Table 2.

Endoscopic Devices Used for the Drainage of Transmural Defects

Device/ Technique	Mechanism of action	Description	Best use	Defect characteristics for success	Advantage (s)	Disadvantage (s)
Septotomy	Draining	Frequently a septum is identified between the leak site (cavity) and gastric pouch. Sequential incisions can be performed using APC or electrical surgical knives over the septum towards to the staple line to allow communication between the extraluminal cavity (leak/fistula site) and the gastric lumen.	Chronic leaks and fistulas	Location/distance from the entrance orifice: anywhere in the GI tract that has a “septum”. Most commonly after sleeve gastrectomy leaks. Size: any size Margin: non-everted or everted edges Tissue quality: healthy or unhealthy (fibrotic)	Low cost procedure Easily performed	Just for selective cases (presence of “septum”)
Pigtail stents (Endoscopi c Internal drainage)	Draining	Guide the drainage towards the GI tract (internal drainage (ID)) while favoring the leak/fistula’s occlusion. The purpose is threefold: 1) help drain the cavity; 2) obstruct orifice and enable oral intake; 3) induce mechanical reepithelization (as a foreign body) in order to produce healing along the defects pathway. If an external drain is present it must be capped or removed.	Acute and chronic leaks and fistulas	Location/distance from the entrance orifice: anywhere in the GI tract Size: any size, including large cavities Margin: non-everted or everted edges Tissue quality: healthy or unhealthy	Can be applied at complex wall defect geometry Low cost procedure Easily to perform	Repeat procedures for stent exchanges
Endoscopic Vaccuum Therapy (EVT)	Draining	Consists of placing a sponge in the lumen (or in the abscess cavity) connected with a NG tube to a negative pressure system (− 125 mmHg). It seals the leak and decreases bacterial contamination promoting perfusion and granulation tissue proliferation.	Acute and chronic leaks and fistulas	Location/distance from the entrance orifice: anywhere in the GI tract that the vacuum catheter can reach Size: any size, including large cavities Margin: non-everted or everted edges Tissue quality: unhealthy	Sponge system can be customized for the defect/ Cavity	Repeat procedures every 4–5 days Risk of massive bleeding
Balloon dilation	Dilation of downstrea m stenosis is critical for leak resolution	The pneumatic achalasia balloon (AB) is used for dilation of sleeve stenosis downstream of the leak/fistula to promote antegrade flow and drainage. The hydrostatic balloon is used to dilate stenosis (anastomotic stenosis) below the leak/fistula, reducing the internal pressure of the organ and allowing better flow of secretions into the lumen.	Acute and chronic leaks and fistulas	Location/distance from the entrance orifice: anywhere in the GI tract. The indication for AB is just after sleeve gastrectomy. For strictures the hydrostatic balloon is the best option. Size: N/A Margin: N/A Tissue quality: healthy. Unhealthy tissue has a higher risk of perforation.	Easily to perform	Risk of perforation