Randomized, Double-Blind Study of the Effect of Intraoperative Intravenous Lidocaine on the Opioid Consumption and Criteria for Hospital Discharge After Bariatric Surgery

Background and Objectives Surgical trauma, pain and opioids can cause nausea, vomiting, ileus and increased length of hospital stay. The primary objective of the study was to evaluate the time to recovery of gastrointestinal function and the time to meet hospital discharge criteria after laparoscopic bariatric surgery with intraoperative intravenous lidocaine administration. Secondary objectives were to evaluate morphine consumption during the first 24 h and the side effects of opioids. Methods Fifty-eight patients aged 18 to 60 years who underwent bariatric surgery were allocated into two groups. Group 1 patients received intravenous lidocaine (1.5 mg/kg) 5 min before induction of anaesthesia, followed by infusion (2 mg/kg/h) until the end of surgery. Group 2 patients were given 0.9% saline solution (placebo) and infusion of 0.9% saline solution during surgery, in same volume as group 1. Anaesthesia was performed with fentanyl (5 mu g/kg), propofol (2 mg/kg), rocuronium (0.6 mg/kg) and sevoflurane. Postoperative patient-controlled analgesia was with morphine. There were two groups that were evaluated: time to recovery of gastrointestinal function and time to meet discharge criteria. Results There was no significant difference between groups regarding the time to first flatus, time to meet discharge criteria and occurrence of side effects. Consumption of intraoperative sevoflurane and morphine over 24 h was significantly lower in the lidocaine group. Side effects observed were nausea and vomiting, with no difference between groups. Conclusions Perioperative intravenous lidocaine is feasible and easily accessible when administered at appropriate doses. Lidocaine reduces morphine consumption.