Quality of Recovery After Primary Breast Cancer Surgery: A Randomized, Two-Centre, Triple-Blinded Trial Comparing Erector Spinae Plane Block and Intravenous Lidocaine Infusion Within a Multimodal Analgesia Framework.

BACKGROUND: The erector spinae plane block (ESPB) is widely used for primary breast cancer surgery (BCS), though its clinical benefits within optimized multimodal analgesia pathways remain uncertain. Intravenous lidocaine infusion (IVLI) offers a simple, reproducible alternative with potential systemic analgesic effects. This randomized, tripleblinded, placebo controlled, twocentre trial compared the quality of recovery after ESPB versus IVLI for BCS. METHODS: Eighty adult patients undergoing primary BCS, with or without axillary dissection, were randomized to receive either ultrasoundguided ESPB (n=40) or intraoperative IVLI (n=40), in addition to a standardized multimodal analgesic protocol. The primary outcome was quality of recovery (QoR15) score at 24 hours. Secondary outcomes included postoperative pain scores, opioid consumption, adverse events, and rescue analgesia requirements. RESULTS: Both interventions produced excellent postoperative recovery, with 24hour QoR15 scores approaching preoperative baselines with no significant difference between groups (mean (SD) 24-hour QoR score; ESPB vs. IVLI group, 137.7(17.9) vs. 136.3(8.8), p=0.61). Pain burden and analgesic requirements over the first 24 hours were similarly low, and no ESPB or lidocainerelated adverse events were observed. CONCLUSIONS: Within a standardized multimodal analgesic framework, postoperative recovery and analgesic outcomes did not differ significantly between IVLI and ESPB, suggesting that IVLI may offer a pragmatic alternative when regional anesthesia expertise is limited.