Comparison of Ultrasound-Guided M-TAPA and OSTAP Blocks for Postoperative Analgesia in Laparoscopic Sleeve Gastrectomy: A Randomized Controlled Trial

Background: Laparoscopic sleeve gastrectomy (LSG) is a widely performed procedure for obesity management, and effective postoperative pain control remains a significant challenge. Ultrasound-guided regional blocks, as part of a multimodal analgesia approach, have recently gained prominence in improving postoperative outcomes. This study evaluates the comparative efficacy of modified thoracoabdominal plane block with perichondrial approach (M-TAPA) and oblique subcostal transversus abdominis plane (OSTAP) blocks, specifically addressing the role of ultrasound guidance in enhancing postoperative pain management in patients undergoing LSG. Methods: This prospective, single-center randomized study included 60 patients (M-TAPA [ n = 30] and OSTAP [ n = 30]) scheduled for LSG. The primary outcome was tramadol consumption via patient-controlled analgesia. Secondary outcomes included the Numeric Rating Scale for pain, postoperative nausea and vomiting, additional analgesic requirements, and block execution time. Results: At the 6-h postoperative mark, tramadol consumption in the M-TAPA group was significantly lower than in the OSTAP group ( p = 0.009). Total tramadol consumption over 24 h was found to be lower in the M-TAPA group (280 ± 89.08 mg) than in the OSTAP group (325.5 ± 100.21 mg). The difference was close to the statistical significance limit ( p = 0.058). Conclusion: These findings support the growing role of ultrasound-guided regional techniques in enhancing multimodal analgesia in bariatric surgery, particularly in obese patients.