The effect of intraoperative lidocaine infusion on opioid consumption and pain after totally extraperitoneal laparoscopic inguinal hernioplasty: a randomized controlled trial

Background As a component of multimodal analgesia, the administration of systemic lidocaine is a well-known technique. We aimed to evaluate the efficacy of lidocaine infusion on postoperative pain-related outcomes in patients undergoing totally extraperitoneal (TEP) laparoscopies inguinal hernioplasty. Methods In this randomized controlled double-blind study, we recruited 64 patients to receive either lidocaine 2% (intravenous bolus 1.5 mg. kg .sup.- 1 followed by an infusion of 2 mg. kg.sup.- 1. h.sup.- 1), or an equal volume of normal saline. The infusion was initiated just before the induction of anesthesia and discontinued after tracheal extubation. The primary outcome of the study was postoperative morphine equivalent consumption up to 24 h after surgery. Secondary outcomes included postoperative pain scores, nausea/vomiting (PONV), sedation, quality of recovery (scores based on QoR-40 questionnaire), patient satisfaction, and the incidence of chronic pain. Results The median (IQR) cumulative postoperative morphine equivalent consumption in the first 24 h was 0 (0-1) mg in the lidocaine group and 4 [1-8] mg in the saline group (p < 0.001). Postoperative pain intensity at rest and during movement at various time points in the first 24 h were significantly lower in the lidocaine group compared with the saline group (p < 0.05). Fewer patients reported PONV in the lidocaine group than in the saline group (p < 0.05). Median QoR scores at 24 h after surgery were significantly better in the lidocaine group (194 (194-196) than saline group 184 (183-186) (p < 0.001). Patients receiving lidocaine were more satisfied with postoperative analgesia than those receiving saline (p = 0.02). No difference was detected in terms of postoperative sedation and chronic pain after surgery. Conclusions Intraoperative lidocaine infusion for laparoscopic TEP inguinal hernioplasty reduces opioid consumption, pain intensity, PONV and improves the quality of recovery and patient satisfaction. Trial registration ClinicalTrials.gov- NCT02601651. Date of registration: November 10, 2015. Keywords: Inguinal hernia, Laparoscopy, Lidocaine, Opioid analgesic, Postoperative pain