Opioid Free vs Opioid Based Anesthesia for Laparoscopic Sleeve Gastrectomy

Study Overview
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Brief Summary
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Opioid free anesthesia is an anesthetic technique, in which administration of multimodal analgesia and sympathicolytics provides hemodynamic stability without use of opioids. Such management may be beneficial to the obese patients undergoing laparoscopic sleeve gastrectomy. Our study aims to compare opioid free anesthesia in such patients with standard, short-acting opioid based.

Detailed Description
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The study has been approved by Bioethical Committee of Medical University of Warsaw. Informed written consent will be obtained from all patients. Sample size of 60 patients has been calculated based on the Altman normogram to obtain 30% reduction of postoperative opioid consumption with significance and power of 90%. Consenting patients scheduled for laparoscopic sleeve gastrectomy will be randomly assigned to the computer generated list to receive opioid free or standard opioid based anesthesia. Opioid free protocol includes administration of dexmedetomidine, lidocaine, ketamine, magnesium sulphate whereas standard group will receive remifentanil TCI Minto Model. After the end of operation all of the patient will receive oxycodone and additional doses via PCA system for postoperative analgesia.

Official Title
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Opioid Free vs Opioid Based Anesthesia for Laparoscopic Sleeve Gastrectomy: Clinical, Randomised Study

Conditions
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Obesity, Postoperative Pain, Postoperative Nausea, Postoperative Vomiting, Opioid Use

Intervention / Treatment
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* Drug: Dexmedetomidine Hydrochloride [Dexdor]
* Drug: Remifentanil [Ultiva]
* Drug: Ketamine [Ketalar]
* Drug: Lidocaine [Xylocaine 2%]
* Drug: Magnesium Sulphate [Inj. Magnesii Sulfurici Polpharma]
* Drug: Fentanyl [Fentanyl WZF]


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Sleeve gastrectomy in patients with BMI > 40 or >35 with comorbidities Written informed consent Exclusion Criteria: Patient's refusal Known allergies to study medication Inability to comprehend or participate In pain scoring scale Inability to use intravenous patient controlled analgesia Changes of operation extent during procedure Revisional operations

Ages Eligible for Study
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Minimum Age: 18 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Opioid liberal group<br> | Drug: Remifentanil [Ultiva]<br>* Remifentanil TCI Minto Model will be used during induction in dosis 6 ng/ml and intraoperatively appropriately to maintain hemodynamical stability.<br>|
| Experimental: Opioid free group<br> | Drug: Dexmedetomidine Hydrochloride [Dexdor]<br>* Initial dosis of dexmedetomidine 1 mcg/kg IBW iv will be administered within 10 minutes before general anesthesia induction. Following intubation infusion of 1 mcg/kg IBW / h will be initiated and continued until the end of operation.<br>Drug: Ketamine [Ketalar]<br>* Ketamine 0,5mg/kg IBW iv will be administered during induction of general anesthesia.<br>Drug: Lidocaine [Xylocaine 2%]<br>* Initial dosis of lidocaine 1,5 mg/kg IBW iv will be administered within 10 minutes before general anesthesia induction. Following intubation infusion of 3 mg/kg IBW / h will be initiated and continued until the end of operation.<br>Drug: Magnesium Sulphate [Inj. Magnesii Sulfurici Polpharma]<br>* Magnesium Sulphate will be administered in dosis 50 mg/kg IBW iv intraoperatively.<br>Drug: Fentanyl [Fentanyl WZF]<br>* Rescue dosis of 100 mcg iv will be administered if hypertension > 140/90 mmHg or tachycardia > 120min occurs. If necessary rescue dosis may be repeated.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total postoperative oxycodone consumption | PCA (Patient's controlled analgesia) iv pump, oxycodone will be administered on patient's demand by 2mg boli, with lock out time 10 minutes | Day 0 | 
| Postoperative pain score in NRS scale | NRS range from 0 for no pain to 10 for worst pain imaginable | Day 0, assessed 1 hour after operation | 
| Postoperative pain score in NRS scale | NRS range from 0 for no pain to 10 for worst pain imaginable | Day 0, assessed 6 hours after operation | 
| Postoperative pain score in NRS scale | NRS range from 0 for no pain to 10 for worst pain imaginable | Day 0, assessed 12 hours after operation | 
| Postoperative pain score in NRS scale | NRS range from 0 for no pain to 10 for worst pain imaginable | Day 1 assessed 24 hours after operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative sedation score | 1-6 Ramsay sedation score; 1 - agitated or restless 6 - unresponsive | Day 0, assessed 1,6,12 and 24 hours after operation | 
| Postoperative nausea and vomiting | Simplified PONV impact scale 0-6 0 - no nausea nor vomiting 6 - >3 episodes of vomiting and nausea all of the time | Day 0, assessed 1,6,12 and 24 hours after operation | 
| Rescue fentanyl administration dosis | In opioid free group, rescue fentanyl dosis will be administered if hypertension > 140/90 mmHg or tachycardia > 120/min occurs | intraoperative | 
| Highest BP | Highest BP during operation | intraoperative | 
| Lowest BP | Lowest BP during operation | intraoperative | 
| Highest HR | Highest HR during operation | intraoperative | 
| Lowest HR | Lowest HR during operation | intraoperative | 
| Total ephedrine dosis | Ephedrine is a vasopressor used in case of hypotension to maintain mean arterial pressure > 65 mmHg or to increase blood pressure to check surgical hemostasis | intraoperative | 
| Postoperative desaturation | SpO2 < 94% | Day 0, assessed 1,6,12 and 24 hours after operation | 
| Patient's comfort assessed in QoR-40 formulary | QoR-40 scale is used to measure the quality of recovery after surgery and anesthesia, it is a 40 item questionnaire that provides a score across five dimensions: patient support, comfort, emotions, physical independence, and pain. Formulary will assess first 24 hours following the operation and will be filled by the patient 7 days after operation | 7 days postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Opioid free anesthesia, Laparoscopic sleeve gastrectomy