I will be going over what we use to guide our standard practice in terms of ERCP, pancreatic obiliary work. And so the objective is really to go over not only ASGE guidelines, but what other guidelines do we have out there that's evidence-based and helps us take care of our patients safely. Now just to point out, mainly I'll be referencing ASGE guidelines as well as ESGE guidelines. That's the European Society of Gastrointestinal Endoscopy. And then the third one that tends to have some endoscopy-related guidelines is going to be the ACG, so American College of Gastroenterology. The way these guidelines are all organized, and it's something that it's going to be like a 30-page guideline that most of us don't read sentence by sentence. But the way you really look at it is that they have these recommendations, so your bold statement recommendations that they have based on a clinical question that I have. Lots of things that we talked about today, what stent is better than that stent? They review the literature, the studies that have looked at these, and then they make a recommendation based on it. Based on that recommendation, you should also look at the quality of evidence that supports it. In pancreatic obiliary work, you'll see that there are actually very few super strong, strongly evidenced recommendations, because most of the stuff that we are working on, a lot of it's based on retrospective studies, or we only have a few randomized control studies so then that's something that you'll also encounter a lot when you're working with anybody in advanced endoscopy, is that there's a lot of different ways to do something. So I always tell everybody that I meet or train, I say, look and try to keep your mind open to every single way that people do things, but always ask why, because if the why makes sense to them, it should make sense to you too. And so there's different ways to do stuff. So going through these slides is just really not to go through granular detail as to what the guidelines are, but really to touch based on what types of guidelines we have out there. So then you have maybe a quick reference to go to if you have a question about something, especially after going through and meeting with your physicians. So looking at the basic procedural aspects, we have our first one, both ACG and ASGE have quality indicators guidelines. I won't go into detail with that one, because we did have our first lecture by Dr. Shahal talking about the different quality indicators, pre-procedure, you know, with consent, making sure the indication is correct, looking at what medications they're on, et cetera. So you can go into that for a full length description as to the quality indicators, the evidence behind it as well. Next I want to point out, ESGE is the only body that talks about biliary cannulation and sphincterotomy in terms of guidelines and how they recommend, they define what a difficult cannulation is. So how many times we touch the papilla, if we access the pancreatic duct. So it goes into granular detail about what a difficult cannulation is. If we fail cannulation, they talk about the evidence behind the different techniques for that. We've mentioned pre-cut sphincterotomy, fistulotomy, over the pancreatic duct stent or not over the pancreatic duct stent. So there's a lot of words that I'm not sure if you guys all know what they are, but we mentioned before pre-cut is a cut using a needle knife without any access to the duct. Repetition is key. So hopefully if you hear it like 10 different ways, it'll stick. And then fistulotomy is when you do a cut, you're going above the ampula. So the biliary and the pancreatic orifice, you're going actually above in the intraduodenal segment. So kind of like that hump that you see, you're cutting above that. And we saw some nice videos earlier of that as well. And then you can do it with or without a pancreatic duct stent that's in there, and that depends on whether or not you had access to it. So they talk about the different techniques if you are not able to traditionally cannulate with a sphincterotome. And then also the biggest thing that they talk about is reducing the risk of pancreatitis. We went through a lot of that earlier because that is the dreaded adverse event in patients, especially if they go towards the severe necrotizing pancreatitis. More on adverse events, we have a lot of data out there, a lot of guidelines I should say. ASGE has one on adverse events associated with ERCP. So does ESGE. And then specifically because we talk about the post-pancreatitis, or excuse me, post-ERCP pancreatitis, ASGE has specific recommendations on how to reduce the risk of post-ERCP pancreatitis as well. So as you know, the biggest thing we talk about is the pancreatitis. We've reviewed bleeding. There's also infection, perforations. And then cardiopulmonary events related to both anesthesia and prolonged sedation. So these, again, guidelines go through. The evidence we have out there gives us the ways to reduce these risks, but also how to recognize and how to treat afterwards. Choledocholithiasis. So choledocholithiasis is your bile duct stones. Everything's going to be rooted in your Latin. So chole is your bile, doco is going to be your duct part, and lithiasis is your stones. You're going to hear this, choledocholithiasis is all of your bile duct stones. ASGE has a guideline for that, and then ESGE as well. A big part of it is helping us guide how do we determine whether or not there is a true stone in there. Because we said, you know, these procedures are not low risk, and so we definitely want to go in there only if we have good evidence that there is a stone. It's based on our labs. Usually bilirubin is elevated. Our duct size. Any imaging support that can tell us if there's a filling defect. Usually we talked about earlier, anyone who walks through an emergency department will get a CAT scan these days, but an ultrasound and MRI can help us find smaller stones that may not be caught. And next would be determining the timing of ERCP, whether depending on how sick they are, when would be the best time to intervene on someone. And then also recommendations on timing of cholecystectomy. So when someone still has their gallbladder in there, and they present with stones in their bile duct, the next step would be after we remove the stones in the bile duct is to get rid of the gallbladder if the patient is a good surgical candidate. And the reason for that is that it can happen again, potentially. And so, again, guidelines on how to treat stones as well in here as well. So we talked earlier about limited sphincterotomy, balloon dilation, and then the techniques to remove stones. It's all in these guidelines as well. And so, again, these, you're going to read them, and they're going to, a lot of it's going to say conditional recommendations, because you're going to see that each physician is going to do it a little differently. Can I take a question right there? Representing St. Louis, we have Tess. You mentioned, like, duct sizes. How do you guys determine? I feel like I've heard a lot of, you know, everyone saying, like, yeah, when we, you know, know the sizing and everything, like, what do you guys use, or what imaging do you recommend for you to actually have all that information before you even go in? Yeah. So, actually, CAT scans, we usually have a CAT scan on a patient, you know, when they are presenting with something, especially with a stone. A CAT scan's usually the first thing a lot of our adult patients get. Pregnant children, they usually get an ultrasound. They can actually measure the duct size. And so a lot of the times, you'll measure either the common bile duct or the intrahepatic bile ducts. They'll give us an idea. I always, if they're, if they just say dilated or, you know, minimally dilated, I get on the phone with my radiologist and ask them for the size. Now, there's the other question of, like, when you're in the ER, or I get this a lot from my fellows, too, when you're in ERCP or doing the ERCP, how do you estimate the duct size? Because it's not like you have a picture on your computer where you can drag a ruler. My rule of thumb is that the scope is around 11 millimeters, so then if I can kind of put my finger there and against the bile duct, it gives you, like, a rough estimate. The other thing is that you have your balloon, your stone extraction balloons that are a standard size that you're using as well. So if you inflate that, and you can see how much it's, like, either pressing against the duct or maybe not even filling the entire duct, you can use that to estimate the size of the duct as well. Cholangitis. So that is infection of the bile duct. ASGE. And actually, the Tokyo guidelines coming out of Japan, they're really kind of the forefront in bile duct and gallbladder infections. And so, again, this goes down to what the clinical diagnosis of cholangitis is. And so that is something very specific that we always use. Diagnosing cholangitis is clinical, meaning that you have some objective data, but then you have to put it all together in how the patient is presenting as well. So these guidelines go through the specific diagnosis of a patient with cholangitis. It compares ERCP to IR, interventional radiology, with their percutaneous drainage. So they compare studies, or they review studies that compare the two types of drainage. And then also timing of ERCP. The ASGE guidelines kind of take in a lot of studies that say, can you wait 12 hours, 24 hours, 48 hours? Tokyo guidelines similarly. And so it basically tells us if someone is hemodynamically unstable, meaning that they are on medications that are having to keep up their blood pressure, usually 12 hours or less is the general consensus. And then usually if they're not, 48 hours is the next. And one of my mentors said it's because no one wants to come in on the weekends. So if they're stable, you can do it on Monday. But usually my GI lab is open pretty easily, so we usually can just bring them in on the weekends. We talked a lot about biliary strictures. There are a lot of guidelines on biliary strictures. This is first the approach. My next slide will go into the guidelines for malignant biliary strictures. So the first one is always talking about approach to biliary strictures. It depends on is it extrahepatic, meaning that is it below the liver, so usually the common bile duct, or is it intrahepatic, the ducts that go branch into the liver? Because if it's usually extrahepatic, the biggest way we want to start approaching it is using endoscopic ultrasound first and taking a look and seeing where that mass is, seeing if there's lymph nodes around there for us to biopsy. It just better characterizes the stricture as well. Is there even a mass? And that will help us. Next is going to be determining malignant versus benign strictures because how we approach these strictures as we've gone through is very different. A lot of the times that last one, ASGE, indeterminate biliary stricture slash possible malignancy, I have patients that have strictures and I just don't know what's causing it. We typically treat it like it's malignant until proven otherwise because the last thing we want is to miss a cholangiocarcinoma, which is a cancer of the bile duct. These can be very difficult to diagnose too because you've heard before, brushings. Brushings are going to give you at most a 50% sensitivity of being able to catch cancer. And that's with like that 30 brush. I was the first one to ask one of my techs to do 30 brushes. And she just looked at me like, are you kidding me? Because those things can break. It's really hard to do sometimes. So anyways, these stricture guidelines kind of tell you how to approach it. A lot of the overall theme is it's malignancy until proven otherwise, unless you have a strong clinical evidence that it's not malignancy. I don't want to derail you, but this has been mentioned several times today. Ish as it relates to brushing. Can you just explain a little bit more? So brushing itself is the technique. So you hear the cytology brush. It's basically a long plastic catheter with a little fuzzy brush tip. And so that itself, we call it the cytology brush. We put it across the stricture, and we brush it. Classically, we send that to cytologists so that's the pathologists who look at the specific cells on a slide. FISH, F-I-S-H, all in caps, is a fluorescent immunohybridization, in situ hybridization. So it is a type of test where then they look at the genetic makeup of the actual cells itself to see what looks potentially cancerous. And we send ours up to Mayo as well. There's some good studies out there that show that even though on the slides, the cytology cells say, hey, it looks weird, atypical, but it's not truly. They can't say it's cancer. Sometimes FISH can be a good complement because they say, hey, the way these cells look or the way they light up, essentially, that makes it more likely that it is cancer. Is that a common thing? They're looking at the chromosomes. And normally, you should have 23 pairs, right? So what they look for is the change in the number. So in cancers, you have abnormalities in the number of chromosomes. So if you have more chromosomes and the type changes, then that is being used as a surrogate for cancer. So they're looking at that chromosomal level based on diet. Correct? Correct me if I'm wrong. So they're looking at what we call aneuploidy, which means odd number of chromosomes. And so not only the odd number, but they also look at changes in or mutation in certain chromosomes. For example, 7P chromosome. So there are certain changes which they have identified are significant of underlying cancer and certain changes which denote that this could be just inflammatory. So it's like a chromosome analysis. Aside from access, when you're talking about the sensitivity of the brushing being, it sounds quite low. And then in combination, we're still at a coin flip scenario, which I would assume is not difficult to direct with a coin flip. Outside of access, why would you not perform biopsy, for instance? It may prevent their ability to get a transplant. So when you do an endoscopic ultrasound and place your needle through and collect the tumor cells, you can get seeding of the tumor cells. So you typically don't want to pass the needle. So that's E, U, S, F, and B, where you're asking biopsy through a clean needle? Fluoroscopy, you could do that. Oh, yes, yes, yes. So that's what we, I actually don't, I do brushings for the sake of brushings. But I actually just throw a pediatric forceps up there. And I take biopsies. Of course, that's really great for distal, meaning closer to the papilla, because you're not just under fluoroscopy, like guiding a stiff device going up there. But I've gone up to the hilum. I won't let my fellow go up to the hilum. I'll go up to the hilum and take little bites up there, too. And that's where cholangioscopy comes in, too. My algorithm is usually, I usually do brush and pediatric forceps first. If I don't get an answer, I might bring them back for cholangioscopy. But the only reason for that is more logistics. My institution does my patients, we do under MAC. So we don't do general anesthesia. So if we have to switch over to cholangioscopy, we then have to intubate the patient, which extends the procedure time. So that's just more logistics. But a lot of places would just go over to cholangioscopy and just get direct vision biopsy. Thank you. And since we're on the topic, and it's a recurring theme, there is a concept of increasing yields. So cytology, when it's positive, is great. Negative is useless. If you get it with the cytology, you're good. It's just that the chance of you getting it is low. It's like winning the lottery. So with histology, when you take biopsies, the yield is good. But oftentimes, you may not get the right tissue, especially in the fluoroscopic. I have exactly the same thing. But that's where people say, OK, why don't you just do cholangioscopy up front? There, one of the risks is that you have an obstructed system. So now you're pushing water into an obstructed system. So it's not unreasonable to stage it. You'd wait for these two and then come back for cholangioscopy as needed. And aside from fish, the other thing that Dr. Chahal mentioned is billy sequence. So now the next level of molecular testing is actually looking for genetic mutations, like at the level of specific genes. And they can run these assays where they look for genes. So you could theoretically do brushing for cytology and molecular testing and biopsies, send that off. And if any of those come back positive, you're good. If they're negative, then you go back to cholangioscopy. Thank you. All right, so approach to biliary strictures more specifically for malignancy. So ASGE both have guidelines on biliary neoplasia and specifically malignant hyalurobstruction. So you have, in terms of just overall biliary neoplasia, we are including ampullary adenocarcinoma too, so just cancer right at the ampullary orifice. And Dr. Lee had mentioned earlier, a lot of these we remove endoscopically now, as long as it's not extending too much into the bile duct. One centimeter is usually our cutoff. If it extends more into it, the likelihood of us getting everything or removing everything is lower. But the goal is to do things endoscopically now. And then, of course, with malignant hyalurobstruction, the reason for such a huge guideline for that is the reason why we just had a huge lecture on that is just there's a lot of nuances with it with regards to each endoscopist's approach to how much of the liver to drain, as you heard newer evidence coming out that we may need to drain more than what we thought previously we needed to, and then all the different stents. Benign biliary diseases, so we talk a lot about cancers and strictures, but there are a lot of benign reasons why we get stricturing as well. And ASGE and ESGE both have different guidelines on that. So types of benign biliary strictures we talk about. We heard primary sclerosine cholangitis. That is a type of disease where it causes stricturing throughout the entire bile duct tree. So it could be in the branches, could be in the main one. This increases your risk of developing bile duct cancer, so cholangiocarcinoma. And so you hear that word earlier, dominant stricture. That dominant stricture tells us, and its definition is it is 50% smaller than your normal, the rest of the ducts. And the length of it is, gosh, I'm like 1.5 centimeters. I was going to say 2, 1.5 centimeters in length. But that's usually determined by an MRCP beforehand. We mentioned before, we don't want to manipulate or instrument these patients unless we have to. And a dominant stricture is a big indication. Bile leaks, we talked about earlier, too. Post-liver transplant stricture, we talked about earlier, where they reconnect the donor duct and the recipient duct. Or if they do a transplant where they connect the duct to part of the small intestine, strictures can happen there. And then IgG4 autoimmune cholangiopathy is just an autoimmune disease that can cause scarring of different parts of the bile duct. I think in one of the AI videos earlier, they had mentioned that. Now, these are different guidelines to how approach these diseases and, again, the evidence behind. ESGE has a great guideline on biliary stenting. So we talked a lot about stents today, different types of plastic stents, and why you would choose one stent over another. And again, a lot of it is head-to-head trials. Some of it is just expert recommendations based on review of the stents out there and how we use it and its results out there or the outcomes of using each stent. So this is also a really good review paper of the different types of stents as well. We talked earlier about the main groups of go through plastic, so plastic biliary, plastic pancreatic. But in this case, they review the biliary stents. And then you have your uncovered metal stents and your covered metal stents. I think before, someone mentioned partially covered stents, but I don't think we have that really in use a lot here. So you're going to see those primarily. And so it's a good review to go through that one. And again, you're going to talk to your physician, and they're going to say why they use certain stents. It's always nice to hear why they use certain stents. Sometimes it's just because they don't carry it at that facility. I trained at a state facility. We didn't carry straight biliary stents. We only had double pigtails, just because someone who had been working there for a really long time only used double pigtails. And it works, but there are specific, for me, personal reasons why I use a double pigtail versus a straight stent. Sometimes it depends on the shape of the duct, how tight the stricture I'm trying to get through, things like that. Last but not least, chronic pancreatitis is the, we went through a lot of biliary stuff. This is going to go into reasons why we would do ERCP or ERP. And ASGE and ESGE goes through when we would use endoscopic treatments for chronic pancreatitis. Usually with the scarring of the pancreas, you can get scarring then of the duct, where some areas get scarred down more than others, and it causes a stricture. And so you get pancreatic duct, or PD, strictures. Stones can form. We saw that earlier. So very calcified, hard stones can occur, too. We talked already about earlier ways to treat these stones, either through extracorporeal shockwave lithotripsy. You'll hear the word SWAL, E-S-W-L, so S-WAL. That's usually through urology can do it. Our institution's really lucky. We actually have a portable SWAL machine that comes and gets set up across the hall from us, which is really easy. It's nice, because then afterwards, we take them straight for ERCP to clear the stones. And then pancreatoscopy, we saw that really cool video earlier with the laser. But you can use EHL probes as well for that. And then, of course, biliary strictures that can happen in chronic pancreatitis. Dr. Lee, I think, was talking about that earlier as well. The bile duct goes through the head of the pancreas, just that distal end. So when that scarring or that rubbery pancreas happens, it just presses down on that bile duct. Other resources, the ERCP book is on its fourth edition. And that kind of goes through, actually, the first few chapters are all about the devices, the scope, the devices. Other things that I found really helpful, actually, when I was a fellow was the ASGE master class. They have a basic ERCP one that may have sunset already. But the advanced techniques in ERCP comes every few years. And that's really useful, because they kind of go through the basics of ERCP and then all the different devices or different methods incorporated in ERCP. Of course, colleagues, this is our kind of overall resources. Phone a friend. I'm always on the phone with someone else if there are complicated things going on. Intra-procedurally, I use FaceTime. And someone will help me through. That's about it.

ERCP

ASGE guidelines

biliary cannulation

chronic pancreatitis

diagnostic techniques

patient care