Opioid-free anesthesia using a combination of ketamine and dexmedetomidine in patients undergoing laparoscopic cholecystectomy: a randomized controlled trial

Background: Opioids administered as bolus doses or continuous infusions are widely used by anesthesiologists worldwide for major and day care surgeries. Opioid-free anesthesia is a multimodal anesthesia and analgesia technique that does not use opioid drugs, thereby benefitting patients from opioid-related adverse effects. In this study, we compared the postoperative analgesic requirements of patients scheduled for elective laparoscopic cholecystectomy under opioid-free and opioid-based anesthesia.Methods: This study included 88 patients aged 18–60 years with American Society of Anesthesiologists physical status 1 and 2 who underwent elective laparoscopic cholecystectomy. Participants were randomly divided into two groups with forty-four participants in each group. The opioid-free anesthesia group was administered an intravenous bolus of ketamine and dexmedetomidine, whereas the opioid-based group was administered fentanyl with conventional general anesthesia. The primary outcome was to compare the total amount of fentanyl consumed by both groups during the 6 h postoperative period following extubation. Episodes of postoperative nausea and vomiting (PONV) and vital signs were noted throughout the postoperative period to analyze the secondary outcomes.Results: Both the groups had similar demographic characteristics. The opioid-free group required less postoperative analgesia within the first 2 h (61.4 ± 17.4 vs. 79.0 ± 19.4 of fentanyl, P < 0.001), which was statistically significant. However, fentanyl consumption was comparable between the groups at the sixth postoperative hour (opioid-free group 152 ± 28.2 vs. opioid group 164 ± 33.4, P = 0.061). Compared with 4.5% of the participants in the opioid-free group, 34% of those in the opioid-based group developed moderate PONV.Conclusions: The opioid-free anesthesia technique in patients undergoing laparoscopic cholecystectomy reduced the requirement of analgesia in the first two hours of the postoperative period and was associated with decreased PONV.