Serratus Plane Block in Breast Cancer Surgery: A Systematic Review and Meta-Analysis.

The serratus plane block is a regional anesthesia technique awaiting efficacy and safety evaluation in breast cancer surgery, but evidence is unclear. This meta-analysis evaluates the analgesic effectiveness of serratus plane block vis-à-vis general anesthesia and paravertebral block for breast cancer surgery. We searched for randomized controlled trials in PubMed, the Cochrane Library, and Web of Science with no language limitation, comparing the serratus plane block with multimodal analgesia or the thoracic paravertebral block in breast cancer surgery. The Hartung-Knapp-Sidik-Jonkman method in combination with a random-effects model was used to pool data. We included 12 randomized controlled trials (799 patients). Compared with multimodal analgesia, pooled outcomes favored the use of serratus plane block for effectively alleviating acute postoperative pain severity at multiple time points. The serratus plane block also resulted in decreased postoperative analgesic consumption of 28.81mg (95% confidence interval [CI]: -51.20, -6.43), decreased intraoperative fentanyl consumption of -56.46 mg (95% CI: -79.61, -33.30), increased duration of postoperative anesthesia of 243.85 min (95% CI: 104.38, 383.31), and reduced postoperative nausea and vomiting with a log relative risk of -1.07 (95% CI: -1.90, -0.24). Compared with the thoracic paravertebral block, the serratus plane block was not statically worse for all of the outcomes assessed. No adverse effects were reported. The serratus plane block effectively alleviates acute postoperative pain, reduces the rate of postoperative nausea and vomiting, and improves perioperative anesthesia outcomes in breast cancer surgery, and it may represent an alternative to thoracic paravertebral block.