Do TEP and TAPP have similar effect on postoperative pain?

Abstract

Dear Editor, We read with interest an article entitled “Total extraperitoneal (TEP) versus laparoscopic transabdominal preperitoneal (TAPP) hernioplasty: systematic review and trial sequential analysis of randomized controlled trials” by Aiolfi et al. in Hernia [1]. As efficacy and safety of the two laparoscopic inguinal herniorrhaphy approaches have been discussed for a long time, the authors attempted to give a conclusive evidence using trial sequential analysis (TSA). We appreciate an appropriate use of TSA on this topic, and agree with the finding concerning comparable hernia recurrence rates between TEP and TAPP. However, some concerns would be raised with a missed randomized controlled trial (RCT) [2]. Bansal et al. published two articles for two RCTs in 2013 and 2016, respectively [2, 3]. The article published in 2013 reports a RCT between May 2007 and April 2012 [3], and the other article is published for another RCT between April 2012 and October 2014 [2]. The meta-analysis by Aiolfi et al. only includes the RCT in 2013 [1, 3], and the missed evidence may affect the findings, particularly about postoperative pain due to significant difference between TEP and TAPP in the RCT [2]. It is necessary to have a further analysis to confirm the effect of the two laparoscopic herniorrhaphy procedures on postoperative pain based on all available evidence. Since there are pooled estimates for pain scores without mean and standard deviation of each included trials in the reports by Aiolfi et al. [1], we updated meta-analysis using available data of pain scores from the synthesis by Aiolfi et al. and the reports of the RCT by Bansal et al. in 2016 [1, 2]. Pooled results appear to show that patients after TEP had lower pain score than those receiving TAPP at week 1 (weighted mean difference [WMD], − 0.69; 95% confidence interval [CI] − 1.17 to − 0.22), month 1 (WMD, − 0.36; 95% CI − 0.62 to − 0.11), and month 3 (WMD, − 0.31; 95% CI − 0.56 to − 0.06). We know that early postoperative pain of laparoscopic surgery was composited of multiple factors [4], yet mainly depended on the anatomical dismantlement and reorganization within the procedure. The foremost difference between TEP and TAPP repair is violation to peritoneum, where meticulous nerves and vessels clang on. Moreover, in TAPP, peritoneal incision, peritoneal irritation and suture of peritoneum might all stirred up noxious stimuli, which took time to digest. Less short-term postoperative pain in TEP than in TAPP repair was derivation of surgical anatomy and statistics [5]. Our findings indicate that pooled estimates would be affected by the missed evidence, and reflect the importance of comprehensive inclusion before TSA. If the authors completely update analyses with data from the RCT by Bansal et al. in 2016 [2], the findings would be more appropriate than the present estimates (Fig. 1). Correspondence on Aiolfi et al. Total extraperitoneal (TEP) versus laparoscopic transabdominal preperitoneal (TAPP) hernioplasty: systematic review and trial sequential analysis of randomized controlled trials. Hernia. 2021.