Neuroimaging Study of Dexmedetomidine-Induced Analgesia

Study Overview
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Brief Summary
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Neuroimaging data will be collected for patients that are given low doses of dexmedetomidine in order to understand its analgesic effects.

Detailed Description
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In this trial, participants will be given dexmedetomidine using a single-arm study design. fMRI will be conducted during this time. Cognitive assessments and pain monitoring will be administered at various points before and after dexmedetomidine is administered.

Official Title
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Neuroimaging Study of Dexmedetomidine-Induced Analgesia

Conditions
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Analgesia, Anesthesia

Intervention / Treatment
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* Drug: Dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Between the ages of 18 to 45 Normal body weight and habitus, BMI ≤ 30 Non-smoker American Society of Anesthesiologists (ASA) physical status classification P1 Active health insurance coverage Fully vaccinated against COVID-19 Exclusion Criteria: Cardiovascular: myocardial infarction, coronary artery disease, peripheral vascular disease, arrhythmia, congestive heart failure, valvular disease, hypertension Respiratory: bronchitis, chronic obstructive pulmonary disease, smoking, shortness of breath Hepatic: hepatitis, jaundice, ascites Neurologic: seizure, stroke, positive neurologic findings on neurologic examination, multiple sclerosis, Meniere's disease, Parkinson's disease, neuropathy, peripheral stenosis Gastrointestinal: esophageal reflux, hiatal hernia, ulcer Endocrine: diabetes, thyroid disease Renal: acute or chronic severe renal insufficiency Hematologic: blood dyscrasias, anemia, coagulopathies, on anticoagulant therapy Musculoskeletal: prior surgery or trauma to head neck or face, arthritis, personal or family history of malignant hyperthermia Psychiatric: history or treatment for an active psychiatric problem, depression Reproductive: pregnancy, breast-feeding Medications: regular use of prescription and non-prescription medications expected to affect CNS function, St. John's Wort Allergies: dexmedetomidine, ondansetron, glycopyrrolate, phenylephrine Dermatologic: ulcerative skin conditions or other dermatologic conditions which could interfere with blood pressure cuff placement. MRI reasons for exclusion: History of head trauma, surgical aneurysm clips, cardiac pacemaker, prosthetic heart valve, neurostimulator, implanted pumps, cochlear implants, metal rods, plates, or screws, intrauterine device, hearing aid, dentures, metal injury to eyes, metallic tattoos anywhere on the body or near the eye.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Interventional Model Description: Patients will receive dexmedetomidine anesthesia during the study visit.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dexmedetomidine<br>During the study visit, patients will be delivered dexmedetomidine anesthesia. 0.5mcg/kg of dexmedetomidine solution will be infused over 10 minutes, and then up to 0.5mcg/kg/hr will be maintained for an additional 20-30 minutes. | Drug: Dexmedetomidine<br>* Patients will be delivered dexmedetomidine anesthesia to gain greater understanding of its analgesic effects.<br>* Other names: Precedex;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effect of Dexmedetomidine on Pain Processing Circuitry | fMRI data will be used to compare changes in brain connectivity due to pain using functional network and seed-based correlation analyses when a pain cuff (Hokanson Rapid Cuff Inflator) is inflated during baseline and dexmedetomidine analgesia periods. | Change in brain functional connectivity between baseline pain and dexmedetomidine pain during the fMRI visit, an average of 90 minutes |