Opioid-free anesthesia vs Opioid-based anesthesia

Background Bariatric surgery is considered the most effective treatment for morbid obesity, but perioperative pain control and the prevention of postoperative nausea and vomiting (PONV) remain major clinical challenges. Traditional opioid-based anesthesia (OBA) is effective for antinociception but associated with adverse effects, prompting increasing interest in opioid-free anesthesia (OFA). Methods In this prospective, randomized study, 60 patients undergoing laparoscopic bariatric surgery were allocated to receive either OBA (desflurane + remifentanil, with postoperative multimodal analgesia including morphine) or OFA (desflurane + dexmedetomidine, lidocaine, ketamine, and opioid-free multimodal postoperative analgesia). Primary outcomes included postoperative pain (Numerical Rating Scale, NRS) and need for rescue analgesia. Secondary outcomes were intraoperative nociception (NOL index), incidence of PONV, and patient satisfaction. Results The OFA group showed significantly lower pain scores at PACU discharge (p = 0.004), within the first 24 hours (p = 0.035), and at hospital discharge (p = 0.023), as well as a reduced need for rescue analgesia (p = 0.002). NOL monitoring suggested improved intraoperative nociception control with OFA. No significant differences were found in PONV incidence between groups. Patient satisfaction was high in both groups, with a non-significant trend favoring OFA. No major perioperative complications were observed. Conclusions Opioid-free anesthesia demonstrated superiority over opioid-based techniques in reducing postoperative pain and rescue analgesia requirements in bariatric surgery, without increasing adverse events. These findings support OFA as a safe and effective strategy, warranting larger multicenter trials to validate its clinical benefits and long-term impact. Trial registration: NCT Number: NCT07337135. Registered on 13th January 2026. Retrospectively registered.