Abstract
BACKGROUND Intravenous (IV) lidocaine has analgesic and anti-inflammatory properties. This study aims to evaluate the efficacy of IV lidocaine in controlling postoperative pain following laparoscopic surgery. METHODS A meta-analysis of randomised controlled trials (RCTs) comparing IV lidocaine versus placebo/routine treatment for postoperative analgesia following laparoscopic surgery. The primary outcome was opiate requirement at 24 h. Secondary outcomes included cumulative opiate requirement, numerical pain scores (2, 12, 24, 48 h at rest and on movement), recovery indices (nausea and vomiting, length of stay, time until diet resumption, first flatus and bowel movement) and side effects (cardiac/neurological toxicity). Subgroup analyses were performed according to operation type and to compare IV lidocaine with intraperitoneal lidocaine. RESULTS Fourteen RCTs with 742 patients were included. IV lidocaine was associated with a small but significant reduction in opiate requirement at 24 h compared with placebo/routine care. IV lidocaine was associated with reduced cumulative opiate requirement, reduced pain scores at rest at 2, 12 and 24 h, reduced nausea and vomiting and a shorter time until resumption of diet. The length of stay did not differ between groups. There was a low incidence of IV lidocaine-associated toxicity. In subgroup analyses, there was no difference between IV and intraperitoneal lidocaine in the measured outcomes. CONCLUSIONS IV lidocaine has a multidimensional effect on the quality of recovery. IV lidocaine was associated with lower opiate requirements, reduced nausea and vomiting and a shorter time until resumption of diet. Whilst IV lidocaine appears safe, the optimal treatment regimen remains unknown. Statistical heterogeneity was high.
