A randomized, double-blinded, placebo-controlled trial of the effects of infusing local analgesia on post-operative pain during laparoscopic inguinal hernia repair.

Abstract

While it is widely accepted that laparoscopic total extraperitoneal (TEP) inguinal herniorrhaphy has decreased post-operative pain, there are conflicting data as to whether instillation of local anesthetic into the preperitoneal space improves post-operative pain in these patients. We designed a prospective study to evaluate this. Secondary outcomes include time spent in the PACU, need for narcotic pain medication, and total amount of narcotics required postoperatively. Prospective, randomized, double-blind, placebo-controlled study which enrolled 70 patients with unilateral non-recurrent inguinal hernia from 09/2013 to 03/2019 and included immediate and 2-week post-operative follow-up. All patients received unilateral laparoscopic TEP inguinal hernia repair with control patients receiving 10ml of 0.9% saline instilled into preperitoneal space while treatment group received 10-ml 0.5% bupivacaine without epinephrine. A total of 70 patients [67 (96%) men and 3 women; mean age (SD), 57years (13.8)] were enrolled, 35 randomized into each group. Demographics between the two groups were similar. No differences were found in post-operative pain between the control and test groups at 1h [mean (SD) of 3.15(2.5) vs 3.21(2.9); P = 0.92], 2h [3.39 (1.55) vs 2.74 (1.85) P = 0.18], or 1day [4.79 (2.19) vs 4.39 (2.37); P = 0.13] postoperatively. Likewise, no significant differences were observed in usage of narcotic pain medication postoperatively, as 17 control patients (50%) and 16 (46%) study patients required narcotics within 2h of surgery (P = 0.72). Instilling local anesthetic into the preperitoneal space during laparoscopic TEP inguinal hernia repair did not result in statistically significant difference in post-operative pain (Rade et al. in NESS Annual Meeting, 2021). Trial registry ClinicalTrials.gov Identifier: NCT02055053.