Analgesic effects of intraperitoneal lidocaine in adults undergoing surgery: a systematic review and meta-analysis with trial sequential analysis

The administration of local anesthesia in intraperitoneal space as part of the multi-modal analgesic regimen has shown to be effective in reducing postoperative pain. Recent studies demonstrated that intraperitoneal lidocaine may provide analgesic effects. Primary objective was to determine the impact of intraperitoneal lidocaine on postoperative pain scores at rest. We carried out a systematic review and meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Databases of MEDLINE, EMBASE, and CENTRAL were searched from their inception date until May 2023. Randomized clinical trials (RCT) comparing intraperitoneal lidocaine and placebo in adults undergoing surgery were included. Our systematic review included 24 RCTs (n = 1824). The intraperitoneal lidocaine group was significantly associated with lower postoperative pain scores at rest (MD, -0.87, 95% CI, -1.04 to -0.69) and at movement (MD, -0.50, 95% CI, -0.93 to -0.08) among adult patients after surgery. Its administration also significantly decreased morphine consumption (MD, -6.42 mg, 95% CI, -11.56 to -1.27) and lowered the incidence of needing analgesia (OR, 0.22, 95% CI, 0.14 to 0.35). Intraperitoneal lidocaine statistically reduced time to resume regular diet (MD, 0.16 days; 95% CI, -0.31 to -0.01) and lowered postoperative incidence of nausea and vomiting (OR, 0.54, 95% CI, 0.39 to 0.75). In this review, our findings should be interpreted with caution. Future studies are warranted to determine the optimal dose of administering intraperitoneal lidocaine among adult patients undergoing surgery.