A Comparison of Dexmedetomidine and Epidural Anesthesia Under General Anesthesia in Patients Undergoing Gastrectomy

Study Overview
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Brief Summary
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Clinically, combining epidural with general anaesthesia may confer many advantages to patients undergoing major thoracic, abdominal or orthopaedic surgery. Epidural anaesthesia can attenuate sympathetic hyperactivity and the stress response, maintain bowel peristalsis, spare the use of opioids, and facilitate postoperative feeding and physiotherapy. However, establishing epidural anesthesia is not without risks and contraindications, including refusal by the patient, technical failure, unintentional dural puncture, waist and back pain and local anaesthetic toxicity. When neurologic complications do occur, the resulting morbidity and mortality is considerable. Dexmedetomidine is a potent α2-adrenoceptor agonist with an 8 times greater affinity for α2-adrenoceptors than clonidine. This class of agent is known to have sedative, anxiolytic, anti-shivering, analgesic, and anaesthetic sparing effect. In addition α2-adrenoceptor agonists reduce central sympathetic outflow and attenuate the stress response associated with surgery.1 Unlike epidural anaesthesia, dexmedetomidine is easy to administer and no potential for neurological damage. The investigators hypothesize that the dexmedetomidine reduces the stress response of surgery to the similar extent to epidural anaesthesia when used in conjunction with a standard general anaesthesia for abdominal surgery.

Official Title
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A Comparison of Dexmedetomidine and Epidural Anesthesia Under General Anesthesia in Patients Undergoing Gastrectomy

Conditions
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Gastrectomy

Intervention / Treatment
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* Drug: dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Consent ASA 1-2 No contraindication to epidural or dexmedetomidine First time surgery for current conditions Not on chronic pain medications or sedative Exclusion Criteria: .The subject has known significant renal or hepatic disorders determined by medical history, physical examination or laboratory tests The subject has a known or suspected allergy to opioid analgesics or dexmedetomidine The subject has history of. cardiovascular issues which would preclude the use of dexmedetomidine The subject has know central nervous system disease or neurological impairment The subject is an ASA classification of 3 or greater

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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: dexmedetomidine<br>Drug:dexmedetomidine,dexmedetomidine 1.0μg/kg intravenous injection within 15 minutes before the induction of general anesthesia and followed by Dex 0.4μg/kg/h until 40min before the end of surgery | Drug: dexmedetomidine<br>* Dexmedetomidine, an alpha 2 agonist provides sedative, anxiolytic, anti-shivering, analgesic, and anaesthetic sparing effect. In addition α2-adrenoceptor agonists reduce central sympathetic outflow and attenuate the stress response associated with surgery.Unlike epidural anaesthesia, dexmedetomidine is easy to administer and no potential for neurological damage. Date suggest that the dexmedetomidine reduces the stress response of surgery to the similar extent to epidural anaesthesia when used in conjunction with a standard general anaesthesia for abdominal surgery.<br>* Other names: epidural;|
| Active Comparator: epidural<br>Epidural:continuous epidural block (T8-9) 4 mL of 1.6% lidocaine as a test dose and continous infusion of 0.375% ropivacaine(5 mL/h) during the surgery | Drug: dexmedetomidine<br>* Dexmedetomidine, an alpha 2 agonist provides sedative, anxiolytic, anti-shivering, analgesic, and anaesthetic sparing effect. In addition α2-adrenoceptor agonists reduce central sympathetic outflow and attenuate the stress response associated with surgery.Unlike epidural anaesthesia, dexmedetomidine is easy to administer and no potential for neurological damage. Date suggest that the dexmedetomidine reduces the stress response of surgery to the similar extent to epidural anaesthesia when used in conjunction with a standard general anaesthesia for abdominal surgery.<br>* Other names: epidural;|
| Placebo Comparator: control<br>Drug: normalsaline | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiovascular Parameters: Heart rate, blood pressure and ECG ;Parameters on stress response:norepinephrine (NE), epinephrine ( E) |  | pre-administration of Dex or epidural anesthesia,intubation, 3 min after intubation , immediately after incision, immediately after the initiation of celiac exploration, 1 h after operation,extubation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Anesthetics consumption: propofol and remifentanil consumption |  | during operation | 
| anesthesia recovery :the time of eye opening, side effects such as nausea, vomiting and post-anaesthetic shivering, VAS, first exhaust time, hospitalization time |  | up to 48 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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dexmedetomidine, Epidural Anesthesia, stress response, anesthesia recovery