Postoperative and Opioid Free Anesthesia

Overview

Since the 1960's, intraoperative administration of opioids is considered a keystone of anesthesia as well as hypnotics and muscle relaxants. Synthetic opioids were introduced to achieve hemodynamic stability during anesthesia. They allow an inhibition of the sympathetic system without cardiovascular collapse and histamine release. Since then, anesthesia has changed from inhalation to multimodal anesthesia with lower doses of hypnotic. In 2017, the intraoperative objectives of hypnosis, hemodynamic stability, immobility and anticipation of postoperative analgesia can be achieved without opioids. Moreover, opioid administration consequences are neither scarce nor benign for the patient. Perioperative opioids are associated with nausea and vomiting, sedation, ileus, confusion/delirium, respiratory depression, increased postoperative pain and morphine consumption, immunodepression, hyperalgesia and chronic postoperative pain. Among these complications, hypoxemia, ileus and confusion/delirium are the most frequent. Efficacious multimodal analgesia and anesthesia are the basis of successful fast-track surgery. These multidrug regimens aim at decreasing postoperative pain, intra- and postoperative opioid requirements, and subsequently, opioid-related adverse effects and to fasten recovery. Opioid-free postoperative analgesia has been recommended for more than 10 years. Opioid-free anesthesia (OFA) is based on the idea that hemodynamic stability can be achieved without opioids during anesthesia. OFA is multimodal anesthesia associating hypnotics, N-methyl-D-aspartate (NMDA) antagonists, local anesthetics, anti-inflammatory drugs and alpha-2 agonists (Dexmedetomidine). Proofs of the effect of OFA on reducing opioid-related adverse effects after major or intermediate non-cardiac surgery are still scarce. We hypothesized that the reduced opioid consumption during and after surgery allowed by OFA compared with standard of care will be associated with a reduction of postoperative opioid-related adverse events.