Bolus administration of intravenous lidocaine reduces pain after an elective caesarean section: Findings from a randomised, double-blind, placebo-controlled trial.

We conducted a randomised double-blind, placebo-controlled trial to assess whether a bolus dose of lidocaine during the induction of general anaesthesia would reduce postoperative pain over 24 h. Level of satisfaction with pain control at 48 h after surgery and Apgar score were also examined. A total of 100 women aged 20-35 years, who were candidates for elective caesarean section (CS) were randomised to receive either 1.5 mg/kg lidocaine or placebo during the induction of general anaesthesia. Results showed that lidocaine decreased pain intensity over 24 h after surgery (p < .001), and decreased postoperative morphine consumption from median (range) of 3.79 (0-9) mg in the placebo group to 0 (0-12) mg and in the lidocaine group (p <.001). Lidocaine was not associated with postoperative nausea and vomiting or any side effects in women and newborn babies. We conclude that a small bolus dose of lidocaine attenuates postoperative pain, thus reducing the requirement for opioid consumption in the postoperative period. Impact statement • With its anti-inflammatory, anti-hyperalgesic and analgesic properties, intravenous perioperative lidocaine infusion (IVLI) has been used for optimal postoperative care in different surgeries. Limited evidence suggests that IVLI may be a useful adjuvant during general anaesthesia. There is a report of a positive effect on several outcomes after surgery including postoperative pain over 24 h after laparoscopic abdominal surgery or open abdominal surgery. However, there was a paucity of information regarding the efficacy of a bolus dose of lidocaine in patients undergoing caesarean section (CS). In this randomized, placebo-controlled trial the use of a bolus dose of 1.5 mg/kg lidocaine 2%, compared with placebo, during the induction of general anaesthesia for elective CS resulted in a significant decrease in postoperative pain score as well as decreased postoperative morphine consumption over 24 h. Lidocaine use was not associated with any side effect in participants and newborns. • This study provides the first evidence that a bolus dose of lidocaine may be a safe and simple alternative therapeutic intervention for enhanced postoperative recovery in terms of pain and postoperative opioid consumption. Future studies are needed to examine pain reducing effect of perioperative bolus dose of lidocaine after CS under spinal or epidural anesthesia.