Hemodynamics Stability During Opioid Free Anesthesia for Patients with Obesity

A Comparison of Opioid-Free Anesthesia (OFA) and Standard Fentanyl-based General Anesthesia in Patients with Morbid Obesity Undergoing Laparoscopic Bariatric Surgery

The study evaluated the impact of Opioid-Free Anesthesia (OFA) and Fentanyl Anesthesia (FNT) on the hemodynamics of the circulatory system (HR, esCCO, esCCI, esSVI, BP: SYS, DIA, MEAN) in obese patients with a BMI > 40 undregoing laparoscopic bariatric surgery. Patients in the OFA group were anesthetized as follows: before induction: ketamine 0.15 mg/kg (corrected body weight), lidocaine 1-1.5 mg/kg (corrected body weight) slow infusion, magnesium sulfate 30-50 mg/kg (corrected body weight), dexamethasone 8 mg, paracetamol 2.0g. Maintenance: continuous infusion of ketamine 0.125-0.25 mg/kg/h (corrected body weight), lidocaine 1.5-3 mg/kg/h (corrected body weight), magnesium sulfate 10 mg/kg/min (corrected body weight), and rocuronium bromide 1.25 µg/kg/min (corrected body weight) were used. Patients in the FNT group were anesthetized as follows: before induction: fentanyl 1.5-3 µg/kg (corrected body weight) iv, preoxygenation with 100% oxygen for 3 minutes, propofol 2.5 mg/kg (actual body weight) and following confirmation of mask ventilation, rocuronium bromide 0.6 mg/kg (actual body weight) bolus. After achieving full neuromuscular blockade, the patient was intubated and connected to the anesthesia machine and ventilated with 1-1.5 MAC desflurane.

Study Overview

• Status: Completed
• Conditions: Obesity; General Anesthesia; Opioid Free Anaesthesia
• Intervention / Treatment: Drug: Opioid Free Anaesthesia; Drug: Opioid based Anesthesia

Detailed Description

Adult patients (over 18 years old) with a BMI ≥ 40, ASA ≤ II, qualified for elective bariatric surgery under general anesthesia with endotracheal intubation, who provided informed, voluntary consent to participate in the study, were included. Patients with BMI < 40, ASA III and above, heart failure, arrhythmias (especially bradyarrhythmia), hypovolemia, shock, unstable coronary artery disease, autonomic neuropathy with orthostatic hypotension, with a history of allergic reactions, pregnancy, indications for urgent surgical intervention, or those who did not consent to participate in the study, were excluded. Patients' weight, height, and BMI were measured. All obtained data were anonymized.

After transporting the patient to the operating room, the envelope was opened, and the patient was assigned to either the OFA or FNT anesthesia group.

Patients in the OFA group were anesthetized as follows: before induction: ketamine 0.15 mg/kg (corrected body weight), lidocaine 1-1.5 mg/kg (corrected body weight) slow infusion, magnesium sulfate 30-50 mg/kg (corrected body weight), dexamethasone 8 mg, paracetamol 2.0g. Induction: after three minutes of preoxygenation with 100% oxygen, propofol 2.5 mg/kg (actual body weight) was administered. Following confirmation of mask ventilation, rocuronium bromide 0.6 mg/kg (actual body weight) was given. Bag-mask ventilation with 100% oxygen continued for 3 minutes. After achieving full neuromuscular blockade, confirmed by the loss of all four responses using a peripheral nerve stimulator, the patient was intubated and connected to the anesthesia machine and ventilated with 1-1.5 MAC sevoflurane. Maintenance: ketamine 0.125-0.25 mg/kg/h (corrected body weight), lidocaine 1.5-3 mg/kg/h (corrected body weight), magnesium sulfate 10 mg/kg/min (corrected body weight), and rocuronium bromide 1.25 µg/kg/min (corrected body weight) were used. After surgery, neuromuscular blockade was reversed with sugammadex at 2-4 mg/kg (corrected body weight). The patients were also administered ephedrine in case of hypotension, atropine for bradycardia, and beta-blockers for tachycardia and hypertension.

Patients in the FNT group were anesthetized as follows: before induction: fentanyl 1.5-3 µg/kg (corrected body weight) iv, preoxygenation with 100% oxygen for 3 minutes, propofol 2.5 mg/kg (actual body weight) and following confirmation of mask ventilation, rocuronium bromide 0.6 mg/kg (actual body weight) bolus. Bag-mask ventilation with 100% oxygen and 2% inhaled sevoflurane continued for 3 minutes. After achieving full neuromuscular blockade, the patient was intubated and connected to the anesthesia machine and ventilated with 1-1.5 MAC desflurane. Maintenance dose for fentanyl was 0.003-0.006 µg/kg/min (corrected body weight) and rocuronium bromide 1.25 µg/kg/min (corrected body weight) were used. After surgery, neuromuscular blockade was reversed with sugammadex at 2-4 mg/kg (corrected body weight).

During induction, patients were positioned supine with the head and torso elevated at a 25-degree angle on a positioning pad. Anesthetic monitoring included HR, NIPC-SYS, NIPC-MEAN, NIPC-DIA, SpO2, esCCO, esCCI, and esSVI using the Vismo monitor and EtCO2.

Hemodynamic parameters (esCCO, esCCI, esSVI, NIPC-SYS, NIPC-MEAN, NIPC-DIA, HR) were measured before induction (T0) and then at 10-minute intervals after intubation and connection to the anesthesia machine (from T1 to T10).

The objective of the study is to compare the impact of OFA on hemodynamic parameters measured by non-invasive technique: esCCO, esCCI, esSVI, NIPC-SYS, NIPC-MEAN, NIPC-DIA, HR, in obese patients with BMI > 40, with those obtained during the commonly used FNT anesthesia.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Poland
  • Lodz, Poland, 90-153
    • Medical University of Lodz

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

- obese patients with a BMI > 40 kg/m2 undergoing elective laparoscopic bariatric surgery

Exclusion Criteria:

• lack of consent
• emergency operation

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: opioid free anesthesia; patients received opioid free anesthesia	Drug: Opioid Free Anaesthesia; patients received opioid free anesthesia
Active Comparator: opioid based anesthesia; patients received opioid based anesthesia	Drug: Opioid based Anesthesia; patients received opioid based anesthesia

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
hemodynamic stability, cardiac output	Hemodynamic parameters (esCCO - cardiac output l/min) were measured using Visimo monitor.	before induction (T0) and then at 10-minute intervals after intubation and connection to the anesthesia machine (from T1 to T10)
hemodynamic stability esCCI - cardiac index	Cardiac index esCCI - l/m2 was measured using Visimo monitor.	before induction (T0) and then at 10-minute intervals after intubation and connection to the anesthesia machine (from T1 to T10)
hemodynamic stability esSVI	Stroke voulme esSVI - l were measured using Visimo monitor.	before induction (T0) and then at 10-minute intervals after intubation and connection to the anesthesia machine (from T1 to T10)
hemodynamic stability: arterial pressure NIPC-SYS, NIPC-MEAN, NIPC-DIA	Arterial pressure NIPC-SYS, NIPC-MEAN, NIPC-DIA (mmHg) were measured using Visimo monitor.	before induction (T0) and then at 10-minute intervals after intubation and connection to the anesthesia machine (from T1 to T10)
hemodynamic stability HR - heart rate	HR were measured using Visimo monitor.	before induction (T0) and then at 10-minute intervals after intubation and connection to the anesthesia machine (from T1 to T10)

Collaborators and Investigators

• Sponsor: Medical University of Lodz

Study record dates

Study Major Dates

• Study Start (Actual): January 2, 2022
• Primary Completion (Actual): January 2, 2023
• Study Completion (Actual): June 2, 2023

Study Registration Dates

• First Submitted: November 25, 2024
• First Submitted That Met QC Criteria: December 3, 2024
• First Posted (Estimated): December 4, 2024

Study Record Updates

• Last Update Posted (Estimated): December 4, 2024
• Last Update Submitted That Met QC Criteria: December 3, 2024
• Last Verified: November 1, 2024

More Information

Terms related to this study

• Keywords: obesity; general anesthesia; fentanyl; hemodynamics; Opioid-Free Anesthesia
• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Overweight; Obesity; Physiological Effects of Drugs; Peripheral Nervous System Agents; Central Nervous System Depressants; Sensory System Agents; Analgesics; Narcotics; Analgesics, Opioid; Anesthetics
• Other Study ID Numbers: RNN/60/16/KE

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No