Pharmacokinetics-pharmacodynamics and Safety of Dexmedetomidine in Children

Study Overview
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Brief Summary
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This study evaluates pharmacokinetics and pharmacodynamics of dexmedetomidine for children under sedation at intensive care unit after surgery. Patients will receive dexmedetomidine intravenously for 50 minutes after surgery as as sedation drug.

Detailed Description
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Dexmedetomidine, an alpha-2 adrenergic agonist, is being effectively used for procedural sedation or sedation at intensive care unit. However, the safety and efficacy profile are not yet established for children. Although there have been some studies regrading it, still there is no public guideline, therefore making it difficult to use dexmedetomidine in children.

Official Title
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Pharmacokinetic-pharmacodynamic Analysis for Dosing Strategy and Evaluation of Safety and Efficacy of Dexmedetomidine in Children

Conditions
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Intensive Care Unit, Postoperative Care

Intervention / Treatment
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* Drug: Dexmedetomidine Hydrochloride


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Pediatric patients planned to undergo mechanical ventilation at intensive care unit after surgery Pediatric patients planned to be extubated within 4 hours after surgery for neurological examination Patients whose parent of legal guardian agreed to enroll in the study after having enough time to review the complete explanation about the study. Exclusion Criteria: History of hypersensitivity to any drugs including dexmedetomidine. Underlying cardiovascular/circulatory disease Underlying liver / kidney disease Patients under hemodialysis Obesity of BMI > 35 Patients planned to receive patient-controlled analgesia including opioids Patients whose parent or legal guardian declined to enroll in the study Other conditions deemed unsuitable for the study

Ages Eligible for Study
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Minimum Age: 7 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Intervention Model: Single Group Assignment
Interventional Model Description: Dexmedetomidine infusion at intensive care unit
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dexmedetomidine<br>Intravenous infusion of dexmedetomidine for 50 min after surgery at intensive care unit | Drug: Dexmedetomidine Hydrochloride<br>* Intravenous infusion of dexmedetomidine at the rate of 0.5mcg/kg for 10 min, then 0.5mcg/kg/hr for 50 min.<br>* Other names: Precedex;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma concentration of dexmedetomidine | Plasma concentration of dexmedetomidine before infusion, 10/30/60 minutes after initiation of infusion, 15/30/60/120/240/480 minutes after end of infusion | From start of dexmedetomidine infusion to 480 minutes after end of dexmedetomidine infusion | 
| Bispectral index | Bispectral index based on electroencephalogram during patient's stay at intensive care unit (0-100, lower score implies deeper sedation) | From start of dexmedetomidine infusion to 480 minutes after end of dexmedetomidine infusion | 
| University of Michigan Sedation Scale | University of Michigan Sedation Scale based on observer's inspection during patient's stay at intensive care unit (0-4, higher score implies deeper sedation) | From start of dexmedetomidine infusion to 480 minutes after end of dexmedetomidine infusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of arrhythmia | Presence of any kind of arrhythmia from electrocardiogram following dexmedetomidine infusion | From start of dexmedetomidine infusion to 24 hours after end of dexmedetomidine infusion | 
| Non-invasive blood pressure | Non-invasive blood pressure in units of mmHg, to examine whether hypertension (increase in blood pressure more than 20% of baseline) or hypotension (decrease in blood pressure more than 20% of baseline) occurs | From start of dexmedetomidine infusion to 24 hours after end of dexmedetomidine infusion | 
| Incidence of desaturation | Presence of desaturation (pulse oximetry of lower than 94%) following dexmedetomidine infusion | From start of dexmedetomidine infusion to 24 hours after end of dexmedetomidine infusion | 
| Respiratory rate | Respiratory rate in units of /min, to examine whether respiratory depression or apnea occurs | From start of dexmedetomidine infusion to 24 hours after end of dexmedetomidine infusion | 
| Incidence of nausea | Incidence of nausea following dexmedetomidine infusion | From start of dexmedetomidine infusion to 24 hours after end of dexmedetomidine infusion | 
| Incidence of vomiting | Incidence of vomiting following dexmedetomidine infusion | From start of dexmedetomidine infusion to 24 hours after end of dexmedetomidine infusion | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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dexmedetomidine, pediatric, sedation