Concurrently, in a multicenter, international, retrospective study of 189 patients at 14 centers with WON comparing LAMS and plastic stents, there was a significantly higher clinical success rate with use of LAMS (80.4% vs. 57.5%; P = 0.001) with similar rates of need for percutaneous drainage and a greater need for surgery in the plastic stent group. Of note, the rate of WON recurrence following initial clinical success was significantly greater in the plastic stent group compared to LAMS (22.9% vs. 5.6%; p = 0.04), with the conclusion that LAMS was associated with higher clinical success, short procedural time, decreased need for surgery, and decreased overall rate of recurrence [38]. Interestingly, in a cost‐effectiveness analysis comparing LAMS with plastic stents for WON, LAMS were found to be more effective than plastic stents (92% vs. 84%), though LAMS were markedly more expensive ($US20 029 vs. $US15 941). This cost‐effectiveness modeling favored LAMS, with an incremental cost‐effectiveness ratio of $US49 214 in order to perform one additional successful drainage using LAMS compared to plastic stents, which was confirmed on sensitivity analyses [39].
Lastly, once endoscopic access into the collection has been obtained, there are multiple tools at the endoscopist’s disposal to enable endoscopic debridement and necrosectomy. Some of the most common tools include use of rat‐tooth forceps, snare, and Roth nets to remove pieces of debris. Biliary extraction baskets are also frequently used to this end point. There remains significant opportunities for innovation in this field as currently available tools are adapted to fit new indications and situations.
Conclusion
Patients with acute pancreatitis complicated by WON may be asymptomatic or may have significant symptoms with critical illness. Historically, these patients underwent open necrosectomy when they were symptomatic and critically ill, especially in the setting of concern for infected necrosis; however, this was associated with significant morbidity and mortality and overall poor outcomes long term. Over the past two decades, the pendulum has shifted, and there is now significant data to support the use of step‐up approaches focusing on endoscopic and percutaneous drainage with avoidance of surgical debridement in the early stages and only using minimally invasive surgical options for treatment failures. As the ability to perform endoscopic access of these collections has improved, multiple tools have been added to the endoscopist’s armamentarium to access and debride these lesions, with substantial data favoring the use of minimally invasive approaches. Most recently, the advent of LAMS has again markedly altered management strategies by enabling ongoing access to these collections with wider tracts and decreased risk of migration. Though LAMS are physically more costly than plastic stents, these costs are often mitigated by a variety of other factors, often favoring the use of LAMS as the preferable access option endoscopically. Finally, no matter what the interventional strategy, patients with WON have substantially benefited from multidisciplinary team management.
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