Opioid-free anesthesia in oncologic surgery: the rules of the game

BACKGROUND: Opioids are frequently used in the postoperative period due to their analgesic properties. While these drugs reduce nociceptive somatic, visceral, and neuropathic pain, they may also lead to undesirable effects such as respiratory depression, urinary retention, nausea and vomiting, constipation, itching, opioid-induced hyperalgesia, tolerance, addiction, and immune system disorders. Anesthesiologists are in the critical position of finding balance between using opioids when they are necessary and implementing opioid-sparing strategies to avoid the known harmful effects. This article aims to give an overview of opioid-free anesthesia. MAIN BODY: This paper presents an overview of opioid-free anesthesia and opioid-sparing anesthetic techniques. Pharmacological and non-pharmacological strategies are discussed, highlighting the possible advantages and drawbacks of each approach. CONCLUSIONS: Choosing the best anesthetic protocol for a patient undergoing cancer surgery is not an easy task and the available literature provides no definitive answers. In our opinion, opioid-sparing strategies should always be implemented in routine practice and opioid-free anesthesia should be considered whenever possible. Non-pharmacological strategies such as patient education, while generally underrepresented in scientific literature, may warrant consideration in clinical practice.