Evidence for regional block-based analgesia in robot-assisted transaxillary thyroidectomy: a systematic review and meta-analysis.

To evaluate the analgesic effectiveness of perioperative regional nerve blocks after robot-assisted transaxillary thyroidectomy. A comprehensive search of PubMed, Embase, the Cochrane Library, and Web of Science was performed from database inception through December 31, 2025. Methodological quality was evaluated with the revised Cochrane risk-of-bias tool (RoB 2) for randomized controlled trials and the Newcastle-Ottawa Scale for the retrospective cohort study. Statistical synthesis was performed in Stata version 18.0. Continuous outcomes were pooled as weighted mean differences (WMDs), whereas dichotomous outcomes were expressed as odds ratios (ORs), with both effect measures reported alongside their corresponding 95% confidence intervals. The final analysis included four studies-three randomized controlled trials and one retrospective cohort study-encompassing 224 patients, of whom 113 received a regional nerve block and 111 served as controls; all evaluated robot-assisted thyroidectomy performed via a transaxillary approach. Perioperative nerve blocks were associated with lower visual analog scale (VAS) pain scores at 4 h (WMD = - 1.44, 95% CI: -2.43, - 0.45; P = 0.005), 24 h (WMD = - 1.28, 95% CI: -1.74, - 0.82; P < 0.001), and 48 h (WMD = - 0.47, 95% CI: -0.79, - 0.14; P = 0.005), as well as lower post-anesthesia care unit (PACU) pain scores (WMD = - 2.68, 95% CI: -3.31, - 2.06; P < 0.001). Nerve blocks were associated with a modest increase in operative time (WMD = 2.67, 95% CI: 0.04, 5.30; P = 0.047). Current evidence suggests that perioperative regional nerve blocks may improve postoperative analgesia after robot-assisted transaxillary thyroidectomy, with larger reductions in pain scores during the first 24 h and a smaller between-group difference at 48 h. However, larger randomized trials are needed to confirm these findings.