Opioid-Free Versus Opioid-Based Anaesthesia for Postoperative Pain and Recovery

Abstract

Background: Opioid-free anaesthesia has gained attention as a strategy to prevent opioid-related harm, yet its advantages over contemporary opioid-sparing or opioid-inclusive multimodal anaesthesia remain contested. Complete intraoperative opioid avoidance does not necessarily imply opioid-free perioperative care, and postoperative pain, recovery, adverse effects and longer-term opioid exposure are distinct outcomes. Objective: This critical narrative review evaluates comparative evidence on postoperative analgesia and opioid consumption, patient-reported recovery, nausea and vomiting, physiological safety, and the interpretation of conflicting trials and meta-analyses. Methods: Peer-reviewed randomised trials, systematic reviews, methodological studies and relevant perioperative consensus publications were identified through structured searches of accessible scholarly sources covering 2000 to 12 August 2026. Evidence was examined according to the intervention comparator, surgical setting, co-interventions, outcome validity, clinical importance, risk of bias and generalisability. The synthesis is interpretive rather than a new quantitative meta-analysis. Synthesis: Opioid-free protocols can provide satisfactory postoperative analgesia, and some studies report reduced postoperative nausea and vomiting or improved early recovery scores. Neither lower pain intensity nor reduced postoperative opioid requirements, however, is a consistent advantage over well-designed opioid-sparing techniques. Differences in regional blockade, total intravenous versus volatile anaesthesia, antiemetic prophylaxis and non-opioid drug combinations complicate causal attribution. Benefits observed on recovery questionnaires are frequently smaller than accepted minimal clinically important differences or are accompanied by substantial heterogeneity. The multicentre POFA trial identified excess hypoxaemia and severe bradycardia with a dexmedetomidine-based opioid-free regimen, demonstrating that avoidance of opioids can exchange rather than abolish pharmacological risk. Evidence of prevention of persistent pain or long-term opioid use remains insufficient. Conclusions: Routine adoption of opioid-free anaesthesia as a universal superiority strategy is not supported. A patient- and procedure-specific approach that prioritises multimodal analgesia, effective regional techniques, appropriate antiemetic prophylaxis, measured opioid exposure and drug-specific safety offers a more defensible interpretation of the current evidence.