Abstract
Background: Transverse abdominal plane (TAP) blocks are used to provide pain relief after abdominopelvic surgeries. The role of liposomal bupivacaine (LB) for TAP blocks is unclear. Therefore, this study aimed to synthesize evidence on the efficacy of LB vs. regular anesthetics in improving outcomes of TAP block. Methods: PubMed, Science Direct, Embase, Springer, and CENTRAL databases were searched up to July 24, 2020. Studies comparing LB with any regular anesthetic for TAP block for any surgical procedure and reporting total analgesic consumption (TAC) or pain scores were included. Results: Seven studies including five randomized controlled trials (RCTs) were reviewed. LB was compared with regular bupivacaine (RB) in all studies. A descriptive analysis was conducted for TAC due to heterogeneity in data presentation. There were variations in the outcomes of studies reporting TAC. Meta-analysis of pain scores indicated statistically significant reduction of pain with the use of LB at 12 h (MD: -0.89 95% CI: -1.44, -0.34 I(2) = 0% p = 0.01), 24 h (MD: -0.64 95% CI: -1.21, -0.06 I(2) = 0% p = 0.03), 48 h (MD: -0.40 95% CI: -0.77, 0.04 I(2) = 0% p = 0.03) but not at 72 h (MD: -0.37 95% CI: -1.31, 0.56 I(2) = 57% p = 0.43). Pooled analysis indicated no difference in the duration of hospital stay between LB and RB (MD: -0.18 95% CI: -0.49, 0.14 I(2) = 61% p = 0.27). LB significantly reduced the number of days to first ambulation postsurgery (MD: -0.28 95% CI: -0.50, -0.06 I(2) = 0% p = 0.01). Conclusions: Current evidence on the role of LB for providing prolonged analgesia with TAP blocks is unclear. Conflicting results have been reported for TAC. LB may result in a small reduction in pain scores up to 48 h but not at 72 h. Further, high-quality homogenous RCTs are needed to establish high-quality evidence.