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Novel Name—and Algorithm—Proposed for Endoscopy After Roux-en-Y Gastric Bypass

Key findings

  • Endoscopists have developed an algorithm for endoscopic retrograde cholangiopancreatography in patients who have undergone Roux-en-Y gastric bypass, which they call gastric access temporary for endoscopy (GATE)
  • GATE allows other endoscopic procedures of the foregut (e.g., endoscopic ultrasound, endoscopic submucosal dissection) to be performed with standard endoscopes and equipment in this patient population
  • In a series of 10 patients, GATE and subsequent endoscopic interventions were 100% successful, both technically and clinically

In line with the rising prevalence of obesity in the U.S., it's estimated that 40,000 to 65,000 Roux-en-Y gastric bypasses (RYGB) have been performed every year for the past decade. Among patients presenting with pancreaticobiliary disease, gastroenterologists can expect to see more who have RYGB anatomy.

Whether endoscopic retrograde cholangiopancreatography (ERCP) is device assisted or performed laparoscopically, it can be technically difficult in patients with RYGB anatomy. Recently, multiple case series have been published about a novel endoscopic technique for these patients, which involves using endoscopic ultrasound (EUS) to guide the placement of a fully covered, lumen-apposing metal stent (LAMS).

Using a LAMS, gastroenterologists can endoscopically create a temporary transgastric access tract, which facilitates advanced therapeutic endoscopy of the foregut, including traditional ERCP using a standard duodenoscope. This procedure has been called EUS-directed transgastric ERCP, EUS transgastric fistula and EUS-guided gastrogastrostomy-assisted ERCP.

To avoid confusion with surgically assisted transgastric ERCP, gastroenterologists at Massachusetts General Hospital are performing the new procedure under an alternative name: gastric access temporary for endoscopy (GATE). In Surgical Endoscopy, Thomas J. Wang, MD, a resident physician in the Department of Medicine at Mass General, and colleagues describe their technique in detail, report on their experience with 10 patients and offer tips that may improve outcomes.

Case Series

The 10 patients underwent GATE at Mass General and Brigham and Women's Hospital between May 2017 and March 2018. Nine were female and the average age was 60 (range, 53–71).The two advanced endoscopists who performed the GATE procedure developed a novel algorithmic approach that they used for selecting the access site and completing the procedure.

Technical Success of GATE

In all 10 cases reported, the LAMS was deployed successfully. The access tract was gastro-gastric in three patients and jejunal-gastric in seven. Within the latter group, the jejunal structure involved was the blind limb in four patients, the Roux limb in two and the saddle in one (the saddle is immediately distal to the gastrojejunostomy and bridges the blind and Roux limbs).

Clinical Success of Follow-up Procedures

In one patient, GATE was performed to facilitate endoscopic ultrasound followed by endoscopic submucosal dissection of a duodenal mass. The nine other GATE procedures were performed prior to ERCP.

In seven of those nine cases, ERCP was performed at the same time as GATE. For the other two cases, both access sites were from the blind jejunal limb, and there was concern that the tract was insufficiently mature to accommodate the duodenoscope safely. Neither patient required urgent intervention, so the tracts were allowed to mature for two to three weeks before ERCP.

All additional procedures were performed successfully. They required many diagnostic and therapeutic maneuvers that could not have been performed through an enteroscope, including a large sphincterotomy, aggressive stone extractions and placement of biliary self-expanding metal stents, in addition to the procedures for the patient with the duodenal mass.

Stent Exchange

Of the seven patients who had ERCPs performed at the initial visit, three had their LAMS immediately exchanged for a plastic double pigtail stent. Regarding the four other patients:

  • One had a suspected pancreatic malignancy, so the LAMS was purposely left in place to permit any additional ERCPs and to allow for additional caloric intake
  • In three patients with jejunal-gastric access sites, there was concern about immature tracts. For these patients, follow-up esophagogastroduodenoscopy was scheduled so the LAMS could be exchanged at a later date

Closure of Temporary Access Tract

Of the 10 GATE cases, one patient was lost to follow-up and two chose hospice care. All seven remaining patients had documented confirmation of access tract closure.

Notes for Endoscopists

These findings indicate the notable efficacy of GATE among patients with RYGB anatomy. However, researchers do report a series of important observations and procedural tips, such as:

  • Prioritize confirmation of site access closure, which is a significant risk inherent to the procedure
  • Pursue strategies to avoid LAMS dislodgment. These can include use of a thinner diagnostic duodenoscope vs. a therapeutic duodenoscope; use of a G-G access site, deferment of ERCP during the two-to-three week tract maturation time period if a J-G access site is used or the use of the 20 mm diameter AXIOS stent with 27 mm anchoring flanges to enhance safety of duodenoscope passage post-LAMS placement
  • Exchange LAMS for a double-pigtail stent after subsequent ERCPs are no longer expected

An accompanying video presents a virtual tour of a live case.

Interestingly, patients seem to understand the procedure better now that they're told the "GATE will be opened" to permit foregut endoscopic procedures, after which it will be closed.

Dr. Wang and his colleagues say GATE–ERCP should be trialed at centers that already have expertise with the LAMS and are able to closely monitor access tract closure.

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