Comparisons in Analgesic Effects Between Ultrasound-Guided Erector Spinae Plane Block and Ultrasound-Guided Modified Intercostal Nerve Block in Modified Radical Mastectomy: A Randomized Controlled Trial

Abstract

Introduction Postoperative acute pain is a common challenge after breast cancer surgery. This randomized controlled trial compared the analgesic effects of ultrasound-guided erector spinae plane block (ESPB) and modified intercostal nerve block (MINB) in patients undergoing unilateral modified radical mastectomy. Methods Seventy patients were randomly allocated to ESPB or MINB group. The primary outcomes were the 6-hour postoperative resting and movement-evoked Visual Analogue Scale (VAS) scores. Secondary outcomes included resting and movement-evoked VAS scores at 0, 3, 12, and 24 hours, intraoperative opioid consumption, rescue analgesic use within 72 hours, Quality of Recovery-15 (QoR-15) score at 24 hours, and hospital stay. Results At 6 hours postoperatively, both resting VAS (median 2 [0–2] vs 2 [2–3], P=0.005) and movement-evoked VAS (median 3 [2–4] vs 4 [3–4], P=0.015) were lower in the MINB group. Resting VAS scores at 0 and 3 hours were comparable between groups. Movement-evoked VAS scores were lower in the MINB group at all post-surgery time points (P<0.05 for all). Intraoperative remifentanil consumption was lower in the MINB group (P<0.001). Fewer patients required rescue analgesics in the MINB group (P=0.038). No significant difference was observed in QoR-15 scores between groups (P=0.055). Conclusion Ultrasound-guided MINB was associated with lower 6-hour resting and movement-evoked pain scores and reduced intraoperative opioid consumption compared with ESPB, without compromising recovery quality in patients undergoing unilateral modified radical mastectomy. Trial Registration Chinese Clinical Trial Registry (ChiCTR2300077956; https://www.chictr.org.cn/showproj.aspx?proj=77956). Registered on November 24, 2023. Principal investigator: Guanghong Xu.