Efficacy and safety of rhomboid intercostal block for analgesia in breast surgery and thoracoscopic surgery: a meta-analysis

BACKGROUND: Rhomboid intercostal block (RIB) is a new regional anesthesia technique that provides postoperative analgesia for breast surgery and thoracoscopic surgery. The published papers are not yet fully integrated and do not adequately address the impact and safety of the RIB on postoperative pain. METHODS: The PubMed, Web of Science and Embase were searched from 2016 to 2021 for all available randomized controlled trials (RCTs) that evaluated the analgesic efficacy and safety of RIB after thoracic surgery and breast surgery. Random and fixed-effects meta-analytical models were used where indicated, and between-study heterogeneity was assessed. The primary outcome was Postoperative Numerical Rating Scale (NRS) scores of patients at rest recorded 0–1, 6–8, 24 h after surgery. The secondary outcomes included rate of postoperative nausea and vomiting (PONV), postoperative fentanyl consumption and presence of complications of the block. RESULTS: From 81 records identified, four studies met our inclusion criteria, including 216 patients (RIB:108 patients; no block: 108 patients). In the primary outcome, RIB group showed significantly lower postoperative NRS at rest at first 0–1 h and 6–8 h (weighted mean difference [WMD] = -1.55; 95% confidence internal [CI] = -2.92 to -0.19; p < 0.05), (WMD = -0. 69; 95% CI = -1.29 to -0. 09; p < 0. 05). And there was no significant difference between groups in NRS at rest at 24 h (WMD = -0.78; 95% CI = -1.64 to -0.08; p = 0.77). Also, RIB group showed significantly lower postoperative NRS of breast surgery and thoracoscopic surgery at 0-1 h (WMD = -3.00; 95% CI = -3.13 to -2.87; p < 0.01), (WMD = -1.08; 95% CI = -1.98 to -0.18; p < 0.05). In the secondary outcome, the analysis also showed RIB group had significant lower of POVN rates (summary relative risk (RR) = 0.212;95%CI = 0.10 to 0.45; p < 0. 01) and the postoperative consumption of fentanyl (WMD = -57.52;95%CI = -106.03 to -9.02; p < 0. 05). CONCLUSION: This review shows that RIB was more effective in controlling acute pain after breast surgery and thoracoscopic surgery than general analgesia. And it is a trend that RIB may be a kind of effective and safe nerve bock technology and it requires further studies.