Evaluation of the Stress Response in Bariatric Surgery With and Without the Use of Opioids

The goal of this clinical trial is to compare Opioid Free and Opioid Based Anaesthesia in patients undergoing sleeve gastrectomy. The main questions it aims to answer are:

• Will the total dose of intraoperative opioid be reduced?
• Will there be difference in pain scores between groups? Participants will be managed with the Nociceptive Level Index algorithm to guide intraoperative analgesia.

The Opioid Free Anaesthesia Group will be administered the Multimix infusion (Magnesium sulfate, dexmedetomidine, ketamine). The Opioid Based Anaesthesia Group will receive fentanyl as a bolus dose and remifentanil infusion.

Rescue fentanyl bolused will be injected as appropriate according to nociceptive level (NOL) values.

Study Overview

• Status: Recruiting
• Conditions: Bariatric Surgery Candidate; Opioid Use, Unspecified
• Intervention / Treatment: Drug: Opioid based anesthesia; Drug: Opioid Free Anaesthesia

Detailed Description

Opioid Free Anaesthesia has attracted the attention of clinicians since the outbreak of the opioid pandemic in the USA. It has been correlated with less intraoperative and postoperative opioid use. The Nociceptive Level Index algorithm allows for intraoperative monitoring of the nociceptive pathways and targeted pain management. Furthermore, it is known that morbidly obese patients may benefit from opioid sparing techniques.

Our aim is to investigate the effect of Opioid Free versus Opioid Based Anesthesia on postoperative pain in patients undergoing sleeve gastrectomy.

In this randomized, double blind clinical trial, patients will be allocated into two groups based on intraoperative pain management. Apart from recording postoperative pain scores, blood samples will be collected intraoperatively to evaluate the stress response among the two groups.

• Study Type: Interventional
• Enrollment (Estimated): 70
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Greece
  • Athens, Greece, 11527
    • Recruiting
    • G.Gennimatas General Hospital
    • Contact: Panagiotis Chatzistavridis, MD, MSc; Phone Number: +306972871556; Email: p_chatzistavridis@yahoo.gr
    • Contact: Kassiani Theodoraki, Dr; Email: ktheod@med.uoa.gr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age >18y and <75y
• morbid obesity confirmed diagnosis
• American Society of Anesthesiologists (ASA) II-III
• elective laparoscopic sleeve gastrectomy surgery
• signed informed consent

Exclusion Criteria:

• bradycardia, bundle branch block, hypotension, postural hypotension
• obstructive sleep apnoea
• history of depression
• chronic corticosteroid use or intraoperative administration of more than 8mg of prednisolone or equivalent
• refusal to participate

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Opioid Based Anaesthesia; This arm will receive: 2 mcg/kg fentanyl in 10 ml volume; 0.2 mL/kg/h remifentanil infusion; 0.1 mg/kg morphine	Drug: Opioid based anesthesia; 2 mcg/kg fentanyl in 10 ml volume; 0.2 mL/kg/h remifentanil infusion; 0.1 mg/kg morphine. Except for standard analgesic strategies, both groups will receive fentanyl as a rescue dose (1mcg/kg) based on a nociceptive level value > 25 or elevation of Heart Rate and/or Blood Pressure >20%. Placebo infusions of normal saline will be prepared to enable blinding.
Active Comparator: Opioid Free Anaesthesia; This arm will receive; 40 mg/kg magnesium sulfate in 100 ml N/S infusion; 0.4 mcg/kg dexmedetomidine, max total dose 50mcg in 50 ml N/S infusion; 0.3 mg/kg ketamine in 10 ml volume; 0.2 ml/kg of the Multimix regimen in 100 ml N/S infusion as a bolus (The Multimix regimen consists of 50mcg dexmedetomidine, 500 mg lidocaine and 50mg ketamine).; 0.2 ml/kg/h of the Multimix regimen in 100 ml N/S infusion as a continuous infusion	Drug: Opioid Free Anaesthesia; 40 mg/kg magnesium sulfate in 100 ml N/S infusion; 0.4 mcg/kg dexmedetomidine, max total dose 50mcg in 50 ml N/S infusion; 0.3 mg/kg ketamine in 10 ml volume; 0.2 ml/kg of the Multimix regimen in 100 ml N/S infusion as a bolus (The Multimix regimen consists of 50mcg dexmedetomidine, 500 mg lidocaine and 50mg ketamine).; 0.2 ml/kg/h of the Multimix regimen in 100 ml N/S infusion as a continuous infusion. Except for standard analgesic strategies, both groups will receive fentanyl as a rescue dose (1mcg/kg) based on a nociceptive level value > 25 or elevation of Heart Rate and/or Blood Pressure >20%. Placebo infusions of normal saline will be prepared to enable blinding.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative Visual Analogue Scale (VAS) score	The patient will be interviewed regarding postoperative pain using Visual Analogue Scale, ranging from 0 to 10, where 0 means "no pain" and 10 means "worst pain imaginable	6 hours after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
First demand for supplementary analgesia	The time to the first demand for supplementary analgesia will be recorded for every patient enrolled.	Up to 24 hours postoperatively
Postoperative VAS score	The patient will be interviewed regarding postoperative pain using Visual Analogue Scale, ranging from 0 to 10, where 0 means "no pain" and 10 means "worst pain imaginable	24 hours
Perioperative trend of Adrenaline	Blood will be collected to measure the plasma adrenaline levels	At baseline, at the end of the operation, 24 hours after surgery
Perioperative trend of Noradrenaline	Blood will be collected to measure the plasma Noradrenaline levels	At baseline, at the end of the operation, 24 hours after surgery
Perioperative trend of Cortisol	Blood will be collected to measure the plasma Cortisol levels	At baseline, at the end of the operation, 24 hours after surgery
Perioperative trend of Dopamine	Blood will be collected to measure the plasma Dopamine levels	At baseline, at the end of the operation, 24 hours after surgery

Collaborators and Investigators

• Sponsor: G.Gennimatas General Hospital
• Collaborators: Aristotle University Of Thessaloniki

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2023
• Primary Completion (Estimated): May 28, 2026
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: February 11, 2023
• First Submitted That Met QC Criteria: February 21, 2023
• First Posted (Actual): March 3, 2023

Study Record Updates

• Last Update Posted (Actual): April 28, 2026
• Last Update Submitted That Met QC Criteria: April 25, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: bariatric surgery; analgesia; morbid obesity; opioid free anaesthesia; nociception level
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Nutrition Disorders; Overnutrition; Body Weight; Neurobehavioral Manifestations; Overweight; Obesity; Perceptual Disorders; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Obesity, Morbid; Agnosia; Physiological Effects of Drugs; Central Nervous System Depressants; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Narcotics; Anesthetics; Analgesics, Opioid
• Other Study ID Numbers: 31235/1.12.2022

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No