Effect of intravenous lidocaine on pain after head and neck cancer surgery (ELICO trial) A randomised controlled trial

BACKGROUND Treatment of postoperative pain after ear, nose and throat (ENT) cancer surgery is mainly morphine administration. Additional systemic lidocaine has shown promising results in some surgical procedures. OBJECTIVE The main objective was to evaluate morphine consumption in the first 48 postoperative hours after intra-operative lidocaine infusion during major ENT cancer surgery. DESIGN A randomised, double-blind, placebo-controlled trial. SETTING Bicentric study including a university hospital and a major cancer centre, conducted from December 2016 to December 2019. PATIENTS A total of 144 patients undergoing major ENT cancer surgery were included. INTERVENTION The patients were randomly assigned to receive intravenous lidocaine or placebo during surgery and in the recovery room. MAIN OUTCOME MEASURES Endpoints were postoperative morphine consumption in the first 24 and 48 h postoperatively, intra-operative remifentanil consumption, adverse events occurrence and assessment 3 to 6 months after surgery with the McGill pain questionnaire. RESULTS A total of 118 patients were included (lidocaine n = 57; placebo n = 61, 26 patients were excluded). There was no significant difference in morphine consumption during the first 48 postoperative hours in the lidocaine group compared with the placebo group with a median [IQR] of 0.60 [0.30 to 1.03] mg kg(-1) vs. 0.57 [0.37 to 0.96] mg kg(-1), total dose 44 [21 to 73.3] mg vs. 38 [23.3 to 56.5] mg, P = 0.92. There was no significant difference between the two groups in any of the other endpoints, including at follow up 3 to 6 months after surgery. CONCLUSION Intravenous lidocaine in ENT cancer surgery did not show any additional analgesic or morphine-sparing effect 48 h after surgery. Three to six months after surgery, there was no significant difference in pain scores or consumption of analgesics. Patients treated pre-operatively with opioids were not evaluated in the study.