Continuous Wound Infiltration with Local Anesthetic Is an Effective and Safe Postoperative Analgesic Strategy: A Meta-Analysis

Plain Language Summary Continuous wound infiltration (CWI) with local anesthetic may be a promising postoperative analgesic strategy, but its effect remains debatable. We performed this meta-analysis based on 121 high-quality articles (RCTs) to evaluate the analgesic efficacy and safety of CWI with local anesthetic. We found that CWI with local anesthetic could reduce postoperative pain, increase satisfaction with analgesia, shorten recovery of bowel function, and reduce postoperative nausea and vomiting, especially for laparotomy surgery. However, CWI with local anesthetic did not show favorable analgesic benefits in laparoscopic surgery. Introduction Postoperative pain management is an essential module for perioperative care, especially for enhanced recovery after surgery programs. Continuous wound infiltration (CWI) with local anesthetic may be a promising postoperative analgesic strategy. However, its analgesic efficacy and safety remain debatable. Methods Embase and PubMed databases were systematically searched for relevant randomized controlled trials (RCTs). RCTs assessing the analgesic efficacy and safety of CWI with local anesthetic for postoperative analgesia were selected. The outcomes contained pain scores during rest and mobilization, total opioid consumption, time to the first request of rescue analgesia, length of hospital stay, satisfaction with analgesia, time to return of bowel function, postoperative nausea and vomiting, total complication, wound infection, hypotension, and pruritus. The weighted mean difference and risk ratio were used to pool continuous and dichotomous variables, respectively. Results A total of 121 RCTs were included. CWI with local anesthetic reduced postoperative pain during rest and mobilization at different time points, increased satisfaction with analgesia, shortened recovery of bowel function, and reduced postoperative nausea and vomiting compared with the placebo group, especially for laparotomy surgery. There were no significant differences in these clinical outcomes compared to epidural and intravenous analgesia. CWI with local anesthetic reduced the total opioid consumption and hypotension risk and did not increase total complications, wound infection, or pruritus. CWI with local anesthetic had a better analgesic efficacy without increased side effects for sternotomy surgery. However, CWI with local anesthetic did not translate into favorable analgesic benefits in laparoscopic surgery. Conclusion CWI with local anesthetic is an effective postoperative analgesic strategy with good safety profiles in laparotomy and sternotomy surgery, and thus CWI with local anesthetic may be a promising analgesic option enhancing recovery after surgery programs for these surgeries.