Opioid-free versus opioid-based anesthesia in major spine surgery: a prospective, randomized, controlled clinical trial

BACKGROUND: Major spine surgery is associated with severe postoperative pain and increased opioid consumption. Opioid-free anesthesia (OFA) is thought to provide adequate intraoperative analgesia with reduced postoperative opioid consumption. The aim of this study is to compare the impact of intraoperative OFA approach to the conventional opioid-based anesthesia (OBA) on postoperative pain, opioid consumption, and related side effects in patients undergoing multilevel spinal fusion surgery.METHODS: Forty-eight patients undergoing elective major spine surgery were randomly allocated to either receive intraoperative dexmedetomidine and lidocaine (OFA group) or fentanyl during induction and intraoperative remifentanil (OBA group). All patients received intraoperative sevoflurane, propofol, rocuronium, ketamine, dexamethasone, ondansetron and postoperative paracetamol and patient-controlled analgesia device set to deliver intravenous morphine for 48 hours after surgery. Postoperative pain was measured using numerical rating scale. Opioid side effects were documented, when present.RESULTS: OFA group required less morphine in the first 24 hours post-surgery (17.28±12.25 mg versus 27.96±19.75 mg, P<0.05). The incidence of postoperative nausea and vomiting (PONV) was significantly lower in the OFA group. More patients in the OFA group required antihypertensive medications compared to patients in the OBA group (P<0.05). In the post anesthesia care unit, OFA patients had a significantly longer stay than OBA patients (114.1±49.33 min versus 89.96±30.71 min, P<0.05).CONCLUSIONS: OFA can be an alternative to OBA in patients undergoing multilevel spine fusion surgery. OFA reduces opioids consumption in the first 24 hours and PONV.