Comparison of Balanced Anesthesia Protocols in Gastric Sleeve Surgery in Terms of Postoperative Opioid Consumption
Conditions: Obesity &Amp; Overweight, General Anesthetic, Ketamine
Sponsor: Balikesir University

16.05.2025 
NCT07135154 
 
Comparison of Balanced Anesthesia Protocols in Gastric Sleeve 
Surgery in Terms of Postoperative Opioid Consumption 
 
Postoperative Opioid Consumption in Gastric Sleeve Surgery  
POCiGSS 
 
Obesity, General anesthesia, Ketamine 
Ethics Committee Decision no: 2025/215 
 
 
 
In the study, a total of 205 sleeve gastrectomy surgery files performed between June 2024 
and March 2025 were scanned through the hospital data management system.  
Data obtained from age, gender, body mass index (BMI), additional diseases, anesthesia 
follow-up forms, and postoperative follow-up forms were collected.  
 
 
 
 

Inclusion criteria were ASA II-III scores, use of fentanyl and/or ketamine within the standard 
anesthesia protocol, and administration of opioids using patient-controlled analgesia. 
Exclusion criteria were incomplete data collection, deviation from the standard anesthesia 
protocol, and those who did not receive patient controlled analgesia management in 
postoperative pain management. The control group consisted of patients who underwent 
surgery using standard balanced anesthesia and fentanyl. The ketamine group consisted of 
patients who received ketamine infusion during surgery. 
Our clinic's standard anesthesia protocol for all sleeve gastrectomy surgeries is as follows: 
intravenous lidocaine (1.5 mg/kg ideal body weight), propofol (2.5 mg/kg lean body weight), 
fentanyl (1.0 µg/kg total body weight), and rocuronium (1 mg/kg ideal body weight) for rapid 
sequence endotracheal intubation. In cases where ketamine is administered after induction 
at the anesthesiologist's discretion, ketamine infusion (10 mg/mL diluted in a 50 cc syringe, 
500 mg vial) is administered at a rate of 0.2 mg/kg/hour based on lean body weight until 10 
minutes before the end of the surgery. Opioid medications are administered as needed. 
Neuromuscular blockade monitoring is performed, maintaining the point-of-four (TOF) ratio 
between 0 and 1. General anesthesia is maintained with sevoflurane in a low-flow oxygen and 
air mixture, guided by a bispectral index score between 40 and 60. Mechanical ventilation is 
administered to maintain normocapnia (end-tidal CO2: 35–40 mmHg). All patients receive 8 
mg of IV dexamethasone according to surgical clinic protocol. Sugammadex (2 mg/kg) is 
administered for reversal of muscle relaxation. All patients are monitored postoperatively in 
the postanesthesia care unit and ward. Sedation is assessed using the Observer's Assessment 
of Alertness/Sedation Scale (OASS). Patients are instructed preoperatively on the use and 
values of the Numerical Rating Scale (NRS). Opioids are administered IV using a 
patientcontrolled analgesia device. Postoperative pain is assessed intermittently using the 
NRS. All patients receive 1 g of IV paracetamol every 8 hours and 50 mg of IV dexketoprofen 
every 12 hours for 24 hours from the start of surgery. The primary outcome measured in the 
study was 24-hour opioid consumption via a patientcontrolled analgesia device, while 
secondary outcomes were systolic blood pressure (SBP), diastolic blood pressure (DBP), mean 
blood pressure (MBP), heart rate (HR), peripheral oxygen saturation (SpO2) values measured 
during surgery and in the recovery room, as well as OASS and NRS values. 
Statistical analyses were performed using the NCSS (Number Cruncher Statistical System) 
2007 Statistical Software (Utah, USA) package program. In the sample size analysis, a power 
value of 0.8 was used, and the minimum sample size for each group was found to be 47 
patients. In the analysis of data, descriptive statistical methods (mean, standard deviation, 
median, interquartile range) were used, as well as the Shapiro–Wilk normality test to examine 
the distribution of variables. The independent t-test was used for pairwise comparisons of 
normally distributed variables, the Mann-Whitney U test for pairwise comparisons of 
nonnormally distributed variables, and the chi-square test for comparisons of qualitative data. 
Significance was assessed at p<0.05.