So, diagnostic colonoscopy. Nothing to disclose. Objectives, as expected, we'll talk about indications, contraindications, your technique, which I know all of you have perfect technique already, and then troubleshooting. Now indications for colonoscopy, the main reason we do colonoscopy is one of the largest indications is screening, all right? And that's been one of the benefits for gastroenterology because we get to perform these procedures in many, many patients, most of whom are healthy. And then you can divide them into average risk or high risk. And as you expect, higher risk are patients who have perhaps a family history of colon cancer or perhaps a hereditary syndrome. And average risk are your routine patients who are older than age 45 to 50 with perhaps no family history. Surveillance colonoscopy is technically defined as the colonoscopy where there's a history of pathology. So there's a history of an adenomatous polyp, something else that you've taken out in the past. So that would be a surveillance colonoscopy. And then they are on a different sort of schedule depending on the prior pathology. Recent guidelines suggested that depending on the size or pathology that was found before, you can bring them back in three, five, seven, 10 years. Indications for colonoscopy, diagnostics. So this is a third other major reason for doing colonoscopies. And what you'll primarily see in your first year while you're inpatient, right? Someone comes in bleeding, hematochezia. We've got a real lot of colon cancer. Or they have melanoma, and we took out a polyp from the cecum. It could be a post-polypectomy bleed. Iron deficiency anemia, a common consultation while you're a first year fellow. Inflammatory bowel disease that's suspected or known. Or abnormal imaging of the colon. We see colitis. We've seen it a few times. We think it could be Crohn's. Unexplained GI symptoms and signs. So that's the most common thing you will probably come across as first year fellows. Contraindications. So this is very important. As a proceduralist, you have to know when to do something and also when not to do something, all right? Now, very exciting when you get a lot of consults, say, sure, yes, definitely. But what are the contraindications? Some of these are sort of relative. And in fact, most of them end up being relative, especially when you speak to surgeons. But there's some hard and fast contraindications. Perforated intestine. It's obvious, obviously, that if someone has a hole in the colon, it's probably not a good idea to go in and put some more air or carbon dioxide. Sometimes there are some exceptions when surgery is asking to help with closure, for instance. But in general, perforated intestine, no, right? Acute diverticulitis, deep ulcerations, severe ischemic necrosis, fulminant colitis. What do those all have in common? Perforation risk, right? You can think about it. You can imagine that the lining of the intestine, the colon intestine, even though it's thin, it's pretty resilient. It's got multiple walls. It's got two muscular layers. But if you start to erode into it with an ulceration, you start to inflame it with some diverticulitis, you start to eat at it with some necrosis, there's a much higher risk of perforation, especially if you're pushing into it with a scope, making a turn, or if you are inflating it with a lot of air and it's getting thinner. So that is a relative, or that is a contraindication for colonoscopy as well. This is one that is important, but we tend to overlook it from time to time as first year fellows. And what I'm saying is cardiopulmonary decompensation. Patients are getting sedation, they're getting anesthesia for quite some time, 30 minutes, 40 minutes, 45 minutes, an hour, depending on the indication. And if they are already at poor reserve because they have some issues with their lungs, some issues with their heart, you can imagine there could be a complication. And so it's very important to get that past medical history. You don't want someone rolling in and you're telling, you're attending, the EF is less than 5% and they just got shocked a few days ago, but they look great. Primary team tells me they look great. So you really want to make sure that you have an understanding for the reserve of that patient. Cardiopulmonary complications are common, unfortunately. And you really have to, in your HPI, focus on your underlying cardiac and your underlying pulmonary history. Also don't trust the primary team. So basically all of our attending is essentially internal medicine, but things change rapidly when you're in the hospital. You have to see them the day of the procedure just to make sure that now they're not volume overloaded or now they're on four liters when previously they were actually not on oxygen. Things do change quickly when they're in the hospital. We all know that. Inability to tolerate bowel prep. So that's self-explanatory. So colonoscopy technique, we're starting with a careful perianal exam. And so you're looking for things on the outside. So if someone has Crohn's and so on, you're looking for fistulas. These are three of the examples they placed here. Sort of here, they're looking at some prolapsed internal hemorrhoids or in this patient, maybe some rectal varices. Here this was not such a good example, but some thrombosed external hemorrhoids. And here you can kind of take a look at it, even though I know you haven't seen as many yet. But this just doesn't look right. It probably is a condyloma or some kind of neoplasm on the outside of the anus. So a digital rectal exam is a full sweep of the anal canal. In general, the rectal exam is also to facilitate and lubricate. So facilitate the scope entering the intestine, entering the rectum. But it's important to do a proper digital rectal exam. Full sweep of the anal canal, prostate examination in males. Technically, a normal exam means that you haven't felt any prostatic nodules. But you want to do a proper exam. If there is a lesion in the rectum, you want to have felt it so you can take a good look at it. You really want to do a full sweep of the anal canal. And you want to talk to the patient, say, OK, sir, you're going to feel, or OK, ma'am, you're going to feel my finger, and talk them through it. So when you're entering, it can be uncomfortable. Because the sedation, yes, is there. But it hasn't quite kicked in yet. All right, anal intubation. What is wrong with this picture? Can anyone tell me? They're not wearing any gloves, all right? Don't do this, all right? So 2021, please glove or double glove before doing this. So you want to take, use your scope, take a good look at the anus. We just saw those pictures earlier. Sometimes you have to open the anal cheeks to take a look at the anus. And then what you want to do is lubricate. And then you kind of guide the scope in. So by putting your finger in, you have an idea of where the scope will go. And you follow that same path with the colonoscope. The position of the scope, there are a couple of ways you can do it. Flat on the bed or hanging over the side of the bed. And you'll see different attendings do this, or they favor one way over the other. Or they'll use both during the same procedure. Now if it's flat on the bed, it's easy to rest the scope on the bed. You can see that it's probably easier to advance in and out. Hanging over the side of the bed, what you can sometimes do because it's hanging over the side of the bed, and Dr. Sheth I know likes to do this as well, you can pin it with your hips or with your thighs. And that allows you some more stability. So take a look at how your attendings are positioning the colonoscope. Because that does help you to stabilize the scope. That does help you to navigate turns. Basic rules of colonoscopy, all very self-explanatory. Do not advance the colonoscope without a clear view of the lumen. So if you can't see where you're going, just like you're driving a car, you stop. The classic thing you'll also hear is white out. So when you're pushing against the wall of the intestine and it's getting white, that's when you're really stretching it, okay? And that's when it's a no-no. Really you have to pull back. You're worried sometimes if you pull back, you know, I've really got around that turn, I've gotten far, you may fall back. And you may. But the main thing is do not advance without a clear view of the lumen. When in doubt, pull back. That's a golden rule that we all follow. Do not advance the colonoscope if there is resistance. So what is meant by resistance? And this is something that's a feel that you will get over time. Obviously there's some, you can obviously know when it's a fixed resistance, when it's a very stiff and it's very hard to advance it. But there are other times when it's, you're forming a loop and there's milder resistance or more moderate resistance and you can push through the loop and this will come with time and this will come with direct supervision from your attending. Use as little air as possible. So before the advent of carbon dioxide, and I know one of the other speakers suggested pretty much everywhere is using carbon dioxide now, which I think is true. Patients would wake up and they could be in a lot of pain. And it was not uncommon to have rectal tubes in the recovery room, really advising them to get up and walk around with carbon dioxide. A lot of that has been eliminated. So now we can let fellows hold a scope for a lot longer without worrying about air retention, which is good for you, good for us. But carbon dioxide is sort of, to some extent, the game changer, but still, you want to use as little air as possible. I tend to have my finger on the carbon dioxide when I first start off, open up the rectum, open up the sigmoid a little bit, put in a little bit of water, get around, and then typically I'm by the cecum in a few minutes. And that's typically where most of us are. But you'll find that especially when it's a twistier colon, some people will use a lot more water to weigh down and straighten out the sigmoid. You'll also find that when you're first starting out, you may also use a little bit more water to kind of open things up without being ... It allows you to lubricate the scope and move around things a little bit easier. But water and carbon dioxide are both useful. Try not to use too much CO2. Keep colonoscope lubricated. I just spoke about that with water. And pay attention to the patient's level of discomfort. So sometimes you've given them a lot of sedation, you're there, and the patient's waking up and they're in pain. You're like, the cecum is right there, sir, hold on, I'm almost there, please just let me get there. So you've got to pay attention to the level of discomfort. Just hold on, just stop. You will get to that cecum, all right? Trust me. We have three years of fellowship. But really, pay attention. Okay, let's see what's next. Anatomic landmarks. Okay, so it's all relatively straightforward. Rectal area usually within the first 10, 12 centimeters. Sigmoid to descending colon ... It's a little bit harder for me to use the pointer, but sigmoid to descending colon. Hepatic flexure, right on the upper right. And you can see it has a bluish hue because the spleen is right next to it. Transverse colon along the top. Hepatic flexure where it turns again on the left-hand side. The liver is there, so it also has a little bit of a bluish hue. Then ascending colon as you come down towards the cecum and the terminal ilium. Now the rectum ... I think this is a video, and let's see if it'll play here. Maybe not. All right, so let's see if I can go back. So the rectum here has these deep folds, and this is the one thing, one little pearl is that as you're withdrawing and as you're looking at the rectum, it can be easy to miss lesions behind these deep folds, these deep rectal folds. Really use tip control and make sure you pay attention to the folds, to the mucosa behind the folds. The transverse colon is really easy to identify. It's a more triangular, transverse, triangular shape, and this is after you've gotten beyond the splenic flexure. The cecum and ileocecal valve you can see on the left corner of your screen, that little opening to get into the terminal ilium, that's the ileocecal valve, and the appendiceal orifice is ... can't see it as well here, but a little circular kind of opening that's within the cecum as well. So terminal ilium intubation. So this will come probably a little bit later. The first thing is to get to the cecum, but the idea is oftentimes you'll want to try to get into the TI. Can you think of some reasons we may want to get into the terminal ilium? Crohn's is one of the big things, right? So terminal iliitis or Crohn's disease, so you want to get in, take some biopsies, see what there is. Other reasons, sometimes there may be some AVMs that you want to look for. And so it's nice to typically practice getting into the TI, but it's not necessarily needed for all colonoscopies. Oh, it looks like this video is playing, which is great. And what it shows here is that one of the tips for getting into the terminal ilium is to deflate the colon, deflate the cecum, and allow the IC valve, allow the mucosa to have better contact with the colonoscope. So you can see here, they're deflating and then they're pulling back, and the opening is becoming more apparent and they're pushing into the terminal ilium. So deflate, pull back until they found the IC valve, very gentle pullback, and it opened up and it pushed into the terminal ilium. I know easier said than done, but in general, if you have good technique, it's not that hard to get into terminal ilium. Now landmarks for the lumen. Now one of the big things is diverticulitis. Once you're above age 50, about half the population probably have diverticulitis, probably more. And this can be the scourge of fellows, because you see this hole, and you're like, okay, that's it. I'm going. But that could be a diverticulum, and you don't want to go into that, because then you could perforate. And that has happened, unfortunately. And the other thing is that when you have diverticular disease, sometimes the colon becomes more narrow. The colon becomes twistier. It's harder to get around. It's easier to fall into a diverticulum. You have very large-mouthed diverticula, as you guys have seen from doing colonoscopies already. And so you have to navigate sigmoid, you have to navigate diverticula with care. Some of the tricks is that the diverticula will line up. It's almost like, you know, to connect the dots things we used to do when we were little. You can connect the dots of the diverticula, and that will point, that will be aligned or point the way in the direction of the lumen. So just go very slowly, go very carefully, listen to your attendings, and think about connecting the dots of the diverticula. That points you in the direction of the lumen. Loop formation. So you can see here that as you're pushing the colonoscope in, you can not necessarily advance the tip, but you're just forming a loop, right, at the top. And so this video is showing you the different areas within the colon where you may form the loop. And you can think about these are the parts of the colon that are not fixed down. These are the parts of the colon that are sort of more within the peritoneum. So what they're speaking about here is this sort of paradoxical motion, which I know all of you have had already, because we all had them during colonoscopies. When you're pushing, but it isn't moving, right? Or when you're pushing, and actually it's coming back, perhaps. And that's because the vector or the force is going into the loop. It's not going into the tip. It's not propelling you forward, right? And that's what makes colonoscopy hard, these things, or else sort of anyone can do it. That's why we need several years of fellowship to really master colonoscopy. So predictable areas of loop formation. Your techs know this very well, because they're very, very helpful for us to get to the CECM and for applying abdominal pressure. So the fixed areas that are more retroperitoneal, you tend not to loop as much, so they're sending a descending colon. But a sigmoid colon and transverse colon, which are more flexible, floppy, are the areas where you can imagine that the scope will just bow into or loop into. So how do you reduce the loop, all right? So you can see here, they've talked about two ways, pull back or torque, okay? Let's see if that plays. And we can show it in this video here. So one-to-one transmission, and you can see here, definitely wearing very good gloves for this procedure. So inserting the scope one-to-one, and that's when you know there's no loop. As you advance, it's going forward. As you pull back, it's coming back. So the most important technique for colonoscopy is pull back to straighten. So in those last few slides in the video, the idea is that as you advance forward, you're going to have a loop. Sometimes you push through it. But in general, as you go around turns, that's where you tend to begin to introduce loops. And as you go around a turn, you know you've kind of put a little loop in, so pull back a little bit before you go forward. As you're pushing in a loop, you pull back. That's the first step to taking it out. Torquing usually clockwise or rotating to the right will also sometimes help you to pull that loop out. It'll take time as you do more and more colonoscopies, but in general, that's what most of us do. As we go around turns, we'll pull back a little bit. As we go forward and we're introducing a loop, we'll pull back a little bit. After having pushed through and introduced a loop to get somewhere, but knowing we have to take it out, we'll pull back quite a bit, usually by torquing right as well, and that helps us to remove a large loop. Now getting around, you've taken the loop out, but every time you go, you put it back in. What are you going to do? So you try to avoid putting the loop in, and this, you can imagine, will probably be best by actually putting some pressure on the abdominal wall to prevent the loop from forming in the first place. So this is where your techs are very, very helpful. And usually, they all have some little tricks in terms of how to get you around, but the idea is that they know there are certain areas, such as over the transverse colon or over the sigmoid colon, where you tend to form loops, and they'll apply a lot of abdominal pressure to that. So the patient is on the left lateral, they're applying pressure to those sites, or you'll turn the patient supine, so it's easier for them to give abdominal pressure to prevent you from forming a loop. So they'll actually feel your scope, and sometimes you should also do this as well, especially if you're assisting. You can feel the scope, and you're basically pushing on it to avoid the loop formation, to allow you to propel forward, and finally into the sigmoid, all right? So non-specific abdominal pressure, so sometimes, and I've seen some techs do it, you have no idea what's happening, so you kind of put abdominal pressure over the entire intestine. But in general, you tend to be a little bit more focused. So hepatic, if you're kind of looping maybe an hepatic flexure, you perhaps want to put abdominal pressure on the splenic flexure area. When you're about 20 to 25 centimeters, maybe it's more lower, suprapubic, 25 to 36 centimeters, left lower quadrant, 35 to 50 centimeters, left mid-abdomen. This is sort of rough estimates. You'll pick this up with time, with doing more and more colonoscopies. Abdominal pressure, suprapubic, this assistant is also not wearing gloves, but you pull back to reduce the loop, then you apply suprapubic pressure as you advance to prevent that loop from forming. All right, this is also self-explanatory. Pull back to reduce the loop, then use the pressure to advance to prevent the loop from forming. Now, at this one, at 35 to 50 centimeters, they anticipate that a scope tip, and as you can see here in the images, is in a transverse colon. So they're applying left mid-abdominal pressure now to help prevent the bowing of the endoscope, because you can see that they expect it's bowing up near the splenic flexure. So it's relatively straightforward. Essentially, you're applying pressure where you think the scope would loop or would bow. This is a nice tip here for getting beyond the hepatic flexure. Two leading experts and ASG members, and currently our current president, Doug Rex and Michael Bork, both realized that there is a nice technique for allowing you to advance further into the right colon by rotating the patient first halfway back to supine, so moving only the shoulders. The concept that I want to get across to you, I know you're all reading this, is that subtle movements can be very helpful. So it's not just applying abdominal pressure, it's also rotating the patient. You'll see at times, getting into the right colon detects or attending, so rotate the patient a little bit more supine. And just that motion of rotating a little bit will help you propel you a little bit further. Or sometimes they'll rotate them supine, but they won't throw them all the way, they'll rotate a little bit. And again, just that motion will allow you. Now what do you do, though, if you have somebody you can't apply abdominal pressure to, such as a very large, obese abdomen, which unfortunately is not uncommon? You pray? All right. So all those are great. The idea is that you're seeing this more and more, these larger abdomens, obese, it's harder to apply pressure. Some attendings will start off with them prone, as I know one of the audience members suggested, the patient themselves applying pressure will allow you to get around without looping. You try your best. And in most cases, with abdominal pressure, you are able to get around. Endoscope withdrawal. So we're shifting gears in the last eight minutes. What do you want to do is make sure you clean, clean the colon. You flush it, and you suction the fluid out. Always remember the suction is at about 6 o'clock, so you want to be above the water, so you can make sure you aspirate all that fluid into your scope. Really important to check behind foals. Remember what we said earlier, those deep foals behind the rectum, make sure you don't miss that. There are also deep foals that tend to be in the right colon, and you really want to make sure you use tip control to look carefully behind the foals. Look to the top, look down, look to the left, look to the right. Really check behind the foals. Retroflexion. Cecal retroflexion is something that's been reported on that may increase your adenoma detection rate, especially in the right side. And the idea is that you push the scope in. While turning the little wheel to the right, for instance, and torquing as well, and that allows you to see behind you. And so you see the foals from a different direction. Be meticulous. It's very important. There was a nice study that showed that there were more than one person, when a fellow was involved in a colonoscopy, the adenoma detection rate went up. Because more than one person is looking at the screen, you're not fixed, you're able to really keep an eye and make sure you're not missing those small polyps. Retroflexion. So this is retroflexion here in the rectum, which is the most common place. You want to visualize the anus and the dentate line before starting the maneuver. And then what you're doing is gently advancing the scope in to about the first fold, while big wheel is coming all the way towards you. You can see that here. And then pushing in gently while rotating the little wheel either to the left or to the right. In this case, rotating to the left. And then here, rotating the scope or turning it around so you can have a good view of the dentate line of the hemorrhoids, internal or external. So again, what do you want to do? Take a good look, advance slowly, big wheel towards you while advancing slowly, and then little wheel to the left or to the right, and torquing to bring the dentate line and your anus into view. So in summary, in the last few minutes, you want to really review the procedural indications. Why are we doing a colonoscopy? And from time to time, patients will come. We have open access colonoscopies, and they're coming too early, or it's not fully indicated, and you will cancel. It's very important to review the procedural indications, risk and benefits. As on the inpatient service, you have to know when to do the colonoscopy and when not to do the colonoscopy. Pay attention for cardiopulmonary complications. Pay attention for cardiopulmonary issues in your patients. Assess the scope position, resting on the bed or resting off of the table. Generally, most of us start with resting on the bed. And develop awareness of your own body position. We'll talk about ergonomics and some of those things a little bit later in the animal labs. Scope insertion, use water immersion, use carbon dioxide, use as little air as possible. Position changes, we mentioned, to get around. Rotating more supine, rotating more prone. Abdominal pressure, and we talked about different areas that are perhaps more high yield because those are the areas that the loops form. Reduce your loops. Theoretically, it's very easy to reduce your loops, pull back and torque. Practically, it's a lot more difficult. This will come with time, but always pay attention of your loops. Always be cognizant that sometimes you're pushing, but the scope isn't advancing. Scope withdrawal, we kind of briefly touched on this. Your views matter. Clean the mucosa very, very well. Be very thorough. Look behind those folds. There's a sort of axiom that, you know, slower is faster. The slower you go, your careful look, you don't have to go back in. You're able to really see everything and have a good high adenomae texturing. Navigate the folds. Use tip deflection. Using your right and left wheel, torque, and then we spoke about retroflexion in the cecum as well as in the rectum. Take your time. Be methodical. And I think that concludes our presentation. Thank you, guys. Any questions? Yes. Any questions? Yes. So you guys being cognizant of cardiopulmonary complications, one of the most common consults that we get at our institution is colorectal cancer screening in preparation for advanced heart failure therapies. And so the average patient has been, you know, off ECMO for four days and has an impella in place and we're asked to do a screening colonoscopy. Is there, like, an official opinion on this? Right. I think you ask everyone here in the audience. We all have those consultations. The – how to put it? It's sort of – so when we talk about cardiopulmonary complications, just, you know, generally, what we don't want to avoid is the patients who are sick who don't have a cardiology clearance or consultation and a risk assessment. You have definitely lots of patients who are quite sick from a cardiac standpoint or even from a pulmonary standpoint who need a procedure, but they're as optimized as possible or cardiology tells you that the risks – the benefits outweigh the risks of doing the procedure. In this case, they're very worried about bleeding. So it's like us, for instance. We're worried about a heart attack or arrhythmia. The cardiologists don't really care. They can fix that. They are worried about bleeding. We don't care because we can fix that. So they're much more nervous about it than us. So a lot of time, it really is a discussion. There is no official sort of position on that. There is no sort of practical guideline necessarily one way or the other. If it is, it's based on expert opinion. In the literature, there are recommendations that can go either way. In general, it is a discussion between you and the cardiology service and your attending. It's tricky. It always is. But once you have cardiology on board, that does make your decision to proceed with a colonoscopy a little bit safer. Any other questions? All right. Thank you, guys. Enjoy lunch.

diagnostic colonoscopy

indications

contraindications

technique

perianal exam

loop formation