A Phase 1 interventional study of Dexmedetomidine and Midazolam in Amnesia, Pain and Anesthesia, sponsored by University of Pittsburgh. Completed at 1 site in United States. Open to participants aged 18 Years to 39 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2020-07-01.
Sponsored by University of Pittsburgh · Phase 1, Interventional, and Basic science
The purpose of this study is to determine the effects of pain on facilitating long-term auditory memory in the presence and absence of distinct intravenous anesthetics. The ability to identify previously presented words from a list assessed the degree of memory formation. In a subset of subjects, functional magnetic resonance imaging was used to identify the neural correlates of memory inhibition or facilitation by the combination of pain and anesthetic used.
This study adds specific details to the current incomplete body of knowledge examining the effect of pain on memory formation under the influence of anesthetic agents.
Pain and anesthetic agents were administered as experimental variables in this study. Healthy adult subjects were played repeated lists of words and performed several decision-making tasks that encourage memory encoding. Some words were consistently paired with painful electric shock, and was anticipated to improve subsequent memory performance specifically for those items. The same experiment was repeated in all subjects during the administration of 1-2 possible agents that reduce memory formation: dexmedetomidine, a predominantly sedative agent, and midazolam, a well-known amnestic agent, and ketamine, a well-known dissociative analgo-sedative. The extent to which pain modulates memory performance under the effects of the anesthetic agents was the primary outcome of interest.
Further, a subset of the subjects performed the same experimental procedures while undergoing functional magnetic resonance imaging, which continuously reflects neuronal activity throughout the brain. Classic memory areas were predicted to be activated by the auditory processing task, but how these neural circuits change under the two anesthetic agents with the concomitant experience of pain were of interest. It was anticipated that pain recruits a parallel memory pathway using limbic structures, known for their involvement in fear conditioning. Additionally, stronger and more diffuse cortical processing likely occurs with concomitant pain, as level of sedation was reduced by this strong stimulus. Discovering the anatomic correlates specific to each experimental variable (pain and anesthetic), and their interplay, may help refine our model of brain function during the dynamics of pain and sedation.
22 studies on the registry are indexed under Amnesia; 2 are open to participants now.
This study's enrollment of 32 is below the median of 62 across 19 interventional studies indexed under Amnesia.
Browse Amnesia studies →University of Pittsburgh is the lead sponsor of 1,419 studies on the registry; 168 are open to participants now.
Of its 9 completed or terminated interventional studies of FDA-regulated products, 4 (44%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
All subjects receive saline (control), followed by a dexmedetomidine infusion. They also experience intermittent experimental pain delivered by peripheral nerve stimulation.
Drug: Dexmedetomidine · Device: Peripheral nerve stimulation
Subjects receive saline (control), followed by midazolam infusion. They also experience intermittent experimental pain delivered by peripheral nerve stimulation.
Drug: Midazolam · Device: Peripheral nerve stimulation
All subjects receive saline (control), followed by ketamine infusion. They also experience intermittent experimental pain delivered by peripheral nerve stimulation.
Device: Peripheral nerve stimulation · Drug: Ketamine
All subjects receive saline (control), followed by midazolam infusion. They also experience intermittent experimental pain delivered by peripheral nerve stimulation. Subjects then returned at least 1 week later for another set of experimental sessions with the same design, however the saline was followed by ketamine infusion.
Drug: Midazolam · Device: Peripheral nerve stimulation · Drug: Ketamine
All subjects receive saline (control), followed by ketamine infusion. They also experience intermittent experimental pain delivered by peripheral nerve stimulation. Subjects then returned at least 1 week later for another set of experimental sessions with the same design, however the saline was followed by midazolam infusion.
Drug: Midazolam · Device: Peripheral nerve stimulation · Drug: Ketamine
Selected subjects received this drug during a portion of the study
Also known as: Precedex
Selected subjects received this drug during a portion of the study
Also known as: Versed
Experimental acute pain stimulus was delivered using a nerve stimulator. These painful shocks were paired randomly with some of the auditory experimental cues.
Also known as: electric nerve stimulation
Selected subjects received this drug during a portion of the study
Also known as: Ketalar
Memory Testing
Subjects completed the Remember, Know, New (RKN) task during next day testing. Their d' memory score was calculated based on their ability to discriminate between previously heard words and new words. A higher d' score indicates stronger recollection. D' scores were compared across the control condition (saline) and the drug conditions dexmedetomidine, midazolam, and ketamine. Performance was also calculated according to words associated with Pain and No Pain conditions.
Time frame: At memory testing 1 day later
| Milestone | Dexmedetomidine | Midazolam | Ketamine | Drug Order A | Drug Order B |
|---|---|---|---|---|---|
| Started | 7 | 4 | 5 | 8 | 8 |
| Completed | 7 | 4 | 5 | 8 | 8 |
| Not completed | 0 | 0 | 0 | 0 | 0 |
Subjects completed the Remember, Know, New (RKN) task during next day testing. Their d' memory score was calculated based on their ability to discriminate between previously heard words and new words. A higher d' score indicates stronger recollection. D' scores were compared across the control condition (saline) and the drug conditions dexmedetomidine, midazolam, and ketamine. Performance was also calculated according to words associated with Pain and No Pain conditions.
| d' score | Dexmedetomidine | Midazolam | Ketamine | Saline |
|---|---|---|---|---|
| All Conditions | 1.20 ± .27 | .56 ± .05 | .82 ± .07 | 1.18 ± .07 |
| No Pain Condition | 1.12 ± .35 | .55 ± .06 | .85 ± .11 | 1.18 ± .10 |
| Pain Condition | 1.28 ± .43 | .57 ± .06 | .78 ± .10 | 1.10 ± .10 |
Collected over up to 18 days after the final experimental session. Non-serious events are listed at a 3.70% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Dexmedetomidine Only | 0/7 (0%) | 0/7 (0%) | 0/7 (0%) |
| Midazolam Only | 0/4 (0%) | 0/4 (0%) | 0/4 (0%) |
| Ketamine Only | 0/5 (0%) | 0/5 (0%) | 1/5 (20%) |
| Drug Order A | 0/8 (0%) | 0/8 (0%) | 1/8 (12.5%) |
| Drug Order B | 0/8 (0%) | 0/8 (0%) | 1/8 (12.5%) |
| Event | Dexmedetomidine Only | Midazolam Only | Ketamine Only | Drug Order A | Drug Order B |
|---|---|---|---|---|---|
| Nausea and vomitingGastrointestinal disorders | 0/7 | 0/4 | 1/5 | 1/8 | 0/8 |
| DysphoriaPsychiatric disorders | 0/7 | 0/4 | 0/5 | 0/8 | 1/8 |
| Age, Categorical(Participants) | Dexmedetomidine Only | Midazolam Only | Ketamine Only | Drug Order A | Drug Order B | Total |
|---|---|---|---|---|---|---|
| <=18 years | 0 | 0 | 0 | 0 | 0 | 0 |
| Between 18 and 65 years | 7 | 4 | 5 | 8 | 8 | 32 |
| >=65 years | 0 | 0 | 0 | 0 | 0 | 0 |
| Sex: Female, Male(Participants) | Dexmedetomidine Only | Midazolam Only | Ketamine Only | Drug Order A | Drug Order B | Total |
|---|---|---|---|---|---|---|
| Female | 3 | 2 | 1 | 3 | 5 | 14 |
| Male | 4 | 2 | 4 | 5 | 3 | 18 |
| Race and Ethnicity Not Collected(Participants) | Dexmedetomidine Only | Midazolam Only | Ketamine Only | Drug Order A | Drug Order B | Total |
|---|---|---|---|---|---|---|
| Count of participants | — | — | — | — | — | 0 |
| Region of Enrollment(participants) | Dexmedetomidine Only | Midazolam Only | Ketamine Only | Drug Order A | Drug Order B | Total |
|---|---|---|---|---|---|---|
| United States | 7 | 4 | 5 | 8 | 8 | 32 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — Data will be published. After all analysis and dissemination is complete, functional images will be shared via data repository.
Ran from Nov 2015 to primary completion in Dec 2018, 36 months.
Results were first posted in Jul 2020, 1 year 6 months after primary completion.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Jun 2020. 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.
Studies of the drugs tested here: Dexmedetomidine · Midazolam · Ketamine