Transversus abdominis plane (TAP) block for postoperative pain management after ventral hernia repair: an updated systematic review and meta-analysis

Background Postoperative pain remains a common concern following ventral hernia repair (VHR), especially for open procedures. We aim to assess the effectiveness of the Transversus Abdominis Plane (TAP) block for the management of postoperative pain following VHR. Methods Cochrane, EMBASE, and PubMED, MEDLINE, and Web of Science were systematically searched for studies comprising adults undergoing VHR with preoperative TAP block, compared to placebo and epidural analgesia. The outcomes selected for analysis were postoperative pain with the numeric rating scale (NRS), postoperative morphine milligram equivalents (MME) per day, and hospital length of stay (LOS). Subgroup analysis was performed for studies using the Liposomal Bupivacaine (Exparel (R)) for TAP block. Results 1,460 results were screened, and 14 included, comprising 9 retrospective cohort studies and 5 RCTs, totaling 1,617 patients. TAP block was associated with a shorter LOS compared to conventional pain measures (MD -1,14 days; 95% CI -2.05, -0.22; P = 0.014) and to epidural analgesia (MD -2.02 days; 95% CI -2.67, -1.37; P < 0.001), and lower NRS scale in the day of surgery (MD -1.24; 95% CI -1.81, -0.68; P < 0.001) and in the POD1 (MD -0.63; 95% CI -1.18, -0.08; P = 0.025) compared to placebo. No benefit was seen for TAP block regarding opioid consumption compared to epidural analgesia and placebo. No differences were seen between TAP block and epidural analgesia for the NRS scores. Subgroup analysis of Exparel (R) compared to simple bupivacaine showed no benefit for Exparel (R). Conclusions The TAP block is associated with shorter LOS compared to placebo and epidural analgesia and is related to less early postoperative pain compared to the conventional pain measures. The TAP block should be considered as a pain management modality for VHR, however cost-effective analysis is required to address the feasibility of the routine utilization of this approach and to balance the financial benefits of its application.