Comparison between opioid-based anaesthesia technique and opioid-free anaesthesia technique in patients undergoing laparotomy for gynaecological malignancy: A randomised controlled trial.

Abstract

Background and aims: To investigate whether opioid-free anaesthesia (OFA) or opioid-based anaesthesia (OBA) technique with ultrasound (US)-guided rectus sheath block (RSB) provides early recovery and less opioid-related side effects in patients undergoing laparotomy for gynaecological malignancy.

Methods: This was a double-blind randomised controlled trial. Fifty female patients of the American Society of Anesthesiologists (ASA) physical status I-II, aged 18-65 years, and scheduled to undergo elective gynaecological laparotomy under general anaesthesia were included. The patients were randomised into two groups. Both received US-guided RSB with 10 mL of local anaesthetic on each side. Group OBA (n = 25) received intravenous (IV) fentanyl 2 μg/kg at induction and 0.5 μg/kg as rescue analgesic. Group OFA (n = 25) received IV dexmedetomidine (0.5 μg/kg bolus over 10 min at induction, followed by 0.3 μg/kg/h infusion) and ketamine (0.25 mg/kg before incision, 0.15 mg/kg as rescue analgesic). The primary outcome was the time to attain post-anaesthesia care unit (PACU) discharge criteria. Time to eye-opening, time to extubation, time to shift to PACU, postoperative pain as visual analogue score (VAS), time to first rescue, total 24-h morphine consumption, and any postoperative nausea and vomiting till 24 h were also noted as secondary outcomes.

Results: The time to attain PACU discharge criteria was comparable between the groups; however, the time to extubation and time to shift to the PACU was higher in Group OFA (P = 0.043 and P = 0.046, respectively). Other secondary outcomes were comparable (P > 0.05).

Conclusion: OFA provides comparable postoperative analgesia and time to attain PACU discharge in adult patients undergoing open gynaecological oncological surgery under general anaesthesia.