Food impaction may occur after RYGB; it may be associated with the use of surgically implanted restrictive ring due to ring slippage or erosion , dietary noncompliance , gastric pouch , or gastrojejunostomy stenosis . Clinical presentation is consistent with upper gastrointestinal obstruction, involving nausea, retrosternal pain, epigastric discomfort, and postprandial vomiting. Endoscopy can be used for diagnosis and immediate treatment.

An endoscopic retrieval basket is the most commonly used accessory for foreign body removal. When it is difficult to remove all of the fragments orally, retained fragments can be gently pushed into the distal jejunal loop, passing the restriction point . It is advised to use minimal sedation during the procedure, due to a potentially increased risk of aspiration of gastric contents. This risk can be prevented by undertaking the procedure under general anesthesia after endotracheal intubation with or without the use of an overtube. The overtube is a device through which the endoscope is passed, protecting the cardia, esophagus, and airways during foreign body removal [4, 5]. It is also strongly advised that after resolution of symptoms , the etiology of the narrowing is investigated and resolved.

Marginal ulcers may occur either early or late in the postoperative period of RYGB . This complication’s etiology is still not completely understood, and there is no established treatment protocol [6, 7]. It can be found in 27–36 % of symptomatic patients; interestingly, it is also incidentally detected in up to 6 % of asymptomatic patients after surgery [8].

When appearing as an early postoperative complication , it is thought to be associated with the surgery itself. In the late phase it may be secondary to the existence of a large or long gastric pouch (greater number of parietal cells) or presence of nonabsorbable sutures or staples [9]. The development of a marginal or anastomotic ulcer after RYGB may be explained by the preservation of the antrum and the vagus nerve, causing hypergastrinemia and increased gastric acid production. They are often located in the jejunal mucosa just below the gastrojejunal anastomosis and may involve the entire circumference of the small bowel [6] (Fig. 7.2).

Presentation includes epigastric pain and obstructive symptoms caused by edema . Upper GI endoscopy is the investigation of choice; findings include injury to the gastrojejunal anastomosis , varying in size and depth, commonly on the lesser gastric curvature side of the pouch and with a fibrin-covered ulcer base.

Prophylaxis with acid suppression after surgery is increasingly being used with the aim to prevent marginal ulcer formation. However, no consensus exists about the duration of the prophylaxis, usually varying from 30 days to 2 years, with some recommending lifelong usage [10]. Treatment of marginal ulcers should include high-dose PPI therapy (for at least 2 months) and sucralfate (10 days). Upper GI endoscopy should be repeated to ensure healing .

The incidence of gallstone disease is increased after RYGB . Management of choledocolithiasis in these patients can be challenging due to difficulty in access of the common bile duct (CBD) , as a result of surgically altered anatomy of the stomach and duodenum [11]. A combination of laparoscopy and endoscopy can be used to perform a transgastric endoscopic retrograde cholangiopancreatography (ERCP) , along with laparoscopic cholecystectomy . Access can be done by a 1 cm incision in the anterior wall of the remnant stomach through which a duodenoscope (introduced laparoscopically) is passed. The procedure is then performed as a conventional ERCP [12].

In the cases where this is technically difficult, an alternate technique reaches access to CBD via jejunum, facilitated by a double-balloon enteroscope . This approach has a successful biliary cannulation rate of up to 60 % [13].

With evolution and modifications of standard bariatric procedures , the use of a band or silastic ring implanted around the gastric pouch at the time of RYGB was widely accepted. This technique presents a new array of complications, the most significant among them is gastric erosion . The incidence of intragastric ring erosion varies from 0.9 to 7 %, occurring slowly with an inflammatory capsule formation. This inflammation prevents the leakage of gastric contents into the abdomen, leading to a nonspecific clinical presentation, with up to 15 % of the patients asymptomatic. When symptoms do occur, they include weight regain, epigastric pain , and obstructive symptoms, and sometimes even upper gastrointestinal bleeding [14].

At diagnostic endoscopy, the eroding prosthesis is often seen directly in the lumen of the gastric pouch . An early endoscopic finding may be an ulcer at the site of ring erosion; these patients should be started on high-dose PPIs, with evidence suggesting that migration of the ring is found in more than 50 % of such patients [15].

The eroded ring can be removed with a standard one-channel endoscope, utilizing endoscopic scissors [16]. In cases of failure due to the rigidity of the ring, an endoscopic lithotripter (or gastric band cutter ) can be used.

In cases of early migration, if the ring has only a small area of intragastric erosion and is adherent to the gastric pouch wall, a dual-channel device can also be used. This allows the introduction of a foreign body-grasping forceps for traction , for better ring exposure . The other channel can then be utilized to pass an argon ablation catheter to divide the ring, or even scissors.

Postprandial vomiting, dysphagia , and other obstructive symptoms should always be investigated in bariatric patients, specially when a ring was used. Ring slippage corresponds to distal displacement of the prosthesis, subsequently causing obstructive symptoms. In cases of complete slippage, there can be signs of esophagitis from excessive vomiting, gastric pouch dilatation , or formation of a gastric “neofundus ” [17]. Food residues can also be seen in the gastric pouch and a site of stenosis is seen in the jejunal folds distal to the anastomosis .

Some patients may have frequent episodes of vomiting with no evidence of stenosis, a condition quoted by the authors as “food intolerance secondary to the presence of the ring” [18].

Dilation with a 30 mm balloon (Rigiflex^® —Boston Scientific, Natick, MA) promotes stretching or rupture of the ring and the fibrotic bands caused by its presence, which can relieve symptoms, even in the patients diagnosed with food intolerance and no stenosis. If symptoms persist, a self-expanding plastic stent can be used, promoting intragastric ring erosion and allowing a completely endoscopic removal with minimal complications [17, 19].

Some patients who undergo RYGB may regain lost excess weight; around 20–30 % regain a large proportion of their lost weight, leading to a negative impact on quality of life [20]. Several factors may be related to regain, such as poor nutrition , fistula, surgical technique, and ring complications, among others. It is important to evaluate dietary and behavioral habits in cases of inadequate weight loss , such as volume quality of the meal and anxiety disorders.

Dilation of the gastrojejunal anastomosis and gastric pouch enlargement are possible causes of RYGB failure. In the presence of a dilated stoma, the most traditional approach is surgical. Even if reoperation is done laparoscopically, it is still complex and associated with significant morbidity and questionable efficacy. Development of endoluminal therapies for pouch and stoma revision can be a less invasive approach for failure or weight regain after bariatric surgery.

A multidisciplinary team evaluation, as well as endoscopic or radiologic imaging of the surgical anatomy, should be done in cases of weight regain in the late postoperative period. An increase of 10 mm on the stoma diameter was associated with an 8 % increase in the percent of maximal weight lost after RYGB that was regained [21]. The ideal anastomosis should have an approximate diameter of 10 mm, not exceeding 14 mm.

Application of argon plasma has been reported as a way to induce the formation of a fibrotic scar and consequent anastomotic diameter reduction [22, 23]. To produce the desired effect, the anastomosis should be coagulated in a circumferential way. There is an initial edema and inflammatory response, causing immediate restriction. This effect decreases over time, and the edema is substituted by fibrosis. More than one session is necessary in order to achieve long-lasting effects [24]. This leads to a delayed gastric emptying, early satiety, and weight loss.

Endoscopic suturing devices , such as the Apollo OverStitch^® (Apollo EndoSurgery, Austin, Texas), have been presented as minimally invasive alternatives, and may be used alone or in association with argon plasma coagulation. The procedure involves suturing the internal mucosa , thereby restricting the gastric lumen. The sutures are performed under direct vision , with the aid of a curved needle [25].

This is one of the most feared complications after bariatric surgery and may present with variable symptoms according to the site of the fistula [26, 27].