Moving on with our endoscopy presentations, our next presenter is Dr. Aaron Shields, who joined Rockford Gastroenterology Associates in 2004 and currently serves as Managing Partner. He specializes in liver disease and disorders of the biliary system and the pancreas. At the University of Illinois College of Medicine at Rockford, Dr. Shields holds the title of Clinical Associate Professor of Medicine. Dr. Shields is a member of the ASGE Reimbursement Committee, and he previously served on the ASGE Health and Public Policy Committee. Aaron, the audience is yours. I'm very happy to be back, being able to talk with everybody today. I'd just like to point out that the growth of this has been fantastic. You know, we have more than 200 people signed up, and I see that 160 are watching it live, and it's just a great opportunity for those of us who work closely with both nurse practitioners and physician assistants to kind of help further the education. It's something that I think everybody involved just thinks it's a really, it's a high-priority thing and something that we all very much enjoy. So my topic is going to be on EUS and ERCP. I have no financial disclosures. So ERCP, endoscopic retrograde cholangiopancreatography, I can say it provides some of the highest moments in GI, such as when you pull a stone out of a patient's bile duct and they immediately feel better, and some of the lowest moments, such as when a patient develops post-procedure pancreatitis. It's a procedure that requires a healthy amount of respect, both for the number of things that you can accomplish with it, but also with the potential for negative patient outcomes. So my goal today is to try to give you just a good overview of ERCP and endoscopic ultrasound. I think it's important that advanced practice providers be able to know when to do these procedures, when not to do these procedures, and be able to explain to the patient exactly what the procedure involves. So we're going to cover most of that today. So this is a, ERCP is a technique that has been, it's been around since about the mid-80s. It's primarily used for the diagnosis and management of both pancreatic and biliary diseases. And there's been a pretty significant change in how we perform ERCP, or at least in the reasons that we perform it. Initially, it was largely a diagnostic procedure. But there are very few diagnostic ERCPs performed, and it has moved primarily to a therapeutic procedure. And the main reason for that is that there are other, much less risky procedures, which have essentially replaced diagnostic ERCP. And we're actually going to, actually going to talk about a lot of those during the, during my talk on imaging tomorrow. So ERCP is done with a specially modified upper endoscope. And I know Dr. Martin kind of reviewed some of the different types of scopes that we use for upper endoscopy. But essentially, the procedure is performed usually with the patient under either general anesthesia or MAC anesthesia, and typically in the prone position. For visualization purposes, that happens to be the best position. And then essentially, the endoscope is passed through the patient's mouth, through the esophagus and stomach, and down into the small intestine. And the main difference with this scope is that it's what's called a side-viewing scope, so that as you pass the endoscope down to the second portion of the duodenum, the major papilla lines up directly across from the scope, so that you get very nice visualization. And from there, you can advance your various devices through the scope and into either the pancreatic duct or the common bile duct, depending on what your objective is for that particular procedure. I think to kind of illustrate in a little more detail, I just, here's a nice schematic of how we would use ERCP to extract a stone. And so here's some of the important anatomy to just to review. Here's the duodenum, the minor papilla, the major papilla, and you can see that there's a stone impacted kind of right down at the bottom part of the bile duct, likely passed from the gallbladder, which obviously has a lot of other stones. And at the time of ERCP, what we're able to do is pass the endoscope down into the duodenum, and then pass a, usually what's called a sphincter tome or a catheter, which goes into the major papilla, and we can be guided to cannulate the bile duct. And then there are various interventions that can be performed. Typically, we're injecting dye there to better visualize. And so in this panel, you can see, this is the scope here. And then you can see that there's a device that's been inserted into the common bile duct, and the contrast has been injected. And you can see that there are these multiple filling defects kind of lined up throughout the bile duct. And so this would be kind of a classic image for somebody with a common bile duct stone. And then at the same time, not only can we diagnose the problem, but we're able to successfully remove these stones by first performing a sphincterotomy to open up the biliary sphincter, and then using either a balloon or a basket to retrieve the stones and basically pull them out into the intestine. So this is kind of one of the more common indications and a good schematic of just how an ERCP is performed. I think one of the things that I enjoy most when I'm working with my nurse practitioners is just trying to figure out whether somebody is a good candidate and whether ERCP is appropriate, or whether there are other more appropriate tests that can be performed. We've already talked about one of the most common indications, which is a patient who has a common bile duct stone, and that may be associated with cholangitis as well. Some of the other common indications for ERCP include patients who show in jaundiced with malignant biliary obstruction from things such as pancreatic cancer, cholangiocarcinoma, or bile duct cancer, or sometimes even a mass within the liver, which is obstructing the bile ducts. Post cholecystectomy bile leaks used to be a much bigger issue when surgeons first started doing laparoscopic cholecystectomy. It's less commonly seen now, but we still occasionally will see the patient who has a bile leak. Bile strictures, either after a cholecystectomy or related to a liver transplant or primary sclerosing cholangitis is another indication. Not all the work is done in the bile duct. Sometimes we need to work on the pancreatic duct as well, so patients with chronic pancreatitis who have either intraductal stones or a biliary stricture sometimes require ERCP. Finally, pancreatic duct injuries or leaks, which can occur either following abdominal trauma or sometimes a severe episode of pancreatitis. I would point out that what's not on this list is patients with chronic abdominal pain. As we'll talk about during my medical legal talk later today, doing ERCPs on patients with chronic abdominal pain is a good way to get yourself into trouble and unfortunately it's not something that we typically do anymore. I think this is one of the most important slides because this is such a common indication for ERCP. Patients obviously frequently present with abdominal pain and a suspicion for a common bile duct stone, oftentimes because they've had abnormal ultrasound or they've got liver tests which suggest that there may be a common bile duct stone. This slide is directly taken from the ASG guidelines and I make all my nurse practitioners learn this well because especially if you're in the inpatient setting, these particular questions come up quite often. If you have a patient who shows up with a suspected common bile duct stone, essentially what you want to do is you want to divide it and figure out whether they're high risk for a CBD stone or whether they're at a low risk. That's really going to dictate what your appropriate testing is going to be. If you have a patient who has a high risk for a common bile duct stone, and that would be anybody who has a directly visualized stone on either ultrasound CT or MRCP, somebody who has a bilirubin greater than four and a dilated common bile duct on imaging, or somebody with clear evidence of ascending cholangitis, in that situation you can proceed directly to ERCP. For patients who have a lower risk for a common bile duct stone, for example, the liver chemistries are elevated but the bilirubin is not at least four, if they just have a dilated duct on ultrasound or if they come in with acute biliary pancreatitis, those are considered lower risk for having a residual common bile duct stone, and in those cases you want to go for safer options. Typically MRCP, because it's readily available and doesn't require invasive procedures, oftentimes the next test done to determine if somebody truly has a common duct stone, and of course if they do, then you can proceed to ERCP. Other options include endoscopic ultrasound, which we're going to talk about in the second half, and then sometimes we'll just have these patients go directly to surgery for a laparoscopic cholecystectomy, and the surgeon can perform an intraoperative cholangiogram at the same time. So there are some important things to assess before scheduling your patient for ERCP, and these of course apply to other endoscopic procedures as well, but reviewing the preoperative risk assessment, including their ASA classification, make a decision on sedation plan, nowadays most ERCPs are done with either general anesthesia or occasionally with MAC. Antibiotics are really only indicated if a patient has primary sclerosing cholangitis, or if after you've done the procedure you haven't been able to drain an obstructed bile duct, then we'll sometimes give antibiotics, but it's certainly not routine to prescribe antibiotics. Rectal endomethacin is something that we give most every patient because it's been shown to decrease the risk of post-procedure pancreatitis in high-risk patients, so these are things that you want to be thinking about when you're seeing your patient prior to ERCP. I won't spend too much time on this because we've already touched on it during the anticoagulation lecture, but just to emphasize that sphincterotomy and dilation of the biliary sphincter are considered high-risk procedures, and in those cases you do want to hold the anticoagulation and the antiplatelet agents kind of per guidelines. There's really no consensus on what the INR is. I think most advanced endoscopists would say something less than 1.8 is desirable. There are some ERCP procedures that can be done on anticoagulation because they're considered low-risk, and those would include stent placement or removal, taking brushings, or just performing a diagnostic cholangiogram or pancreatogram. Those do not require discontinuation of anticoagulation or antiplatelet agents. Probably the most important thing to take away from this discussion is the importance of informed consent. As always, you want to review the procedure itself, and I typically ask my nurse practitioners, they actually will carry around a diagram with them of the liver and the bile duct and the duodenum because you can give, the picture tells a great story, and for especially patients who may not have a grasp of the anatomy of that area, which is kind of probably most people, a nice diagram really allows you to explain exactly what the patient should expect from the procedure. Obviously, you want to discuss the goals of the procedure, who is going to be performing the procedure, whether there are any alternatives, and then you want to take time and really review the potential for complications. Obviously, the most concerning complication is pancreatitis. Most studies quote a rate of around 5%, but in certain populations, it can be even higher than that. Patients need to understand that sometimes the pancreatitis is mild, but there have been reports of severe pancreatitis or even death following ERCP. Inflammation and bleeding are less common, but again, things to review, obviously cardiopulmonary complications, and then I think it's also important, especially if you anticipate that it might be a difficult procedure, just to let the patient know that we're not always successful. In good hands, ERCP is successful more than 90 and closer to 95% of the time, but there are times when for technical reasons or otherwise that the procedure just can't be completed. I think it's always a reasonable thing to review that with the patient and their family ahead of time. What to do after ERCP, post-procedure management, pretty standard. Most patients can start a clear liquid once they're awake from anesthesia, so I think a two-hour guideline is a pretty good one to follow. Obviously, if a patient has pain after the procedure and you're concerned about a complication like pancreatitis, then you want to withhold the liquids. Typically the next day, if the patient's doing well, you can advance diet, and then we're monitoring for clinical response to the procedure, and ERCP really is one of these procedures where there is a lot of times a very kind of quick response. Patients are jaundiced one day, and the next day they feel better, or they're itching because their bile duct was obstructed, and when you put a stent in, they feel well, but the itching is resolved within a day or two. I think it's nice to see that you have a good outcome after your procedure. And then very importantly, you want to make sure that you've got appropriate follow-up, so if somebody has had a common bile duct stone, make sure that they've got their surgical evaluation if they need a choicestectomy. And this is one of the most important things to remember here. If a patient has a stent that's placed, make sure you have a plan on what you're going to do with the stent. Obviously, that doesn't apply for permanent stents, but a lot of times we're placing temporary plastic stents, and if you don't have a good plan to have the patient come back to have that removed, there have been plenty of reports of people showing up years later with a stent that can no longer be easily removed. Okay, so enough on ERCP. Let's move on to endoscopic ultrasound. So endoscopic ultrasound is a very useful technique for a broad range of conditions. You can perform staging, diagnosis, and management of not just gastrointestinal diseases, but also non-gastrointestinal diseases. For example, in this case here, what you're looking at here is this is the echoendoscope here within the esophagus, and here's the aortic arch, and what you see on the other side is a mass, and this is actually a lung cancer. So EOS has the ability to diagnose and manage conditions that aren't even necessarily in the GI tract. Unlike ERCP, where the number of cases has decreased, the number of indications and procedures for EOS has steadily increased. And basically, it works by combining endoscopy with high-frequency ultrasonography. And so this illustrates the two type of EOS endoscopes that are used. On the left here, you can see a radial endoscope, and it's called radial because the ultrasound waves are sent out in kind of a radial pattern. And so you get this, the scope is always kind of in the middle of one of these screens with all the structures surrounding it. And so oftentimes, this is very useful for kind of getting a lay of the land. But if some type of intervention is needed, then typically, then we'll move to a linear endoscope. And you can see in this case, it's a different plane of imaging that the ultrasound waves are emitted. The advantage of the linear endoscope will be seen in one of the later slides. The first time you look at an endoscopic ultrasound, and even maybe after the first time, it often looks like a bit of a snowstorm. But if you look closely, you can often figure out what the different layers are that you're looking at. They correspond with the different layers of the intestinal wall. And so for example, there's oftentimes five layers that can be seen well. The top hyperechoic layer corresponds with the superficial mucosa. There's a second layer, which is hypoechoic, or it looks darker on ultrasound, which corresponds with the deep mucosa and lamina propria. Third layer, again, it's a bright layer, which is the submucosa. Fourth layer corresponds with the musculature propria. And if that particular part of the bowel has a cirrhosis, then you'll see a fifth layer. So I mentioned there are a number of indications for EUS, and this seems to grow all the time. But some of the most common things that you might refer a patient for an endoscopic ultrasound, pancreatic masses are one of the most common indications, and this includes both pancreatic cystic and solid lesions, subepithelial lesions throughout the GI tract, things like GI stromal tumors or leiomyomas that are visualized on a regular endoscopy. I showed you earlier how it can be used to evaluate a mediastinal mass. Also useful for liver masses, thickened gastric folds. If somebody has a dilated bile duct and there's no good explanation for it. And it actually is a very sensitive test for looking for common bile duct stones. It's incorporated into the staging of a number of different cancers, including esophagus, stomach, pancreas, lung, ampulla, and rectal cancer. And as I'm sure Dr. Call is going to review in his next discussion, there are a number of therapeutic options for EUS, including draining pseudocysts, doing pancreatic necrosectomies, draining the bile duct and gallbladder, performing celiac plexus block for patients with chronic abdominal pain. You can even embolize varices. And if ERCP is not successful, sometimes you can combine it with an EUS and then perform a successful ERCP. Here's an image of what a common bile duct stone would look under endoscopic ultrasound. You can see that this is the scope up here at the top. And then here's the common bile duct and the pancreatic duct. And right at the bottom here, you can see that there's this bright stone. And you can see there's a shadow behind it. So this would be kind of a classic example for somebody with a common bile duct stone. From there, you could proceed directly to an ERCP. Here's another image. This is using the other type of scope, the linear echo endoscope. This is the scope here. And then you see that there's a well kind of circumscribed mass right here. And then there's a needle coming out of the scope. Under direct ultrasound visualization, you can see it enter the tumor itself. And you can obviously get sampling, find needle aspiration with this procedure. The pre-procedural assessment, again, similar to ERCP, perform your usual risk assessment, make a decision on sedation. Many of these patients can actually be performed with MAC anesthesia. General anesthesia is not typically required. Manage anticoagulation appropriately. And then typically, antibiotics, again, are not necessary unless there's planned find needle aspiration of either a mediastinal cystic lesion or some types of therapeutic EUS are performed. Anticoagulation diagnostic EUS can be performed without stopping anticoagulation or antiplatelet agents. But if you anticipate doing some type of a therapeutic procedure like FNA, then hold anticoagulation as per other high-risk procedures. Informed consent. Again, review the procedures, the goals, who's going to be involved, what the alternatives are. Compared to ERCP, though, EUS is a much safer procedure. Pancreatitis is really very unusual. It would only be if you were taking like core biopsies of the pancreas. Perforation, bleeding, cardiopulmonary complications, and death, unsuccessful procedure. Fortunately, all these other things are fairly unusual. And as compared to ERCP, it is a much safer procedure. So I will finish with some practice pearls to summarize. ERCP and EUS are essential procedures for management of both GI and non-gastrointestinal diseases. Appropriate patient selection is extremely important, especially as regards ERCP because of the risk of complications. Less invasive and risky tests really should be chosen whenever possible. Good management of the anticoagulation and their operative risk is important. And early recognition and management of complications is essential. And that concludes my discussion. I would like to just go through a couple of quick polling questions. Eden, thank you. So which of the following test is most appropriate for evaluation of a patient with a low suspicion of choledocal lithiasis or a common bile duct stone? ERCP, ultrasound, MRCP, or abdominal CT? Okay. So MRCP is probably the most appropriate. I can see why ultrasound would be a reasonable thing to look as well. The problem with ultrasound is that the sensitivity for identifying common bile duct stones is only about 30%. So even if you get a negative ultrasound, it really doesn't, in my mind, eliminate the possibility that the patient has a common bile duct stone. So if you really are trying to determine a yes or no on a common duct stone, MRCP is the way to go. Okay. Next question. Which of the following are complications of ERCP, pancreatitis, bleeding, perforation, hypoxia, all of the above? All right. Very good. So that kind of speaks for itself. And let's go on to the last question. EUS is indicated for which of the following, diagnosis and staging of pancreatic cancer, endoscopic pancreatic pseudocyst drainage, FNA of mediastinal lymphadenopathy, or evaluation of unexplained common bile duct dilation, or all of the above? Great. And with that, I will hand the microphone back to Vivek.

ERCP

EUS

pancreatic diseases

biliary diseases

patient selection

complications