Preservation Breast Augmentation Under Sedation Is a Low-Pain Procedure: A Randomized Controlled Trial of Serratus Anterior Plane Block as an Adjunct

Abstract Background Preservation breast augmentation (PBA) is an intralamellar technique preserving the pectoralis major muscle, circummammary ligament, and Cooper's suspensory ligaments. Its perioperative pain profile and the value of regional anesthesia adjuncts remain uncharacterized. Objectives To characterize the perioperative pain profile of PBA under local anesthesia and sedation, and to determine whether a preoperative deep SAP block reduces intraoperative analgesic requirements and early postoperative pain. Methods This prospective, randomized, single-blind trial enrolled 40 women undergoing PBA. Patients were randomized 1:1 to a preoperative deep SAP block (20 mL of 0.25% bupivacaine bilaterally) or standard care; all procedures used tumescent local anesthesia and propofol sedation. Endpoints included 24-hour NRS score, rescue propofol and fentanyl consumption, hemodynamic response, and postoperative analgesic use. Results Baseline characteristics were comparable. The SAP group required less rescue propofol (45 ± 3 vs. 55 ± 4 mg; p < 0.001; d = 2.83) and fentanyl (12 ± 5 vs. 22 ± 9 µg; p < 0.001; d = 1.37). NRS scores favored the SAP group at 60 min (3.4 vs. 4.5; p = 0.011) and 6 h (3.8 vs. 4.7; p = 0.035), converging by 24 h (3.4 vs. 3.2; p = 0.377); both groups remained within a low pain range (NRS ≤ 3.5). No major complications occurred. Conclusions PBA under local anesthesia and sedation is associated with a consistently low perioperative pain profile. The SAP block provides a clinically meaningful intraoperative analgesic advantage and improves early postoperative comfort, supporting selective rather than routine use.