Nasocystic irrigation reduces suprainfection and stent occlusion after LAMS drainage of walled-off necrosis

Background and Objectives: Suprainfection and stent occlusion complicate lumen-apposing metal stent (LAMS) drainage for walled-off necrosis (WON). The aim of this study was to evaluate whether adjunctive nasocystic irrigation improves the clinical efficiency. Methods: Eighty patients with WON underwent endoscopic ultrasonography-guided transgastric LAMS placement and were randomized 1:1 to LAMS alone ( n = 40) or LAMS with twice-daily nasocystic saline irrigation ( n = 40). Primary endpoint was suprainfection within 7 days. Secondary outcomes included stent occlusion, other adverse events, and clinical outcomes including clinical success rate, debridement frequency, duration of LAMS placement, postoperative hospital stay length, postoperative intensive care unit admission, and surgical intervention. Results: Nasocystic irrigation significantly reduced suprainfection (intention-to-treat: 37.5% vs . 55.0%, P = 0.178; as-treated: 34.2% vs. 57.1%, P = 0.044) and stent occlusion rates (intention-to-treat: 20.0% vs . 45.0%, P = 0.032; as-treated: 18.4% vs . 45.2%, P = 0.020). Fewer bleeding events occurred with irrigation (3 vs . 6 cases), though without a significant difference. Clinical success rate increased with nasocystic irrigation in 5% of patients, clinical outcomes including debridement frequency and postoperative intensive care unit admission showed a decreasing trend. Conclusion: Nasocystic irrigation significantly decreases suprainfection and stent occlusion following LAMS placement for WON, and may be attributable to improve clinical outcomes.