Effect of wound infiltration with ropivacaine or bupivacaine analgesia in breast cancer surgery: A meta-analysis of randomized controlled trials

Background: Although not completely painless, breast-conserving surgery is considerably less painful than modified radical mastectomy. Local anesthetics are speculated to reduce postoperative pain when placed at the surgical site. Thus, we conducted a systematic review of randomized controlled trials to evaluate the efficacy of bupivacaine or ropivacaine analgesia for pain relief in breast cancer surgery. Methods: PubMed, Embase, the Cochrane Library, Scopus, and the ClinicalTrials.gov registry were searched for studies published up to July 2015. Individual effect sizes were standardized, and a meta-analysis was performed to calculate a pooled effect size by using random effects models. Pain was assessed using a visual analog scale at 1, 2, 12, and 24 h postoperatively. The secondary outcomes included complications and analgesic consumption. Results: We reviewed 13 trials with 1150 patients. We found no difference in postoperative pain reduction at 1, 12, and 24 h after breast cancer surgery between the experimental and control groups. The severity of pain was significantly reduced in the experimental group (weighted mean difference -0.19; 95% confidence interval: -0.39-0.00) at 2 h postoperatively. Moreover, postoperative analgesic consumption did not differ significantly between the groups. No major drug-related complication was observed in any study. Conclusion: Administration of the local anesthetics bupivacaine or ropivacaine during breast cancer surgery decreased pain significantly at only 2 h but did not reduce pain at 12, and 24 h postoperatively.