Do transversus abdominis plane (TAP) blocks improve pain after laparoscopic bilateral inguinal hernia repairs beyond the recovery unit? A randomized control trial.

Purpose: While surgeons agree that perioperative field blocks should be performed for open inguinal hernia surgery, there lacks consensus in the minimally invasive context. Prior small-scale randomized trials study pain scores only up to 24 h postoperatively. Thus, we sought to investigate the analgesic benefits of a bupivacaine transversus abdominis plane (TAP) block in the first 4 postoperative days.

Methods: This is a prospective single-institution randomized control trial involving patients undergoing elective totally extraperitoneal inguinal hernia repairs, who received either a TAP block with bupivacaine 0.25% or saline placebo. Postoperatively, patients completed a pain survey (based on a 0-10 visual analog score) and an opioid/non-opioid pain medication log. Differences were detected using a Wilcoxon rank sum test for continuous variables, and a Fisher's exact test or chi-squared for categorical variables.

Results: A total n = 90 patients were included in the per-protocol analysis, of which n = 46 received TAP blocks with bupivacaine versus n = 44 placebo. Patient characteristics were similar between the groups, including recurrent hernias and number of tacks placed (p > 0.05). All cases were bilateral. Postoperatively, pain scores (at rest and with movement) and pain medication use were similar for all postoperative days 1-4.

Conclusion: Our study shows no significant difference in pain or opioid requirement within the first 4 days postoperatively, suggesting that the analgesic benefits of plain bupivacaine TAP blocks in totally extraperitoneal inguinal hernia repairs do not exist beyond the recovery unit. This will help inform anesthesiologists and patients in discussing risks and benefits of a TAP block in their surgical context.