Characterizing the Neuropharmacology of Dexmedetomidine Through Trimodal Imaging
试验速览
- 阶段
- 早期 1 期
- 入组人数
- 30
- 试验地点
- 1
- 主要终点
- Functional magnetic resonance imaging (fMRI) signals.
研究概览
简要总结
The investigators will be studying the sedative drug dexmedetomidine using hybrid PET/fMRI/EEG imaging to better understand the neuropharmacology of anesthesia/artificially induced sleep.
详细描述
A group of healthy volunteers will undergo simultaneous PET/fMRI/EEG imaging under two different conditions: while being administered a sedative (dexmedetomidine), and while being administered a normal saline infusion, as a control. The order of these two scans will be randomized, and the study design is open label (ie subjects and investigators know which session will be the control scan and which one will be the sedative scan). Investigators hope that by comparing the results of the sedative and control scans, the different neuromodulatory states involved in the transition from wakefulness to medically induced vs naturally occurring sleep can be better understood.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 45 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Adults aged 18-
- •No contraindications to MRI or PET scanning.
排除标准
- •Contraindications to fMRI scanning and PET scanning (including presence of a cardiac pacemaker or pacemaker wires, metallic particles in the body, vascular clips in the head or previous neurosurgery, prosthetic heart valves, claustrophobia);
- •Pregnancy or breast feeding;
- •Current or past history of major medical, neurological, or psychiatric condition;
- •History of major head trauma;
- •Any cardiovascular disorders, including heart disorders or high blood pressure [>155/95];
- •Breathing problems such as severe asthma;
- •Bleeding disorder, or use of anticoagulants;
- •Bladder obstruction, urinary problems, or history of impaired elimination;
- •Known kidney or liver problems;
- •Intestinal blockage;
- •Raynaud syndrome
- •Peripheral nerve injury;
- •Diabetes;
- •Glaucoma;
- •Sleep disorder, such as sleep apnea, insomnia, or narcolepsy
- •Current use of any drugs that affect sleep
- •Current or recent use of medications (neurological or psychiatric) affecting brain function
- •Current or past history of chronic pain (assessed at discretion of PI);
- •History of allergic reactions
- •History of chronic obstructive pulmonary diseases
- •Ulcerative skin conditions or other dermatologic conditions which could interfere with blood pressure cuff placement
- •Body mass index above 30
- •Current smoker
- •Lack of current health insurance coverage
- •Employed under the direct supervision of the investigators conducting the research
- •Hair in dreadlocks, twists, or braids that cannot be removed
- •Eczema on the scalp or face
研究组 & 干预措施
Dexmedetomidine
During the imaging scan subjects will receive an initial 1µg/kg bolus of dexmedetomidine up to a maximum dose of 80 µg, infused through IV over 10 minutes. After the bolus has been administered, a constant infusion of up to 0.6 µg/kg/hr (0.01 µg/kg/min) of dexmedetomidine will be maintained for the remainder of the scan (about 60 minutes).
干预措施: Dexmedetomidine (Drug)
Saline
A saline infusion will be used as a placebo comparator for the dexmedetomidine infusion. It will be administered in the same manner and dosages as the dexmedetomidine.
干预措施: Saline (Drug)
结局指标
主要结局
Functional magnetic resonance imaging (fMRI) signals.
时间窗: 2 hours
fMRI measures of hemodynamic responses.
Differences in electroencephalography (EEG) measures between arousal and anesthesia.
时间窗: 2 hours
Arousal states will be characterized from changes in the EEG power spectrum.
Brain positron emission tomography (PET) imaging signals.
时间窗: 2 hours
Changes in dopamine receptor availability will be quantified from brain PET images.
次要结局
- Respiratory physiology(2 hours)
- Heart rate(2 hours)
- Pulse oximetry(2 hours)
研究者
Christin Y. Sander, PhD
Dr Christin Sander, Assistant Professor
Massachusetts General Hospital