Intravenous Lidocaine in Liver Surgery ‒ A Randomized Double-Blind Trial

Managing postoperative pain is a complex challenge in liver surgery. Perioperative intravenous (IV) lidocaine can reduce postoperative pain, opioid use, bowel recovery time and the length of stay, in various types of surgery. Lidocaine is eliminated via hepatic metabolism, and IV lidocaine is rarely evaluated in liver surgery. This study aimed to evaluate the postoperative analgesic efficacy and safety of IV lidocaine administration in patients undergoing minor liver surgery.

Patients planned for minor liver surgery were randomized 1:1 to receive either perioperative IV lidocaine, administered as a 1.5 mg/kg bolus followed by a continuous infusion of 1.5 mg/kg/h until 1 hour after surgery, or placebo. All patients received postoperative opioid analgesia via a patient-controlled analgesia device. The primary outcome was postoperative opioid consumption during the first 24 hours after surgery. Secondary outcomes included postoperative pain scores, quality of recovery, adverse events, length of stay, and plasma lidocaine concentrations.

In total, 124 subjects were included. Postoperative opioid consumption during the first 24 hours after surgery was 83 (50 - 129) mg oral morphine equivalents (OME) in the lidocaine group, and 97 (60 - 135) mg OME in the placebo group, p=0.429. Patients in the lidocaine group experienced lower pain scores at early postoperative time points, but not from postoperative day 1 onward. The Quality of recovery-40 score did not differ, and adverse events were similar between groups. In two cases, plasma concentrations of lidocaine were transiently above 5 µg/ml after bolus administration, without clinical signs of toxicity. All plasma concentrations after resection and at end of infusion were safely below toxic levels.

Perioperative intravenous lidocaine did not reduce postoperative opioid consumption after minor liver surgery but conferred transient early analgesic benefits and was found to be safe.