Abstract
Opioid-free anesthesia (OFA) and opioid-sparing anesthesia (OSA) have emerged from two converging developments in perioperative medicine: first, the need to reduce opioid-related adverse drug events such as postoperative nausea and vomiting (PONV), respiratory depression, ileus, sedation, and possibly persistent postoperative use; and second, the maturation of enhanced recovery pathways built around multimodal, function-oriented analgesia. In contemporary evidence, however, strict elimination of intraoperative opioids has not shown universal superiority over well-conducted opioid-based anesthesia (OBA) for postoperative pain control or 24-hour opioid consumption. The most reproducible benefit of OFA is lower PONV in selected settings, whereas the most important safety signal is regimen-dependent bradycardia and hemodynamic instability, especially in dexmedetomidine-heavy protocols. By contrast, broader OSA strategies, particularly when built on acetaminophen, NSAIDs, regional anesthesia, judicious total intravenous anesthesia (TIVA), and selected adjuvants such as ketamine or lidocaine, are aligned with ERAS and other major perioperative guidance and have the strongest overall clinical support.
This narrative review examines definitions, mechanisms, pharmacology, protocols, clinical outcomes, limitations, and practical applications of OFA and OSA in modern perioperative care.
Conclusion: contemporary perioperative practice is better supported by individualized opioid stewardship and multimodal opioid-sparing care than by a dogmatic “zero-opioid” rule. OFA remains a reasonable option in selected phenotypes and procedures, but current evidence does not justify its routine use as a default replacement for all opioid-inclusive techniques.