Erector Spinae Plane Block and its Impact on Postoperative Diaphragmatic Dysfunction in Morbidly Obese Patients Undergoing Laparoscopic Sleeve Gastrectomy: A Double-Blind Randomized Control Trial

BACKGROUND: Postoperative diaphragmatic dysfunction (PODD) is a serious sequela following laparoscopic surgery, particularly in individuals with class III obesity. We aimed to evaluate the efficacy of erector spinae plane block (ESPB) in reducing the incidence of PODD and postoperative pulmonary outcomes in individuals with class III obesity undergoing laparoscopic sleeve gastrectomy. METHODS: This randomized controlled trial included 81 participants living with obesity with a body mass index (BMI) greater than 40 who underwent sleeve gastrectomy. Participants were randomly allocated to the control group or the ESPB group. The primary outcome was the incidence of postoperative diaphragmatic dysfunction, defined as mean diaphragmatic excursion (MDE) < 10 mm at 2 h postoperatively. Secondary outcomes included pulmonary function tests, specifically forced expiratory volume at one second, forced vital capacity, and peak expiratory flow rate, as well as pain scores, nalbuphine consumption, and the ROX index. An experienced operator evaluated diaphragmatic excursion, and the mean diaphragmatic excursion was calculated as the average of the right and left hemidiaphragms. RESULTS: The incidence of PODD was significantly lower in the ESPB group compared to controls (10% vs. 73%). ESPB recipients demonstrated higher diaphragmatic excursion, pulmonary function parameters, and reduced pain scores and opioid consumption. A strong positive correlation (r = 0.786) was found between diaphragmatic excursion and ROX index at 2 h postoperatively. CONCLUSION: Bilateral ESP block in individuals with class III obesity undergoing sleeve gastrectomy significantly reduces the incidence of postoperative diaphragmatic dysfunction, preserves pulmonary function, and reduces postoperative nalbuphine consumption. These findings support the integration of erector spinae plane blocks into multimodal perioperative strategies to enhance respiratory outcomes and patient comfort in patients living with obesity undergoing metabolic bariatric surgery.