Perioperative systemic lidocaine for postoperative analgesia and recovery after abdominal surgery: a meta-analysis of randomized controlled trials.

BACKGROUND: Postoperative pain management remains a significant challenge after abdominal surgery.
OBJECTIVE: The aim of this meta-analysis was to evaluate the efficacy of systemic lidocaine for postoperative pain management and recovery after abdominal surgery. DATA SOURCE: Data were derived from Medline (1966-2010), CINAHL, The Cochrane Central Register of Controlled Trials, and Scopus. STUDY SELECTION: Randomized controlled trials of systemic administration of lidocaine for postoperative analgesia and recovery after abdominal surgery in adults, ie, >18 years, were considered.
INTERVENTIONS: Combined data were analyzed with use of a random-effects model. MAIN OUTCOMES MEASURES: Data on opioid consumption, postoperative pain intensity, opioid-related side effects, time to first flatus, time to first bowel movement, and length of hospital stay were extracted.
RESULTS: Twenty-one trials comparing systemic lidocaine with placebo or blank control for postoperative analgesia and recovery after abdominal surgery were included in this meta-analysis. Weighted mean difference for cumulative analgesic opioid (morphine) consumption 48 hours after surgery was -7.04 mg (95% CI: -10.40, -3.68, I2= 46.1%).Systemic lidocaine also significantly reduced postoperative pain intensity(visual analog scale, 0-100 mm) 6 hours after surgery at rest (weighted mean difference: -8.07 mm (95% CI: -14.69, -1.49); I2 = 90.6%) and during activity (weighted mean difference: -10.56 mm (95% CI: -16.89, -4.23), I2 = 82%). The time to first flatus and bowel movement was significantly shortened with lidocaine intervention by 6.92 hours (95% CI: -9.21, -4.63, I2 = 62.8%) and 11.74 hours (95% CI:-16.97, -6.51, I2 = 0). Moreover, systemic lidocaine also reduced hospital length of stay following the open procedure (weighted mean difference: -0.71 days (95% CI: -1.35, -0.07); I2 = 37.3%). LIMITATIONS: Heterogeneity of study results is the main limitation of this meta-analysis.
CONCLUSION: Perioperative systemic lidocaine may be a useful adjunct for postoperative pain management by decreasing postoperative pain intensity, reducing opioid consumption, facilitating GI function, and shortening length of hospital stay.