Abstract

BACKGROUND: To investigate the non-inferiority of ultrasound-guided rhomboid intercostal and subserratus plane (RISS) block compared to thoracic paravertebral block (TPVB) in postoperative analgesia for thoracoscopic surgeries.METHODS: This study consecutively enrolled 50 patients undergoing elective thoracoscopic surgery. Following general anesthesia, the RISS group received a unilateral block with 40 mL of 0.25% ropivacaine, while the TPVB group received with 30 mL of 0.33% ropivacaine. The primary outcome measure was the 24-hour postoperative resting VAS score. Secondary outcome measures included nerve block operation time for two groups, postoperative 1, 2, 4, 8, 48-hour resting VAS scores, and different time points coughing VAS scores, time to first postoperative ambulation, total intravenous analgesic consumption at different time points postoperatively, complications related to the block.RESULTS: There were no significant statistical differences between the two groups in terms of postoperative rest and cough VAS scores at each time (P>0.05), and the mean difference in rest VAS scores did not exceed the non-inferiority margin in 95% CI. There were no significant differences in total intraoperative and postoperative analgesic consumption at different time points (P>0.05), and no significant differences in time to first postoperative ambulation (P>0.05). Compared to the TPVB group, the RISS group had a shorter nerve block operation time (259.43±30.11 vs. 335.23±30.96 s, P<0.001) and fewer instances of intraoperative hypotension (two vs. seven cases, P=0.022), bleeding at the puncture site, pneumothorax, and arrhythmia.CONCLUSIONS: In thoracoscopic surgeries, the postoperative analgesic efficacy of ultrasound-guided RISS block is not inferior to TPVB. Compared to TPVB, RISS block is simpler, quicker, and associated with fewer puncture-related complications.