Paravertebral block is not superior to the interpectoral and pectoserratus plane block for patients undergoing breast surgery: An updated meta-analysis of randomised controlled trials with meta-regression and trial sequential analysis.

Background: Breast surgery is frequently associated with significant acute postoperative pain, necessitating effective pain management strategies. Both thoracic paravertebral block (PVB) and interpectoral plane and pectoserratus plane (IP+PS) blocks have been used to relieve pain after breast surgery.

Objective: In this systematic review and meta-analysis with trial sequential analysis, we aimed to identify the optimal analgesic technique for achieving effective pain relief in breast surgery. The primary outcome of this study was postoperative opioid consumption expressed as morphine milligram equivalent (MME) at 24 h. Secondary outcomes included resting and movement pain scores at 0, 6, 12 and 24 h, postoperative nausea and vomiting (PONV), and rescue analgesic requirements within the first 24 h.

Design: A meta-analysis of randomised controlled trials (RCTs) with meta-regression and trial sequential analysis (TSA).

Data search: We systematically searched Pubmed, Scopus, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, Google Scholar, Medline (from inception to until 1 October 2024).

Eligibility criteria: RCTs that include patients undergoing breast surgery with PVB or IP+PS block, with no language restriction.

Results: Eighteen RCTs with 924 patients were included. No significant difference in MME consumption at 24 h was observed between the two techniques; mean difference (MD) -1.94 (95% confidence interval (CI) -4.27 to 0.38, P = 0.101). Subgroup analyses revealed a minor advantage for IP+PS in patients without axillary involvement; MD -2.42 (95% CI -3.56 to -1.29, P  < 0.001), though below the threshold of clinical significance. Secondary outcomes, including pain scores, PONV incidence and rescue analgesic requirements were comparable. Trial sequential analysis (TSA) confirmed sufficient sample size, suggesting further studies may not alter conclusions.

Conclusion: PVB and IP+PS blocks offer comparable analgesic efficacy and opioid-sparing effects after breast surgery, with no meaningful differences in 24-h MME consumption, pain scores, or PONV incidence.