Abstract
BACKGROUND: Rectus sheath block (RSB) provides reliable anesthesia to the anteromedial abdominal wall and may offer effective pain control following laparoscopic sleeve gastrectomy (LSG). This study aimed to compare the efficacy of RSB versus local infiltration analgesia (LIA), hypothesizing that RSB would provide superior pain relief. METHODS: In this randomized controlled trial, patients with obesity undergoing LSG received either bilateral ultrasound-guided RSB performed by an anesthesiologist or LIA administered by a surgeon, following anesthesia induction. The primary outcome was intraoperative fentanyl consumption. Secondary outcomes included postoperative pain scores [Numeric Rating Scale (NRS), 0-10], cumulative morphine consumption, and recovery metrics over 48 h. RESULTS: Sixty-nine patients were analyzed (RSB: 35; LIA: 34). Intraoperative fentanyl use was lower with RSB (median difference: - 25 mcg; 95% CI: - 50 to 0; p = 0.008). RSB reduced pain scores at rest at 0 h (-2 points; p = 0.001), 1 h (-1 point; p = 0.009), and 12 h (-1 point; p = 0.022), and pain during movement at 0 h (-3 points; p < 0.001), 12 h (-1 point; p = 0.043), and 36 h (-1 point; p = 0.019). Pain scores were otherwise comparable. Fewer RSB patients reported moderate-to-severe pain at 0 h and 1 h (rest: p = 0.006 and 0.019; movement: p < 0.001 and 0.033). Postoperative morphine use and recovery metrics were similar between groups. CONCLUSION: Pre-incisional RSB demonstrated an intraoperative opioid-sparing effect and superior early postoperative analgesia compared with LIA, supporting its role as a component of multimodal analgesia for LSG.