Role of endoscopy in bariatric surgery patients

Obesity is an increasingly serious health problem and represents an important risk factor for several gastrointestinal diseases, such as gastroesophageal reflux disease, erosive esophagitis, hiatal hernia, Barrett’s esophagus, esophageal adenocarcinoma, Helicobacter pylori infection, colorectal polyps and cancer, non-alcoholic fatty liver disease, cirrhosis, and hepatocellular carcinoma. Surgery is the most effective treatment for BMI>35KG/M2 to date, resulting in sustainable and significant weight loss, along with the resolution of metabolic comorbidities in up to 80 percent of cases. Many of these conditions can be clinically relevant, and have a significant impact on patients undergoing bariatric surgery. There is evidence that the chosen procedure might be changed if specific pathological upper gastrointestinal findings are detected preoperatively. The value of a routine endoscopy before bariatric surgery in asymptomatic patients (screening esophagogastroduodenoscopy) remains controversial. The common indications for endoscopy in the postoperative bariatric patients include the evaluation of symptoms, the management of complications, and the evaluation of weight loss failure. It is of critical importance for the endoscopist to be familiar with the postoperative anatomy. The purpose of this article is to review the role of the endoscopist in a multidisciplinary obesity center as it pertains to the preoperative and postoperative management of bariatric surgery patients.

Preoperative endoscopy
The value of a routine endoscopy before bariatric surgery in asymptomatic patients (screening EGDS) remains controversial. A lack of correlation between patient symptoms and endoscopic findings has been documented by many authors, suggesting that routine preoperative endoscopy might be useful in detecting both lesions and inflammation. However, considering the relatively weak clinical relevance of the majority of lesions discovered on routine EGDS and the cost and invasiveness of the procedure, as well as the amount of secondary unnecessary workup prompted by irrelevant findings, several authors have instead advocated a non-endoscopic approach for asymptomatic patients.

One of the concerns of performing routine preoperative upper endoscopy is the risk of sedation. It is of paramount importance that endoscopy procedures in obese patients are carried out in a fully equipped setting and by a well-organized team of anesthetists.

Postoperative endoscopic management
Several surgical procedures are currently performed to induce weight loss in obese patients. These procedures have been simplified into three categories – predominantly restrictive procedures, predominantly malabsorptive procedures, and combined procedures.

The common indications for endoscopy in postoperative bariatric patients include the evaluation of symptoms, the management of complications, and the evaluation of weight loss failure.

Of critical importance is for the endoscopist to be familiar with the postoperative anatomy and work in close collaboration with bariatric surgery colleagues.

Gastrointestinal complications prompting endoscopy after surgery may be summarized as follows: acute bleeding and/or anemia, staple-line complications, band stenosis, erosion and slippage, bezoars, and choledocholithiasis.

An endoscopy is the preferred strategy, unless there is a suspicion of leaks or fistulae, in which case preliminary contrast radiography may be more appropriate.

Role of endoscopy to diagnose and treat hemorrhage
Early upper hemorrhage (within 48 hours) are mostly reported after laparoscopic RYGB surgery (1 percent-4 percent). The bleeding lesions are often identified at the staple lines of the gastrojejunostomy and rarely at the jejunojejunostomy, gastric pouch, or bypassed stomach. Although there are few published case series, endoscopic management of hemorrhage from the gastrojejunal anastomosis has been shown to be highly successful when using standard hemostatic modalities. Late hemorrhage may often arise from marginal ulcers or erosion and generally requires medical therapy (PPIs) or, in cases of acute bleeding, endoscopic treatment. Balloon enteroscopy has been reported in patients with GI bleeding arising from the bypassed stomach, but should be undertaken only with great caution.

Role of endoscopy in treating staple-line complications
Endoscopic treatment plays an important role in the management of a variety of staple-line complications, such as stomal stenosis and anastomotic leaks.

Endoscopic dilation of stomal stenosis via through-the scope balloon dilation or wire-guided bougie dilation is safe and highly effective, and should be considered the primary treatment for this complication.

A potential risk of stricture dilation is inadvertent over-dilation, leading to weight regain. Overall, it appears that stricture dilation to a maximum of 15 mm is not associated with impaired postoperative weight loss outcomes.

Staple-line dehiscence, or leak formation
Staple-line dehiscence, or leak formation can lead to abdominal pain, thoracic pain nausea, vomiting, intra-abdominal abscess, and acute peritonitis.

Leak rates vary by type of surgical intervention, with large series reporting 2.05 percent to 5.20 percent for laparoscopic RYGB, and 1.68 percent to 2.60 percent for open RYGB. Sleeve gastrectomy has an associated leak rate of 0.6 percent to 7 percent.

The most common sites for RYGB leaks are at the gastrojejunal anastomosis, followed by the jejunojejunostomy anastomosis; in sleeve gastrectomy, leaks usually occur at the proximal border within 2 cm of the angle of His.

The first step is the treatment of sepsis and supportive care, including total parenteral nutrition and transcutaneous drainage catheter placement. Some leaks may resolve with these conservative steps. For stable patients, in whom conservative management has failed, laparoscopic repair should be considered. Additionally, in these patients, endoscopy is emerging as an effective procedure in the treatment of anastomotic leakage, while avoiding invasive surgical reoperation.

Chronic leaks have been successfully repaired endoscopically by using fibrin-glue injection, clip placement, self-expanding stents, and endoscopic suturing device.

Although endoscopic therapy for gastric leak management holds promise, these procedures cannot be routinely recommended due to the lack of controlled data.

Role of endoscopy to diagnose and treat laparoscopic adjustable gastric banding complications
The laparoscopic adjustable gastric band (LAGB) is well-established as a safe, effective, and durable bariatric procedure.

LAGB erosions typically occur 1–2 years after placement. The prevalence varies in published studies from 0.9 percent to 3.8 percent. Gastric band erosion may occur with abdominal pain, nausea, vomiting, abdominal access port-site infection, increased food intake, or weight gain, and is easily identified with endoscopy. The traditional approach is surgical revision; however, there are reports of conservative management with endoscopic removal on complete intragastric erosion.

Role of endoscopy to treat choledocholithiasis in patients with gastric bypass
Morbid obesity is a risk factor for gallstone formation, and rapid weight loss is an independent and potentially compounding risk factor.

Whereas an endoscopic retrograde cholangiopancreatography (ERCP) can usually be performed after gastric banding or sleeve gastrectomy, an ERCP in a patient with an RYGB presents significant technical challenges.

Several options are available to gain access to the biliary tree in patients after RYGB. Laparoscopic creation of a point of access to the gastric remnant or small bowel allows the duodenoscope to reach the papilla, but carries the inherent risks of general anesthesia and surgery. Enteroscopes, colonoscopes, and more recent double-balloon and single-balloon endoscopes have also been used. However, duct cannulation is difficult with the forward-viewing enteroscope, and precut biliary sphincterotomy is often required. Furthermore, accessories are limited due to the length of the enteroscope.

Outlook
GI endoscopists play an integral role in the multidisciplinary treatment of obese patients undergoing bariatric surgery, particularly in the treatment of postoperative complications. Direct communication and coordination with the surgical team is critical in the preoperative and immediate postoperative setting. Endoscopy is emerging as an effective procedure in the treatment of bariatric surgery complications in selected patients, while avoiding invasive surgical reoperation.

The author’s affiliations include Director – Indian Institute for Metabolic Sciences, Jt Obesity Solutions, Jt Foundations; International Center of Excellence Bariatric Surgery; Ruby Hall Clinic, Poona Hospital, KEM Hospital, Pune; Dr. L.H Hiranandani Hospital, Mumbai. She has been ex Vice President, IAGES; Organizing Secretary, IFSO APC 2017; Past Secretary, OSSI; Fellow, Gastro Obeso Centre, Brazil; Cleveland Clinic, Ohio, USA; Past Governing Council Member, ASI; Vice President, Mah Chapter, AIAARO; International Committee Member, IFSO; Research Committee member, ASMBS and Convenor: Obesity Task Force, State Govt of Maharashtra.