Analgesic Effects of Intravenous Lidocaine in Laparoscopic Surgery: A Systematic Review and Meta-Analysis With Trial Sequential Analysis.

OBJECTIVES

Recent studies have shown that intravenous lidocaine is associated with reducing postoperative pain. However, the mechanism of action of intravenous lidocaine as a part of a multimodal analgesic regimen on patients undergoing laparoscopic surgery remains unclear. The primary aim was to demonstrate the effects of intravenous lidocaine on postoperative pain scores in adults undergoing laparoscopic surgery.

METHODS

Databases of MEDLINE, EMBASE, and CENTRAL were searched from 1947 to May 2023. Randomized clinical trials (RCTs) comparing intravenous lidocaine and placebo in adults undergoing surgery were included.

RESULTS

Forty-five RCTs (n=2599 patients) were included. The intravenous lidocaine group was associated with statistically significant lower postoperative pain scores at rest (MD: -0.27, 95% CI: -0.45 to -0.08, P =0.005) at the 24-hour after surgery and during movement (MD: -0.58, 95% CI: -0.89 to -0.27, P <0.001). Intravenous lidocaine significantly decreased fentanyl consumption (MD: -14.46, 95% CI: -18.11 to -10.81, P <0.001) and morphine consumption (MD: -3.63, 95% CI: -5.12 to -2.13, P <0.001) postoperatively. It also significantly lowered the incidence of nausea and vomiting (RR: 0.66, 95% CI: 0.54-0.81, P <0.001) and reduced time to flatus (MD: -5.90, 95% CI: -8.18 to -3.62, P <0.001).

DISCUSSIONS: This systematic review reinforces the potential role of adding intravenous lidocaine as part of multimodal analgesia in the reduction of postoperative pain, opioid consumption, incidence of nausea and vomiting, and the time to flatus. However, our findings should be interpreted with caution owing to the low level of evidence and high degree of heterogeneity.