I'm very happy to introduce our next speaker, who was my wonderful co-fellow, Dr. Ali Shuman. Dr. Shuman is the Director of Bariatric Endoscopy and Assistant Professor of Medicine at University of Michigan. Today, Dr. Shuman is going to be talking about endoscopic management of complications after bariatric surgery. Dr. Shuman, thank you very much for joining us. Thank you very much, Dr. Girapino, and thank you so much for the organizers of this event. It's such an honor to be here today and presenting. I know these slides have probably become redundant with all the presentations you've seen, but I do think the trends in the United States are important. As you can see, there is clearly an increase in the percentage of patients with obesity over the past several decades. With this comes an increase in the percentage of obesity-related comorbidities as well. This was a graph that our prior presenter similarly showed, and this is the prevalence of self-reported obesity among U.S. adults by state. All states, I think this is an incredible graph because it shows from the CDC that all states have more than 20% of adults with obesity. We know that the most effective treatment is bariatric surgery, but we also know that these procedures are the most invasive and they do not come without a potential risk of adverse events. Today, we're going to be reviewing the bariatric surgical procedures. We'll discuss recent trends and what is more or less common in regard to those procedures. We'll also talk about common surgical complications or adverse events, and then the endoscopic and medical management of each. Starting with a review of what bariatric surgical procedures are offered. Many of us are familiar that there's really four commonly performed bariatric surgical procedures. Over the last decade, we see a resurgence of both gastric bypass and also sleeve gastrectomy. We're going to focus mostly on those, and the reason is as follows. This is data from the Michigan Bariatric Surgical Collaborative, but it very much mirrors what's happening nationwide, which is for several decades, Roux-en-Y gastric bypass was the most commonly performed bariatric surgical intervention. Over the last decade or so, we've seen that the prevalence of sleeve gastrectomy has gone way up. With just a short amount of time to discuss the adverse events and complications that you may see in your practice, I figured I would focus most of this talk on the complications that we see following gastric bypass and following sleeve gastrectomy because of these numbers. Starting with gastric bypass, in order to understand what adverse events we see, it is important to delve a little bit into Roux-en-Y gastric bypass anatomy. As you can see here, a small gastric pouch, usually about 30 to 50 milliliters in volume or three to five centimeters in length, is partitioned from the larger gastric remnant, also known as the excluded stomach. And then an area of small bowel of jejunum is brought up and re-anastomosed to the gastric pouch at a site known as the gastrojejunal anastomosis. And this is important because many of the adverse events that we see following bariatric surgery occur at this anastomosis. So we're going to quickly review the ones that are probably most commonly seen by gastroenterologists and endoscopists. And we will start with marginal ulceration. So marginal ulceration is an ulcer at the gastrojejunal anastomosis that commonly occurs on the jejunal aspect of this anastomosis. And most of the data to date suggests that this occurs in approximately 16% of patients. However, we think the incidence might be as high as 50% because many patients are asymptomatic with this ulceration. When symptoms do occur, they commonly present as epigastric pain, obstruction, or less commonly GI bleeding. What is the etiology of marginal ulceration? So several of the etiologies are seen in normal peptic ulcer disease, which include things like acidity. So we know that that place plays a major role in the pathogenesis of a marginal ulceration. We also know that the gastrojejunal anastomosis is particularly at risk because of poor local tissue perfusion that can occur following surgical intervention. Smoking is one of the single biggest predictors of marginal ulceration. And some studies have reported that diabetes may also play a role. Medications such as NSAIDs or steroids, which can play a role in normal peptic ulcer disease, are also common etiologies of these procedures. And similarly, surgical technique can play a role. We also think H. pylori may play a role from some of the work that we have done, although several studies have been a little bit discontinuous with regard to whether this is a clear independent risk factor for a marginal ulceration. And finally, we know that foreign material, which is not uncommon following Roux-en-Y gastric bypass, may play a major role as it can sort of serve as an inciter for the development of a marginal ulcer. And here you can see what that looks like in a patient who we scoped several years ago. And typically, when I see this suture material, I'm usually removing it, especially if the patient has a history of ulcer disease. And you can do that with either biopsy forceps or with loop cutters or endoscopic scissors. So what is the treatment for marginal ulceration? So the mainstay of treatment is similar to the mainstay of treatment for peptic ulcer disease in a non-gastric bypass patient, which include high-dose proton pump inhibitors. And we showed in a study in CGH in 2017 that you really want to be prescribing these for the gastric bypass population in either a soluble or an open capsule form. Because as you can see from that graph to the right, patients who received it in a soluble or open capsule form as compared to a tablet form healed their marginal ulceration on the order of over 400 days quicker than those who took it in a tablet form. Some studies have also supported the addition of sucrophate solution. And you can prescribe this up to four times a day, which I usually save for refractory ulcers. Furthermore, it is imperative that patients stop smoking, that they discontinue their NSAIDs, that you remove any foreign material that may be a nidus for precipitating an ulcer like you saw in that past video. We typically send an H. pylori serology if they are treatment naive or a stool study if they've been tested and treated for H. pylori in the past, because usually pouch biopsies will have low sensitivity for detection since the majority of H. pylori may remain in the remnant stomach, which is obviously excluded during a normal operandoscopy. And then finally, when there's ulcerations that are truly refractory to medical therapy, you can consider endoscopic suturing or even surgery as a last resort. And next, we're going to move on to stenosis of the gastrointestinal anastomosis. And really, there's no precise definition for what constitutes stenosis. However, we typically say when patients are symptomatic and or the upper endoscope cannot pass through the gastrojejunal anastomosis. And the mainstay of treatment for this is really endoscopic balloon dilation. However, it's exceedingly important to remember that the gastrojejunal anastomosis is an end-to-side anastomosis. And so you can't really very easily blindly pass an endoscopic through the scope balloon through the anastomosis. You always have to be worried that you could be perforating the jejunal wall. And so there's many techniques for getting around this, including using an ultraslim scope to deliver a wire through the roux limb and making sure that you're not hitting the blind limb. And then passing an endoscopic through the scope balloon through that wire after backloading it into a normal scope. You can also use fluoroscopy or you can, if you don't have resistance, you can use a long flexible guide wire like an ERCP guide wire and pass it through a normal scope, making sure that whoever's passing that wire is not feeling resistance against the jejunal wall. And the true goal is really symptom improvement. You typically do not want to dilate past 15 millimeters as you can predispose the patient to weight regain. And on the upper left, you can see a classic picture of what it looks like when you have a tight stricture at the gastrojejunal anastomosis. On the bottom left, you can see this nice ring of ischemia while you're dilating through the scope balloon. And for refractory strictures, sometimes we're placing these lumen-opposing metal stents that are FDA approved for cis-gastrostomy, but they can be placed intraluminally and left for several months with about 50% of patients feeling much better even once the stent is removed. Next, I'm just going to quickly touch on dilation of the gastrojejunal anastomosis, but I believe our next presenter, Dr. Kambari, will be covering this in great detail. So I'm just going to quickly mention that we know that a certain percentage of patients never achieve the weight loss that they want to following a gastric bypass, or even that they do, a large percentage of patients will regain a certain percentage of the weight that was lost. And so we also know based on some studies done in 2011 and published in Gastroenterology that dilation of the gastrojejunal anastomosis has a linear relationship with weight recidivism. And as a result of this, several endoscopic techniques have been described for reducing the size of the gastrojejunal anastomosis. The one that has gained probably the most excitement is endoscopic suturing, and I'm sure you'll be hearing all about that from Dr. Kambari, so I'm going to glaze over this now. Next, I'm going to briefly discuss gastro-gastric fistula, and these are connections that occur between the gastric pouch and to the gastric remnant. And you can see here, if they are large, they have the potential to sort of reconstitute normal anatomy, as if the patient never had their gastric bypass. And symptoms, therefore, would include things like weight regain. However, other patients also experience pain from acid from the remnant stomach coming up through the gastro-gastric fistula and irritating the pouch or causing ulcers in the pouch, in addition to reflux and nausea and, less commonly, vomiting and other symptoms. Typically, these are diagnosed by upper endoscopy or upper gastrointestinal series. Cross-sectional imaging can also play a role. However, there's a higher false positive rate. The treatment for these is really high-dose PPI. And then if the patient is symptomatic with any of the above symptoms that I mentioned, then we really discuss endoscopic closure. And for fistula that are less than a centimeter in size, typically, endoscopic closure, usually using endoscopic suturing or even over-the-scope clips for people who don't have endoscopic suturing available, can be quite effective. However, when the fistula is much larger, including those that are over a centimeter and certainly over two centimeters, you really want to consider therapy on the remnant stomach if the patient has mostly complained of weight regain. And so you can perform many of the procedures that we've heard about through Dr. Thompson and other talks on the remnant stomach to try to facilitate weight loss. And here's just a quick video of what these fistula can look like. This was the patient who I scoped who actually had two large fistula. And you can see the most proximal fistula easily accommodates my scope. And here I am in the remnant stomach. And then when you come out back into the gastric pouch, you see that the true anastomosis, the gastrointestinal anastomosis is very distal, but yet there's a second endoscopic or gastro-gastric fistula just proximal that you can see endoscopically. Next, I'm briefly going to mention surgical leaks. We'll touch on this much more when we get to sleeve gastrectomy. But the important thing for gastric bypass patients is to understand that leaks can really occur at any point along any staple line. And typically the location and chronicity will dictate whether or not endoscopic management should be attempted and is feasible. But as we'll talk about in the sleeve leak section, you always want to be treating downstream obstruction because otherwise the pressure gradient in the system will not really allow for the leak to heal. Finally, I'm going to briefly mention colodocal lethiasis. So we know that gallstone disease is very common after Roux-en-Y gastric bypass and oftentimes associated with rapid weight loss. We also know that ERCP is very arduous in this patient population because you would have to, the traditional method of doing balloon-assisted enteroscopy required the proceduralist to go down the esophagus, through the gastric pouch, through the gastrojejunal anastomosis, down the Roux limb. And then eventually when you get to the JJ or jejuno-jejunal anastomosis, it would require that the proceduralist find the biliopancreatic limb and make sure that they're not going down the common channel, which as many of us know, you could do for hours without knowing. And then eventually you hit, if you have chosen the correct limb, you'll find the papilla or the ampulla. And the biggest problem is that once you get there, then you have to do an ERCP with very equipment that's clearly not designed for this anatomy. And so there are a whole slew of other techniques that have been discussed and reviewed and described by many interventionalists. Probably the one that has gained the most headway is EUS-directed transgastric ERCP or the EDGE procedure. And so just to briefly describe what this is, this is where we are placing a, we're locating the remnant stomach under endoscopic ultrasound, and then we're filling it with approximately a liter of fluid. And I'll show you in a video what this looks like in a minute. And then we are placing these luminoposing metal stents between the gastric pouch and the gastric remnant that allow us to facilitate scope access into the duodenum. And these can be, these are technically quite, in theory, quite challenging. And so there's many steps that you just have to think through before you set out to proceed one of these. And I'll go over that in a minute. I just want to show you what this looks like. So this is a gastrodegenal anastomosis. This is what the remnant stomach looks like under endoscopic ultrasound. And you can see in the upper right-hand corner, a FNA needle, a 19 gauge accessing the remnant stomach. And then we fill the remnant stomach with somewhere between 500 cc and a liter of fluid mixed with contrast in preparation for stent placement. And here you can see what the remnant stomach looks like on fluoroscopy. Then you pass the luminoposing metal stent catheter into the remnant stomach. You can deliver the distal end of the stent under endoscopic ultrasound guidance. And then you sort of back away and deliver the proximal end of the stent under endoscopic guidance, which you'll see in just a minute. And then at this point, you can dilate the stent open and you can pass your scope through the stent and ultimately perform an ERCP. And as I mentioned before, there's many things that we think through before we do these procedures, including the size of the stent. These stents come in 10, 15, and 20 millimeters. And depending on the size that you have available to you may dictate whether you can drive through the same day or you should wait for the fistula tract that you created to mature. Some people use a wire to make sure that you have good access to the remnant stomach in case you lose that access at some point. Some people feel that it torques them the wrong direction. And then the question is, do you have best access to the remnant stomach through creation of a gastrogastric fistula or did you create a jejunogastric fistula like you saw in that video? And that may have implications for whether you can do the ERCP the same day. Additionally, you want to think about whether or not you're going to fix the stent in some way so that you prevent migration of the stent as you're doing the edge procedure. And then again, as I mentioned before, whether you're going to drive through or wait for epithelialization. And then there's more thought that goes into these because you have to think about when you want to remove the stent, whether you want to leave a little plastic pigtail behind, what type of closure you're going to offer and whether or not you're going to confirm successful closure. So moving on to complications following sleeve gastrectomy. So sleeve gastrectomy is a procedure that we've heard a lot about today, which basically includes the removal of the greater curvature of the stomach. It's a very straightforward procedure surgically, but there are risks involved. The two that I'm going to spend the most time on are sleeve stenosis and sleeve leaks, mostly because reflux and Barrett's esophagus is not really specific to this procedure. And Dr. Kumbhari will likely mention weight regain. So starting with sleeve stenosis. So the incidence of sleeve stenosis is up to 4%. And patients typically present with nausea, vomiting, dysphagia. They can present with weight loss, regurgitation, and reflux. And we think there's really two types of strictures. There's early, which occur within the first four weeks of surgery and usually just represent edema or hematomas from the procedure. And then there's late leaks, sorry, strictures that occur over four weeks after the procedure. And we think these are the ones that are really the true strictures. And they can be due to ischemia or scarring or misalignment or rotation during stapling or the use of a small bougie. So here you can see sort of a cartoon illustration of what sleeve stenosis looks like. The majority of them occur about two thirds down the stomach at the incisora. And you can see what that looks like endoscopically at the top. And then commonly we see pooling of bilious fluid below it. And the question is really, how do you diagnose a sleeve stricture? And our group has done a decent amount of work trying to figure this out. And there's really no clear descriptive criteria. We recently published a study showing that upper GI series has a high positive predictive value, but a very low negative predictive value. And we more recently have been exploring the use of endoflip to help us determine whether or not patients are responding and really what normal values are. The treatment of sleeve stenosis is somewhat controversial, but the management strategies typically include endoscopic balloon dilation, self-expanding metal stents, or tunneled strictural plasty, or if everything else fails, potential conversion to a gastric bypass. And so typically we're using this algorithm well described by Dr. Thompson's group in Boston, which includes the use of a hydrostatic or through the scope balloon followed by a pneumatic balloon. And the way that he has described these is to start with a 30 millimeter pneumatic balloon and attempt to attain a pressure of 20 PSI, which is the max pressure you can put into the balloon. And then depending on the resistance, if you are unable to reach that max pressure, you may want to consider the same balloon size, but try to reach that max pressure in two to four weeks if the patient is still symptomatic. Otherwise, you can increase the balloon size by five millimeters and again, try to reach the max pressure. And success is quite high for these. They do come with the potential risk of bleeding and or perforation, which we think is somewhere around 3%. But just to show you what this looks like endoscopically, this is a very tight sleeve stricture that we found. And here you can see us sort of requiring quite a bit of torque and maneuverability of our upper endoscope to pass through it. And then you can see in a minute that we're going to be passing through the pylorus and then passing a very stiff guide wire through and delivering it distal in the duodenum, and then eventually delivering the pneumatic balloon over that guide wire. And here you can see the pneumatic balloon has been centered right at the level of the stricture and you can see a nice ring of ischemia as we dilate the balloon. And as I mentioned before, these do not come without risk. And here's a case where you could see this ascending appearance of ischemia. And at this point, the patient had already been dilated once. We had only gone up to about 12 PSI, but you can already see that this does not look normal. And so we immediately deflated the balloon, but unfortunately you can see this large sort of 3 by 5 centimeter gaping defect on the lesser curvature of the stomach. And so this patient was hemodynamically stable. And so we were able to endoscopically fix this or close this without the patient requiring operative intervention. And so here you can see that we've loaded the endoscopic suturing device that you've heard a lot about throughout the course of the day. And you can see that we're going to be suturing from distal to proximal and closing this defect. And for the sake of time, I'm not going to show you this whole video, but let me see if I can scroll through and just show you sort of at the end. We are placing some interrupted stitches over the running stitch that we just placed. And then eventually, you can see that the defect is entirely closed. And we admitted this patient in an upper GI series following the procedure confirmed no residual leak. Self-expanding metal stents, as I mentioned, also play a role potentially in resistant cases, but they have a very high risk of migration. So we always recommend fixating the proximal side. Endoscopic tunneling strictuloplasty also may play a role, and it may be ideal. This is what had been described, again, by Dr. Thompson and Dr. Giropinio's group in Boston. It may be ideal if the length of the stricture, the length of the sleeve, prohibit pneumatic dilation, or in patients who really don't require multiple sessions or don't desire multiple sessions. And here you can see some pictures of what those look like, but very similar technique to performing a G-POM or a Z-POM. And so I like this algorithm that was published in 2017, just thinking about how you sort of approach patients with strictures. You could potentially do a barium swallow or an upper endoscopy to confirm it. And then you think about pneumatic dilation, and typically that occurs over the course of several sessions. Some people will elect to place covered metal stents, but it's important to consider fixating those, so they don't migrate and then ultimately progress to some of the more aggressive techniques. Next I'm going to briefly discuss sleeve leaks. So these are clearly the most feared adverse event. They present with tachycardia, leukocytosis. They can present as fulminant sepsis or peritonitis, commonly elevating CRP on lab work. And they usually occur when the intragastric pressure is exceeding the burst pressure, which again can be precipitated by these distal sleeve strictures. And typically they occur just below the angle of HISS along the proximal staple line, because this is a relative area of ischemia and also a zone of increased pressure. And really the type of leak, how large the leak is, and whether or not there's accompanying abscesses or fistulas dictate how you can endoscopically manage these. So timing and chronicity are very important as well. Those that are acute or early may be managed totally differently from those that are late or chronic. And as I mentioned before, the size plays a role. And we have quite a large endoscopic armamentarium that I'll touch on briefly in the following slides. But as I mentioned before, dilation distal to the leak is imperative for treatment and management. So covered metal stents are ideally used in early or acute leaks, and they really, you should try to span these from the distal esophagus to the duodenal bulb and even consider overlapping them to achieve appropriate extension or coaptation. And this allows for anterograde flow of secretions. And again, you want to think about fixating these in the esophagus to prevent migration. Stents specifically designed for bariatric use, like you can see in this picture, are not yet fully available in the US, but I think we're moving in that direction. So here's an example of a patient who had had a lap band and then converted to a sleeve. And so she developed this large leak. You can see the tight stricture at the bottom. We placed a covered metal stent, and here you can see it in the top of the esophagus, and then we sutured it to the proximal esophagus. And usually reported success rates can be as high as 80%, but they're very high migration rates. And what we know from the largest multicenter retrospective study is that the probability of successful closure with these stents really decreases with leak chronicity. And so the earlier, the better when you're thinking about placing a covered metal stent. And furthermore, with migration, you can have quite serious adverse events like perforation or death. Next, I'm going to briefly mention the use of pigtail stents. So these are ideally used in later leaks or used to be thought to be most effective in later leaks. Now there's sort of a push to think that maybe we could do these earlier as well. But these allow for facilitation of drainage from the cavity into the gastric lumen using a technique very similar to necrosectomy. And this has very high technical success, seems to require fewer procedures and lower morbidity. And you can see those success rates there, almost 100% technical success. So I just want to show you what this looks like. This is a leak that was seen just below the angle of hiss in the common place that I mentioned before. You can see pus exuding through it. Here you can see dilation with a hydrostatic balloon distal to the sleeve, and then with a pneumatic balloon at the level of the incisora. And then you can see as we're coming up, you can again see the leak site. And what we do is explore the cavity with an ultra slim scope. And you can sort of clean out the cavity. In this case, it was found that this patient had a lot of food debris and gum in the cavity that was removed. And then ultimately, you can see placement of these sort of a clean cavity and then placement of these small plastic pigtail stents that become transgastric. And in a minute, you'll see what these look like as well on fluoroscopic evaluation. And then septotomy is a technique I've been doing a lot more of for late or chronic leaks with really good results, but it really requires a fibrotic septum and a contained leak cavity. And so typically what you're doing is separating the cavity from the gastric lumen and exposing the cavity to fully equalize pressures and provide healing. And there's a whole slew of different instruments that have been described for how these are performed. I was going to show you a quick video of one that we did more recently. This is a large collection. You can see that had already been evacuated or attempted evacuation with these JP drains that have been placed surgically. Here you can see the upper GI series with a massive leak that's visualized. You can see clearly on screen right. Then we performed an upper endoscopy. And what you can see in just a minute is this leak site that's filled with really thick material. And so we had some concerns about the consideration of placing a covered metal stent and sort of walling this off. Instead, what we elected to do first was place some plastic pigtail stents. We also dilated distally and you'll see in a minute, we eventually place a covered metal stent. And then finally, once the leak is a much more chronic, you can see that we're coming down endoscopically and we're in a minute, I'll show you there's the septum and the cavity is just above the septum and then sort of screen right where you see my scope passing through now is the true gastric lumen. And so what we did was we used these sort of cautery scissors and you can see in just a minute how we divide the septum. And it's very important to divide all the way to the bottom of the septum. And using this technique, we were able to do all of this in a single procedure. So we were able to divide about three to five centimeters of length of the septum in a single procedure. Traditionally, people have described using either APC or needle knives and really only being able to do about half a centimeter or one centimeter at a time. But we had good success with this particular instrument. And here you can see that we do also use APC as adjunctive therapy and we're removing foreign material as we go down to really promote effective closure. And so in a minute, you'll see what it looks like when we get to the bottom of the cavity. You can see that we're going back to this cutting insulated cutting knife and really making sure that we're hitting the very, very distal end of this cavity. And then eventually, once it's all cleaned out and you've sort of equalized the pressure between the lumens, you are done with the procedure. And this patient did quite well. This is imaging following that showed complete resolution of the leak. And we've seen her now about two years later. She's doing great. There's a whole slew of other devices and options in our endoscopic armamentarium that I'll spend little time on. But just to say this is a complex procedure. And you have time to sort of, you know, if you have the time and expertise at your center, you should really try multimodal therapy. So in conclusion, bariatric surgery is effective with the prevalence clearly of sleeve gastrectomy rapidly rising. And as a result, the adverse events that we see with that are coming with higher prevalence. Despite improvement in the performance of these procedures, adverse events and complications are not uncommon. And so endoscopists should be familiar with anatomy and complication management strategies. But these, of course, should always be performed in the context of a comprehensive multidisciplinary center. Thank you very much. Thank you.

bariatric surgery

complications

endoscopic management

gastric bypass

sleeve gastrectomy

multidisciplinary approach