Awareness of External World).
The number of instances of disconnected conscious experience (dreaming) versus connected conscious experience (awareness of the external world) during sedation is measured by subject self-report at the time of researcher initiated inquiry.
Time frame: Intraoperative (During sedation-- up to 8 hours)
Effect of Study Drug on Ability to Correctly Identify Shapes/Images
The ability to identify shapes/images in visual illusions measured by the NIH Toolbox. Will be reported by a computed score from NIH Toolbox for the Dimensional Change Card Sort Test (DCCS) and the Flanker Inhibitory Control \& Attention Test (Flanker). Both Flanker and DCCS use a 2-vector scoring method that takes accuracy and reaction time (if accuracy \>=80%) into account, resulting in a computed score that can range in value from 0-10. A higher score indicates better performance on the test.
Time frame: Intraoperative (During sedation-- up to 8 hours)
Effect of Study Drug on Ability to Correctly Identify Images
The ability to match sounds and images measured by the predictive coding task. Will be reported by a proportion correct as a decimal.
Time frame: Intraoperative (During sedation-- up to 8 hours)
Effect of Study Drug on Ability to Form Implicit Memory
Subjects will have a list of words read to them while under sedation and their ability to hear these words and form implicit memories of them will be assessed using a two-alternative forced choice task. Results will be reported as the average number of correct responses out of sixteen.
Time frame: Intraoperative (During sedation-- up to 8 hours)
Participants were recruited via an email that was sent to UW-Madison students and staff from August 2017 through March 2020. Interested participants would discuss study commitment and preliminary screening criteria with the study team over the phone. Eligible participants would meet with a faculty anesthesiologist at a screening visit to complete informed consent and for a history and physical examination and basic neuropsychological assessment to determine subsequent study visit eligibility.
| Milestone | All Study Participants |
|---|---|
| Started | 35 |
| Completed sedation and/or sleep visit | 27 |
| Completed sedation visit | 21 |
| Sleep | 15 |
| Dexmedetomidine | 20 |
| Ketamine | 15 |
| Propofol | 6 |
| Midazolam | 0 |
| Completed | 27 |
| Not completed | 8 |
The difference in spontaneous EEG slow wave activity over posterior cortex between states of consciousness measured with high-density EEG equipment and reported in spectral power in the delta band (1-4 Hz) at electrode Oz. Disconnected conscious experience (dreaming), connected conscious experience (awareness of the external world), and unconsciousness (no report) was assessed when participants were roused from sedation or sleep.
| log10(μV^2) | Dexmedetomidine | Ketamine | Propofol | Midazolam | Sleep |
|---|---|---|---|---|---|
| Connected Consciousness | 2.37 (2.31 to 2.46) | 1.62 (1.57 to 1.68) | 2.05 (1.94 to 2.15) | — | 2.1 (2.03 to 2.18) |
| Disconnected Consciousness | 2.57 (2.53 to 2.61) | 1.7 (1.57 to 1.84) | 2.34 (2.22 to 2.5) | — | 2.58 (2.52 to 2.65) |
| Unconsciousness | 2.68 (2.61 to 2.75) | 1.46 (1.16 to 1.83) | 2.51 (2.31 to 2.68) | — | 2.63 (2.47 to 2.83) |
The number of instances of disconnected conscious experience (dreaming) versus connected conscious experience (awareness of the external world) during sedation is measured by subject self-report at the time of researcher initiated inquiry.
| number of instances | Dexmedetomidine | Ketamine | Propofol | Midazolam | Sleep |
|---|---|---|---|---|---|
| Instances of Connected Consciousness | 70 | 180 | 56 | — | — |
| Instances of Disconnected Consciousness | 226 | 30 | 22 | — | — |
The ability to identify shapes/images in visual illusions measured by the NIH Toolbox. Will be reported by a computed score from NIH Toolbox for the Dimensional Change Card Sort Test (DCCS) and the Flanker Inhibitory Control \& Attention Test (Flanker). Both Flanker and DCCS use a 2-vector scoring method that takes accuracy and reaction time (if accuracy \>=80%) into account, resulting in a computed score that can range in value from 0-10. A higher score indicates better performance on the test.
| score on a scale | Dexmedetomidine | Ketamine | Propofol | Midazolam | Sleep |
|---|---|---|---|---|---|
| Baseline NIH Toolbox Card Sorting Score | 8.83 ± 1.21 | 9.29 ± 0.59 | 9.45 ± 0.95 | — | — |
| Sedation NIH Toolbox Card Sorting Score | 7.85 ± 1.49 | 8.2 ± 0.99 | 6.94 ± 4.16 | — | — |
| Baseline NIH Toolbox Flanker Score | 9.14 ± 0.67 | 8.99 ± 0.83 | 9.48 ± 0.12 | — | — |
| Sedation NIH Toolbox Flanker Score | 6.62 ± 0.88 | 8.47 ± 0.93 | 8.36 ± 0.96 | — | — |
The ability to match sounds and images measured by the predictive coding task. Will be reported by a proportion correct as a decimal.
| proportion correct | Dexmedetomidine | Ketamine | Propofol | Midazolam | Sleep |
|---|---|---|---|---|---|
| Baseline Predictive Coding Task Accuracy | 0.916 ± 0.07 | 0.899 ± 0.07 | 0.91 ± 0.09 | — | — |
| Sedation Predictive Coding Task Accuracy | 0.793 ± 0.09 | 0.763 ± 0.1 | 0.734 ± 0.15 | — | — |
Subjects will have a list of words read to them while under sedation and their ability to hear these words and form implicit memories of them will be assessed using a two-alternative forced choice task. Results will be reported as the average number of correct responses out of sixteen.
| correct responses | Dexmedetomidine | Ketamine | Propofol | Midazolam | Sleep |
|---|---|---|---|---|---|
| Effect of Study Drug on Ability to Form Implicit Memory | 8 ± 2.47 | 8.17 ± 1.70 | 9 ± 1.58 | — | — |
Collected over 24 hours after drug or sleep visit.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Dexmedetomidine | 0/20 (0%) | 0/20 (0%) | 5/20 (25%) |
| Ketamine | 0/15 (0%) | 0/15 (0%) | 6/15 (40%) |
| Propofol | 0/6 (0%) | 0/6 (0%) | 1/6 (16.7%) |
| Midazolam | — | — | — |
| Sleep | 0/15 (0%) | 0/15 (0%) | 0/15 (0%) |
| Event | Dexmedetomidine | Ketamine | Propofol | Midazolam | Sleep |
|---|---|---|---|---|---|
| VomitingGastrointestinal disorders | 1/20 | 4/15 | 0/6 | — | 0/15 |
| BruisingInjury, poisoning and procedural complications | 0/20 | 1/15 | 1/6 | — | 0/15 |
| NauseaGastrointestinal disorders | 1/20 | 2/15 | 0/6 | — | 0/15 |
| HypotensionCardiac disorders | 1/20 | 0/15 | 0/6 | — | 0/15 |
| BradycardiaCardiac disorders | 1/20 | 0/15 | 0/6 | — | 0/15 |
| Mild Chest PainCardiac disorders | 1/20 | 0/15 | 0/6 | — | 0/15 |
| Pain at injection siteInjury, poisoning and procedural complications | 1/20 | 0/15 | 0/6 | — | 0/15 |
| HeadacheNervous system disorders | 1/20 | 0/15 | 0/6 | — | 0/15 |
All participants who completed a sleep and/or sedation visit.
| Age, Continuous(years) | All Study Participants |
|---|---|
| Total | 23.44 ± 4.60 |
| Sleep | 25.13 ± 5.33 |
| Dexmedetomidine | 22.95 ± 3.75 |
| Ketamine | 21.47 ± 3.14 |
| Propofol | 22.83 ± 4.17 |
| Sex: Female, Male(Participants) | All Study Participants |
|---|---|
| Total — Female | 7 |
| Total — Male | 20 |
| Sleep — Female | 4 |
| Sleep — Male | 11 |
| Dexmedetomidine — Female | 6 |
| Dexmedetomidine — Male | 14 |
| Ketamine — Female | 5 |
| Ketamine — Male | 10 |
| Propofol — Female | 2 |
| Propofol — Male | 4 |
| Midazolam — Female | — |
| Midazolam — Male | — |
| Ethnicity (NIH/OMB)(Participants) | All Study Participants |
|---|---|
| Total — Hispanic or Latino | 2 |
| Total — Not Hispanic or Latino | 17 |
| Total — Unknown or Not Reported | 8 |
| Sleep — Hispanic or Latino | 1 |
| Sleep — Not Hispanic or Latino | 6 |
| Sleep — Unknown or Not Reported | 8 |
| Dexmedetomidine — Hispanic or Latino | 1 |
| Dexmedetomidine — Not Hispanic or Latino | 11 |
| Dexmedetomidine — Unknown or Not Reported | 8 |
| Ketamine — Hispanic or Latino | 1 |
| Ketamine — Not Hispanic or Latino | 7 |
| Ketamine — Unknown or Not Reported | 7 |
| Propofol — Hispanic or Latino | 0 |
| Propofol — Not Hispanic or Latino | 2 |
| Propofol — Unknown or Not Reported | 4 |
| Midazolam — Hispanic or Latino | — |
| Midazolam — Not Hispanic or Latino | — |
| Midazolam — Unknown or Not Reported | — |
| Race (NIH/OMB)(Participants) | All Study Participants |
|---|---|
| Total — American Indian or Alaska Native | 0 |
| Total — Asian | 1 |
| Total — Native Hawaiian or Other Pacific Islander | 1 |
| Total — Black or African American | 2 |
| Total — White | 15 |
| Total — More than one race | 0 |
| Total — Unknown or Not Reported | 8 |
| Sleep — American Indian or Alaska Native | 0 |
| Sleep — Asian | 1 |
| Sleep — Native Hawaiian or Other Pacific Islander | 1 |
| Sleep — Black or African American | 1 |
| Sleep — White | 4 |
| Sleep — More than one race | 0 |
| Sleep — Unknown or Not Reported | 8 |
| Dexmedetomidine — American Indian or Alaska Native | 0 |
| Dexmedetomidine — Asian | 1 |
| Dexmedetomidine — Native Hawaiian or Other Pacific Islander | 0 |
| Dexmedetomidine — Black or African American | 1 |
| Dexmedetomidine — White | 10 |
| Dexmedetomidine — More than one race | 0 |
| Dexmedetomidine — Unknown or Not Reported | 8 |
| Ketamine — American Indian or Alaska Native | 0 |
| Ketamine — Asian | 0 |
| Ketamine — Native Hawaiian or Other Pacific Islander | 0 |
| Ketamine — Black or African American | 0 |
| Ketamine — White | 8 |
| Ketamine — More than one race | 0 |
| Ketamine — Unknown or Not Reported | 7 |
| Propofol — American Indian or Alaska Native | 0 |
| Propofol — Asian | 0 |
| Propofol — Native Hawaiian or Other Pacific Islander | 0 |
| Propofol — Black or African American | 0 |
| Propofol — White | 2 |
| Propofol — More than one race | 0 |
| Propofol — Unknown or Not Reported | 4 |
| Midazolam — American Indian or Alaska Native | — |
| Midazolam — Asian | — |
| Midazolam — Native Hawaiian or Other Pacific Islander | — |
| Midazolam — Black or African American | — |
| Midazolam — White | — |
| Midazolam — More than one race | — |
| Midazolam — Unknown or Not Reported | — |
| Region of Enrollment(participants) | All Study Participants |
|---|---|
| United States | 27 |
Documents are hosted by the registry — open the source record to download them.
This study is completed, as verified in Apr 2023. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
University of Wisconsin, Madison