Analgesic efficacy of pre-emptive local wound infiltration plus laparoscopic-assisted transversus abdominis plane block versus wound infiltration in patients undergoing laparoscopic colorectal resection: results from a randomized, multicenter, single-blind, non-inferiority trial

Background: Transversus abdominis plane (TAP) block is considered a reliable locoregional technique for pain control after laparoscopic colorectal surgery. However, no clear benefit of TAP block over wound infiltration has been demonstrated by the current literature. This multicenter randomized clinical trial tested the non-inferiority of wound infiltration (WI) compared to WI plus laparoscopic-assisted TAP block (L-TAP). Methods: All patients with colorectal cancer and diverticular disease scheduled for laparoscopic resection at the Division of General and Hepatobiliary Surgery, University of Verona Hospital Trust, Verona, Italy and at the Colorectal Cancer Center, Kyungpook National University Medical Center, Kyungpook National University, Daegu, Korea, between April 2018 and March 2019 were considered for the trial. Patients were randomly allocated to either the WI group or the WI plus L-TAP group in a 1:1 allocation ratio. In total, 108 patients entered the study and 102 patients were analyzed; 50 patients received WI plus L-TAP and 52 patients received WI. The primary end point was the efficacy in pain control at 6 h measured according to Numeric Rating Scale (NRS). Secondary aims evaluated pain control at 12, 24, 48 and 72 h and other short-term results related to pain management. Results: Estimation of pain intensity at 6 h was comparable between the two groups (p = 0.16) with a mean (95% CI) difference in pain scores of 0.94 (− 0.13 to 2.02). No differences in pain scores were observed at other interval times or considering analgesic consumption, return of bowel function, postoperative complications and length of hospital stay. Conclusion: This study suggests that adding TAP block to WI does not affect pain control, amount of analgesics and other short-term outcomes. Trial registration: NCT03376048 (https://www.clinicaltrials.gov).