Feasibility and effectiveness of opioid-free anesthesia in cytoreductive surgery with or without heated intraperitoneal chemotherapy

Background Opioid-free anesthesia (OFA) provides analgesia minimizing opioids. OFA has not been evaluated in cytoreductive surgery (CRS) with or without heated intraperitoneal chemotherapy. We aim to evaluate OFA feasibility and effectiveness in CRS. Methods Retrospective cohort study of adult patients (84) undergoing CRS in a tertiary center from May 2020 until June 2021. Predefined protocols for either opioid-based anesthesia (OBA) or OFA were followed. Results OFA protocol patients (41) had better mean pain scores (1 +/- 0.8 vs. 2 +/- 1; p = 0.00) despite the avoidance of intravenous and epidural fentanyl intraoperatively (220 +/- 104 and 194 +/- 73 mu g, respectively, in OBA vs. 0; p = 0.00). Postoperative epidural levobupivacaine was also lower in the OFA group (575 +/- 192 vs. 706 +/- 346 mg; p = 0.034) despite the lack of epidural fentanyl without difference in duration (4.3 +/- 1.2 vs. 4 +/- 1.2 days; p = 0.22). Morphine consumption was very low (4.1 +/- 10 vs. 1.7 +/- 5 mg; p = 0.16). Intraoperative hypertensive events and postoperative nausea and vomiting (PONV) were higher for OBA (43) (30.2% vs. 7.3%; p = 0.01% and 69.8% vs. 34.1%; p = 0.001, respectively). Postoperative epidural fentanyl was independently associated with PONV (p = 0.004). There was no difference in total complications or length of stay. Conclusion OFA is feasible, safe, and offers optimal pain control while minimizing the use of opioids in CRS.