Rhomboid intercostal block with subserratus plane block in bariatric surgery: a three-arm prospective randomized comparative study

Background and objectivesBariatric surgery is an effective intervention for managing obesity, yet postoperative pain management remains a significant challenge. Standard analgesic techniques such as patient-controlled analgesia (PCA) and continuous epidural analgesia (CEA) are effective but associated with considerable side effects, including nausea, hypotension, and respiratory depression. This study aimed to evaluate the efficacy and safety of the rhomboid intercostal block combined with subserratus plane block (RISS) compared to PCA and CEA for postoperative analgesia in bariatric surgery.MethodsA prospective randomized comparative study was conducted, enrolling 144 patients undergoing elective bariatric surgery. Participants were randomized into three groups: PCA, CEA, and RISS. Pain scores (numerical rating scale, NRS) at rest and during movement, opioid consumption, and side effects were assessed at 4, 8, 12, and 24 hours postoperatively. Statistical analyses included one-way ANOVA and repeated-measures ANOVA to evaluate the efficacy and non-inferiority of RISS compared to PCA and CEA.ResultsIntraoperatively, the ephedrine dosage (mg) in the PCA and RISS groups was significantly lower than that in the CEA group (P = 0.0003). RISS provided comparable analgesic efficacy to CEA. At 12 hours postoperatively, rest pain scores (NRS) were 3.7 ± 0.4 in the PCA group, 2.7 ± 0.3 in the CEA group, and 2.3 ± 0.3 in the RISS group (P ConclusionRISS is a safe and effective postoperative analgesic technique for bariatric surgery, achieving pain relief comparable to CEA but with fewer side effects, and demonstrating superior outcomes compared to PCA. This study supports the adoption of RISS in clinical practice to enhance postoperative pain management and patient recovery in bariatric surgery.