The Effect of Thoracic Epidural Anesthesia With Different Block Level on Propofol Induction

Study Overview
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Brief Summary
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It is a prospective, randomized, placebo-controlled study to investigate the effect of TEA with different block level on propofol concentration during general anesthesia induction.

Official Title
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The Effect of Thoracic Epidural Anesthesia With Different Block Level on Propofol Concentration During General Anesthesia Induction

Conditions
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Target Controlled Infusion (TCI), Thoracic Epidural Anesthesia, Block Level, Gastrointestinal Surgery

Intervention / Treatment
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* Drug: 1% lidocaine
* Drug: 2% lidocaine
* Drug: 0.9% normal saline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologists (ASA) I-II physical status, aged 40-60 yr, BMI 19-25 kg/m2, undergoing elective gastrointestinal surgery Exclusion Criteria: patients with cardiovascular or neurological disease, drug or alcohol abuse and absolute contraindications for neuraxial blockade.

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 60 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1% lidocaine<br>epidural anesthesia with 1% lidocaine 10ml before propofol TCI | Drug: 1% lidocaine<br>* epidural anesthesia with 1% lidocaine 10ml before propofol TCI<br>* Other names: A;|
| Experimental: 2% lidocaine<br>epidural anesthesia with 2% lidocaine 5ml before propofol TCI | Drug: 2% lidocaine<br>* epidural anesthesia with 2% lidocaine 5ml before propofol TCI<br>* Other names: B;|
| Placebo Comparator: 0.9% normal saline<br>epidural anesthesia with 0.9% normal saline 5ml before propofol TCI | Drug: 0.9% normal saline<br>* epidural anesthesia with 0.9% normal saline 5ml before propofol TCI<br>* Other names: C;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Effect-site Concentration of Propofol | The effect-site concentration of propofol when loss of consciousness during propofol target-controlled infusing(TCI) induction of anesthesia. | The participants will be followed for the duration of anesthesia induction, an expected average of half an hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Bispectral Index | The bispectral index (BIS) of each patient will be recorded at four different time points,as follows, baseline(the awake phase before epidural anesthesia),10 mins after epidural anesthesia, 20 mins after epidural anesthesia, loss of consciousness(when the participants are lost eyelash reflex during propofol TCI induction of anesthesia). BIS values varies from 0 to 100(0, no cerebral activity; 40 to 60, general anesthesia; 60 to 85, sedated; 85 to 100, awake). | The participants will be followed for the duration of anesthesia induction, an expected average of half an hour | 
| The Mean Blood Pressure | The mean arterial pressure of each patient will be recorded at four different time points, as follows, baseline(the awake phase before epidural anesthesia), 10 mins after epidural anesthesia, 20 mins after epidural anesthesia, loss of consciousness(when the participants are lost eyelash reflex during propofol TCI induction of anesthesia). | The participants will be followed for the duration of anesthesia induction, an expected average of half an hour | 
| The Heart Rate | The heart rate of each patient will be recorded at three different four points, as follows, baseline(the awake phase before epidural anesthesia), 10mins after epidural anesthesia, 20 mins after epidural anesthesia, loss of consciousness(when the participants are lost eyelash reflex during propofol TCI induction of anesthesia). | The participants will be followed for the duration of anesthesia induction, an expected average of half an hour | 
| The Block Level of Epidural Anesthesia | The block level 20mins after epidural anesthesia and it is verified by the loss of sensation to alcohol swab before target controlled infusion of propofol.It is the number of block segments.The block level varies from 0 to 10(0, no block level; 1 to 5, narrow block level;6 to 10, wide block level). | 20 mins after epidural anesthesia | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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effect-site concentration, propofol, thoracic epidural anesthesia