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 for major and daycare surgeries. Opioid-free anesthesia is multimodal anesthesia and anal-gesia that does not use opioids, benefiting patients from opioid-related adverse effects. We compared the postoperative analgesic requirements of patients scheduled for elective lapa-roscopic cholecystectomy under opioid-free and opioid-based anesthesia. Methods: Study included 88 patients aged 18-60 years with American Society of Anesthe-siologists physical status 1 and 2 who underwent elective laparoscopic cholecystectomy. Participants were randomly divided into two groups with 44 in each. The opioid-free group was administered an intravenous bolus of ketamine and dexmedetomidine, whereas fentan-yl was used in opioid group. Primary outcome was to compare the total amount of fentanyl consumed by both groups during 6 h postoperative period. Episodes of postoperative nau-sea and vomiting (PONV) and vital signs were noted throughout the postoperative period to analyze the secondary outcomes. Results: Both groups had similar demographic characteristics. The opioid-free group re-quired lesser 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 6 h (152 +/- 28.2 vs. 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: Opioid-free anesthesia in patients undergoing laparoscopic cholecystectomy reduced the requirement of analgesia in first two-hour postoperative period and was associ-ated with decreased PONV.