Comparison of Dexmedetomidin and Remifentanil for the Effect on Airway Reflex and Hemodynamic Response During Emergence in Patients Undergoing Craniotomy

Study Overview
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Brief Summary
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During recovery from general anesthesia the stimuli of endotracheal tube lead to the coughing, hypertension, tachycardia, which can cause a serious complication. Especially the postoperative course of patients emerging from general anesthesia after intracranial surgery is frequently complicated by the occurrence of hypertension and coughing event. It has been demonstrated that opioid, intravenous or topical lidocaine administration can attenuate the coughing reflex. Administered the opioid before emergence, it is effective to prevent cough reflex but the recovery is delayed, it was difficult to predict emergence. However, remifentanil is an opioid widely used because of rapid context-sensitive half-life, target-controled infusion method to adequately maintain the effect site concentration could help to predict the recovery time to the alert state from the general anesthesia. It is considered proper method of continuous infusion of remifentanil for reducing emergence cough. Dexmedetomidine , a potent alpha adrenoceptor agonist which dose-dependently reduces arterial blood pressure and heart rate, decreases the hemodynamic and and catecholamine response to intubation and extubation. It is thus theologically appropriate for reducing airway and circulatory reflexes during emergence from anesthesia. In this study, the investigators used bolus dexmedetomidine immediately before extubation, and compared the effects on coughing, hemodynamic response and recovery profile to a continuous infusion of remifentanil.

Official Title
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Comparison of Dexmedetomidin and Remifentanil for the Effect on Airway Reflex and Hemodynamic Response During Emergence in Patients Undergoing Craniotomy

Conditions
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Open Craniotomy

Intervention / Treatment
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* Drug: remifentanil
* Drug: dexmedetomidine with remifentanil


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: SA I II, 2.aged between 20 and 70 year, 4.general anesthesia for craniectomy Exclusion Criteria: signs of an anatomical or functional abnormality in upper airway URI or sore throat for recent 2 weeks Congestive heart failure, Sinus Bradycardia(<50 BPM), Uncontrolled hypertension Chronic obstructive lung disease, bronchial asthma

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 70 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Remifentanil group<br>Remifentanil group : remifentanil effect site-TCI 2-4ng/ml | Drug: remifentanil<br>* remifentanil effect site-TCI 2-4ng/ml<br>|
| Active Comparator: Dexmedetimidine group<br>Dexmedetomidine group: remifentanil effect site-TCI 2-4ng/ml + dexmedetomidine 0.5mcg/kg | Drug: dexmedetomidine with remifentanil<br>* remifentanil effect site-TCI 2-4ng/ml with dexmedetomidine 0.5mcg/kg<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| cough incidence |  | 1 minute after extubation |