Dear colleagues,
We continue our theme of highlighting innovations in gastroenterology by exploring how endoscopy continues to blur the lines with surgery. In this issue of Perspectives, Dr. RJ Sealock, assistant professor of medicine at the Baylor College of Medicine, and Dr. Thiru Muniraj, associate professor of medicine at the Yale School of Medicine share their experiences performing minimally invasive alternatives to surgery, discussing both sides of gastrointestinal perforations – treating and creating. Dr. Sealock describes how we can “MacGyver” traditional surgical wound vacs to treat Boerhaave's, while Dr. Muniraj shows how lumen-apposing metal stents allow us to treat acute cholecystitis in poor surgical candidates.
Dr. Gyanprakash Ketwaroo
Gyanprakash A. Ketwaroo, MD, MSc, is associate professor of medicine, Yale University, New Haven, Conn., and chief of endoscopy at West Haven (Conn.) VA Medical Center. He is an associate editor for GI & Hepatology News.
Endoscopic vacuum therapy for GI perforation
BY ROBERT JAY SEALOCK, MD
Gastrointestinal endoscopy has evolved from a diagnostic modality into a therapeutic tool used to treat a wide variety of luminal pathology. Endoscopic closure of full thickness injuries is a field that has rapidly expanded because of advanced endoscopic tissue resection and the need for subsequent defect closure as well as technological advances in closure devices such an endoscopic suturing platforms and large over-the-scope clips.
Dr. Robert Jay Sealock
Prior to the advent of closure devices, endoscopic means of treating full thickness defects included through-the-scope (TTS) clips and fully covered metal stents. Given the small size, TTS clips are useful for mucosal closure but are limited in their ability to achieve full thickness closure. Fully covered metal stents utilized particularly for upper GI tract perforations and leaks are intended to divert gastrointestinal content away from the site of injury, thereby allowing secondary intention healing. Stents have several limitations, including frequent downstream migration and an inability to create a “watertight” seal in minimizing wound contamination. For decades, our surgical colleagues have utilized negative pressure wound therapy or vacuum therapy to expedite large wound closure. Given their familiarity with the technique, surgeons began adapting vacuum therapy for the treatment of postsurgical anastomotic leaks and fistulas particularly within the rectum.1 Eventually, the same technique was applied to the treatment of upper GI tract anastomotic leaks.2 Endoscopic vacuum therapy (EVT) overcomes many of the limitations of traditional endoscopic closure or diversion using covered stents through the use of suction to promote granulation tissue and aspirate infected wound contents.3
The approach to full thickness luminal injury must be individualized, but for a majority of indications EVT can be considered as a first-line approach. In our own experience, EVT closure can be achieved in more than 80% of patients with a variety of injuries such as iatrogenic endoscopic perforations (e.g., esophageal perforation during Savary dilation), surgical defects (sleeve gastrectomy leaks), and spontaneous perforations (e.g., Boerhaave syndrome). The initial step is endoscopic assessment of the luminal injury as well as the extraluminal cavity. In some situations, it is necessary to manually clean the defect cavity of necrotic material and food.
Once the cavity is cleaned and the size of the defect is assessed, the EVT device is manufactured at the bedside using commonly available materials and tools. A wound vacuum polyurethane sponge is affixed to a nasogastric tube, trimmed to the desired shape and size, and placed either within the defect cavity or within the GI lumen next to the defect opening.4 The EVT device is exchanged at an interval of 3-5 days, which allows the promotion of granulation tissue and subsequent downsizing as the cavity shrinks. In our series, an average number of five exchanges was necessary to achieve closure, with an average time to closure of 25 days.
Most experts would recommend initially placing the EVT device within the defect cavity. Once the cavity size can no longer accommodate the device, complete closure is achieved via intraluminal placement. The use of constant negative pressure (typically 150 mm to 175 mm Hg) prevents migration or dislodgement of the device.
For those who use EVT, there is some satisfaction from assembling and tailoring your own device, much like the protagonist in the 1980s television series “MacGyver,” who would manufacture devices out of readily available materials to address difficult and life-threatening situations. This need for self-assembly also has fostered ingenuity and creativity in the field, which can be found in social media and peer-reviewed sources.5 For some, however, the need to assemble your own device may be a deterrent. There is certainly an opportunity for commercialization and innovation, thereby putting Food and Drug Administration–approved devices into the hands of endoscopists. EVT is also a time- and labor-intensive therapy without specific reimbursement codes. Despite these limitations we continue to use and advocate for EVT given its clinical success in a population of patients with complex luminal injuries.
Dr. Sealock is assistant professor of medicine, department of gastroenterology and hepatology, Baylor College of Medicine, Houston. He receives research funding from AbbVie and is a consultant to ConMed and Ambu.
References
1. Weidenhagen R et al. Endoscopic vacuum-assisted closure of anastomotic leakage following anterior resection of the rectum: A new method. Surg Endosc Other Interv Tech. 2008;22(8):1818-25. doi: 10.1007/s00464-007-9706-x.
2. Wedemeyer J et al. Endoscopic vacuum-assisted closure of upper intestinal anastomotic leaks. Gastrointest Endosc. 2008;67(4):708-11. doi: 10.1016/j.gie.2007.10.064.
3. Mennigen R et al. Comparison of endoscopic vacuum therapy versus stent for anastomotic leak after esophagectomy. J Gastrointest Surg. 2015;19(7):1229-35.
4. Abdulsada M et al. Endoluminal vacuum therapy of esophageal perforations. VideoGIE. 2020;5(1):8-10. doi: 10.1016/j.vgie.2019.10.004
5. de Moura DTH et al. Cost-effective modified endoscopic vacuum therapy for the treatment of gastrointestinal transmural defects: Step-by-step process of manufacturing and its advantages. VideoGIE. 2021 Sep 4;6(12):523-8. doi: 10.1016/j.vgie.2021.08.002.
