Effect of OFA in Laparoscopic Gastrectomy

Study Overview
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Brief Summary
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The investigator will examine the effects of opioid free anesthesia in patients undergoing laparoscopic gastrectomy. The investigator expect that opioid free anesthesia will reduce postoperative pain and opioid consumption. And investigator will analyze the association between postoperative pain and patient's underlying psychological characteristics and pain sensitivity. The investigator anticipate that psychological characteristics and pain sensitivity may be realted to postoperative pain and opioid consumption.

Official Title
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Effect of Opioid Free Anesthesia in Patients Undergoing Laparoscopic Gastrectomy: Subgroup Analysis Based on Psychological Trait

Conditions
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Postoperative Pain

Intervention / Treatment
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* Drug: OFA
* Drug: Control


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients over 19 years who underwent laparoscopic gastrectomy for gastric cancer Exclusion Criteria: Patients with a history of allergic reactions to drugs Patients with a history of drug addiction Patients with chronic pain who require analgesics Patients with cancer other than the stomach History of hospitalization for psychiatric disorders Patients with sleep apnea Preoperative pulse oximetry (SpO2) < 95 % Moderate or severe hepatic impairment bradycardia (HR<50bpm), hypotension, atrioventricular block, intraventricular or sinus block Body mass index over 35 kg/m2 Blood clotting disorders Pregnant/lactating women Cognitive impairment Unable to read consent form (eg illiterate, foreigner, etc.)

Ages Eligible for Study
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Minimum Age: 19 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: OFA group<br>Dexmedetomidine and lidocaine are administered during anesthesia, and opioid is not used. For induction, 1 μg/kg of Dexmedetomidine is administered over 10 minutes and 1mg/kg of lidocaine is administered intavenously (bolus). This is followed by continuous intravenous infusion of dexmedetomidine at a rate of 0.2-0.7 μg/kg/h and infusion of lidocaine at the rate of 1 mg/kg/h. | Drug: OFA<br>* Dexmedetomidine and lidocaine are administered during anesthesia, and opioid is not used. For induction, 1 μg/kg of Dexmedetomidine is administered over 10 minutes and 1mg/kg of lidocaine is administered intavenously (bolus). This is followed by continuous intravenous infusion of dexmedetomidine at a rate of 0.2-0.7 μg/kg/h and infusion of lidocaine at the rate of 1 mg/kg/h.<br>|
| Active Comparator: Control group<br>Remifentanil is infused during anesthesia, and target-controlled infusion (TCI) is performed according to the Minto model. During indcution of anestheisa, target concentration of remifentanil is set within 3-5 ng/mL. After intubation, target concentration is adjusted within the range of 2-8 ng/mL. | Drug: Control<br>* Remifentanil is infused during anesthesia, and target-controlled infusion (TCI) is performed according to the Minto model. During indcution of anestheisa, target concentration of remifentanil is set within 3-5 ng/mL. After intubation, target concentration is adjusted within the range of 2-8 ng/mL.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Opioid consumption in postoperative 24hrs | Total opioid dose administered to the patient. | 24 hours after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Opioid consumption | Total opioid dose administered to the patient. | postoperative 6hours, 12hours, 36hours, 48hours, 3days, 4days, 5days | 
| Time to bowel function recovery (Gas passing time, Fluid intake start time, Soft diet start time) | Time (hours) to first gas passing / starting oral fluid intake / starting soft diet | up to 2weeks | 
| Pain score | verbal numerical rating scale 0-10 | postoperative 6hours, 12hours, 24hours, 36hours, 48hours, 3days, 4days, 5days, 2weeks | 
| Nausea score | verbal numerical rating scale 0-10 | postoperative 6hours, 12hours, 24hours, 36hours, 48hours, 3days, 4days, 5days | 
| Time to rescue analgesics after surgery | Time (hours) to first rescue analgesics | up to 2weeks | 
| Number of vomiting, antiemetic adeministration | Number of vomiting, antiemetic adeministration | up to 2weeks | 
| Hemodynamics during surgery | changes in hemodyanamics during surgery | during surgery | 
| QoR-15 | Score of QoR-15 questionnaire (Quality of Recovery-15)(Minimum value: 0, Maximum value: 150, higher scores means better.) | 1-5 days before surgery, postoperative 1day, postoperative 4day | 
| PCL-5 | Score of PCL-5 (Posttraumatic stress disorder Checklist for DSM-5) (Minimum value: 0, Maximum value: 80, higher scores means worse.) | postoperative 1week |