The Effect of Dexmedetomidine on Hemodynamic Response During Double Lumen Endotracheal Intubation

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the effect of dexmedetomidine on hemodynamic responses during laryngoscopy and double lumen endotracheal intubation and assess the adverse effect related to complications of dexmedetomidine.

Detailed Description
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The cardiovascular responses to laryngoscopy and tracheal intubation are mediated by both sympathetic and parasympathetic nervous system. The hemodynamic responses resulting from sympathetic nervous system stimulation are tachycardia, cardiac arrhythmias, hypertension, increased intraocular pressure, increased intracranial pressure, bronchospasm and myocardial ischemia. Tachycardia is one of the major predictor of intraoperative myocardial ischemia and causes an imbalance of myocardial oxygen supply and demand. Although hemodynamic responses to laryngoscopy and intubation is transient, these effect may be harmful to patients suffering from myocardial and cerebrovascular diseases. The placement of double lumen endotracheal tube may produce similar or greater pressor response than endotracheal tube because of larger sizes and greater carinal stimulation.

Official Title
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The Effect of Prophylactic Dexmedetomidine on Hemodynamic Disturbances During Double Lumen Endotracheal Intubation. A Double-blinded, Randomized, Placebo-Controlled Trial.

Conditions
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Intubation Complication, Tracheal Intubation Morbidity, Anesthesia Intubation Complication, Hypertension, High Blood Pressure, Tachycardia

Intervention / Treatment
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* Drug: Dexmedetomidine
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA Physical Status I-III Undergoing Elective Thoracotomy or Thoracoscopy Required Left Sided-double Lumen Endotracheal Intubation Exclusion Criteria: Patients with bradycardia (heart rate < 50 beat per minute) or heart block Suspected of Difficult Intubation Patients Who Are at Risk for Rapid Change of Hemodynamics Allergic to Dexmedetomidine Hepatic or Renal Impairment (Preoperative Serum Creatinine > 1.5 mg/dl) Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: dexmedetomidine<br> | Drug: Dexmedetomidine<br>* dexmedetomidine 0.7 microgram per kilogram in saline 20 ml given within 10 minutes before intubation<br>* Other names: Precedex;|
| Placebo Comparator: control<br> | Drug: Placebo<br>* normal saline 20 ml( the same volume as dexmedetomidine) giving within 10 minutes.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in systolic blood pressure | direct arterial pressure monitoring | (day 1) before induction, before intubation and every minute for the first 10 minutes after endotracheal intubation | 
| change in diastolic blood pressure | direct arterial pressure monitoring | (day 1) before induction, before intubation and every minute for the first 10 minutes after endotracheal intubation | 
| change in mean arterial pressure | direct arterial pressure monitoring | (day 1) before induction, before intubation and every minute for the first 10 minutes after endotracheal intubation | 
| change in heart rate |  | (day 1) before induction, before intubation and every minute for the first 10 minutes after endotracheal intubation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| adverse events related to dexmedetomidine | bradycardia, hypotension, arrhythmia | (day 1) during dexmedetomidine administration until 10 minutes after endotracheal intubation |