So, my name is Adil, I'm one of the second year GI fellows, and I'm trying to put my questions in a form of a clinical scenario here as well. The first one would be a patient who has a partial, say, a perforation, and we suture it. We see the defect. We suture it with endoscopic suturings, the overstitch, or anything else, and this patient's monitored overnight. And the resident gets an x-ray which shows some air under the diaphragm. So, how long does it take carbon dioxide versus air to stay in the peritoneum? Like, should we just monitor this patient, get a KUB in the morning, or should we give them a precise answer that, hey, the air can stay so long, CO2 can stay so long? No, that's a great question. I think it's one of those issues that you face, right? So, you have a perforation, you're spending some time in there insufflating, trying to close it. So, it's going to be expected to have pneumoperitoneum. The patient's going to have some abdominal pain. Those circumstances, you probably, you definitely want to get a colorectal surgeon consultation, be involved, patient antibiotics, MPO, and so forth. But you want to monitor them clinically, right? So, if the abdomen's fine, the patient does not have some signs of peritonitis, you really don't have to do anything. Now, one of the things I've done in my practice nowadays to kind of clarify that question even more is, if I have a perforation, I'll go ahead and close the perforation, especially in the right colon. What I'll do is I'll inject contrast. So, I'll close the perforation, put into the lumen, you know, a couple 60cc syringes of contrast to compress the colon, and then I'll send the patient for CT scan. So, what happens is, they may notice some pneumoperitoneum, a little bit of air, but they won't see, if they don't see any contrast extravasation, I feel very good about the closure. So, even if the patient has pain, which they may have, it already confirms that I closed it endoscopically, so I feel a lot better about that. That's particularly useful for perforations in the right colon, when IR, it's going to be hard for radiology to administer contrast to reach all the way to hepatic flexor cecum. Yes. Thank you. That explains. The amount of CO2 air that you see on the CT scan does not correlate with severity of the perforation, so air alone, we don't worry about it, but if you see fluid leaking, that's when we really worry. And another thing is, after ESD, we know that after ESD, even without perforation, the study has shown that you sometimes see air, so don't jump to do something more invasive just because you see air. We have to look at the patient. And the only comment I'll make is, you know, to your point, first of all, the vast majority of perforations, you're going to close with clips, not suturing. Number two is the vast majority of perforations will never need operative intervention with CO2. So, it's just that key of getting your surgeon involved, but also communicating with the team and understanding we don't need an X-ray, we don't need a CT, and a lot of these patients you're going to send home. You're not even going to admit them. You'll observe them for an hour, and it's your clinical exam, which is critical. And then there's a few of them that will deteriorate, and when they deteriorate, everyone's aware and then you can get imaging or go to the OR, but that's a very rare minority, at least not in the... I'm not talking ESD. I'm talking just EMR. And again, because if you had to do suturing to close something, that's a whole different animal because that's going to take you a while to get the scope down and do all this stuff. But a clip, you can close most things within a minute or two, right? So I think that's a differentiation. I think also the prep quality plays into it, right? And if there's a lot of soilage, again, these are things that you'll really ultimately fall into the bucket of how does the patient clinically look. If I could just add, the pneumoperitoneum that sometimes shows up, incidentally, just as a result of having an ESD, can sometimes lead you down a path on the inpatient service where now the colorectal surgery team is involved. And I would say in those cases, it is really critical for you to be communicating directly with the colorectal surgery attending so that this patient does not inadvertently get taken to the operating room for some perceived perforation or free air that you know is not clinically relevant or there. And so when you're in these situations and you do decide to get surgical backup just in case you're not really sure how things are going to go, please stay very closely involved because most of these ultimately do not require surgery. Thank you. Question back? Do you guys ever monitor a CT scan to see if there's any perforations? Myself, I just observe clinically. I think, how about you? Yeah, I don't do it routinely. So the CT scan example I was giving is, you know, when you have a large perforation, right, and you're closing it up and you're still unsure, you know, is this an adequate closure or not, that's when doing it in real time, I find it more helpful than having radiology do it at a later point because they do it and then they're going to say, well, I don't see the contrast reaching the point of interest. So now you're stuck with an image that didn't really help. There's some air outside. So if I have any question whether it was closed well or not, I'll just inject the contrast myself and send the patient to CT right then. If not, I just follow the patient clinically and don't image. In the lumen, yeah. One of the first videos that you showed was a big polyp and there was a central depression, right, and you asked how would you approach it? Would you do it now or later? I guess I'm into my first year as an attending, but like identifying exactly like is it 2C, is it pseudo-depressed versus this is, as Dr. Othman were mentioning, it's the lesion overall is raised and it's not actually going in submucosa. How do you, like is there a specific tips to follow to identify depth of the lesion and how to approach it like inject and see if it lifts versus just leave it for ESD or refer it to a surgeon? Yeah, I mean from at least my perspective and I'll see how the ESD folks take it, you know, I think having the understanding that was pointed out, right, most of these are pretty clear. I think a true central depression is something that we, you know, you see invagination below that. I mean it is below the level of mucosa where it's pretty obvious. This was not a central depression and so, you know, again it's a scenario that you may not tackle index colonoscopy, but I think when you're coming back for that, in that scenario, if your choice is standard EMR, you're going to go with injection and that's going to tell you. And there's no harm getting a non-lifting sign and stopping and saying, hey, I'm going to talk to these guys or I'm going to send it to surgery at that point. A lot of times it does take that to figure it out. I think we all can talk about all these classifications to death, but the clinical practicality of it is there's going to be scenarios where you're going to have to use some intervention to further clarify if you're correct or not. So just to add to that same point that Sri is making, and kind of like what I showed on the videos, right, a lot of the lesions that we looked at, we said, oh, you know, maybe that's a J-net type 2B, et cetera, the tubular adenoma that I showed you, it looked kind of more ominous. So it just tells us, you know, in clinical real-world practice, we're not very good at endoscopic assessment as compared to our Japanese counterparts. So you're going to run to these scenarios all the time. So the main thing, the way I look at it is, like, if you look at something and you're unsure, you think there may be invasion, then don't tackle it. Don't try to start resecting it if you are in doubt. I agree, you can try to inject and see if it lifts, but do not inject a viscous solution. So that's something I've been seeing a lot. People inject and they'll say, I inject a rice gel, it doesn't lift. Let me send it away. So all these viscous solutions cause a lot of fibrosis and make subsequent resection difficult. If it's something you think, you know, okay, I'm not sure, but I still think I can remove it and block, you lift and it lifts, great. But if you're not sure, then, you know, it's always good to maybe show the pictures to a colleague and take good pictures and then share it. And just one follow-up question. Would you inject right in the center of, for example, if there's a depression or at the periphery, where do you prefer, if you're trying to identify with a saline injection, I guess? I think you have to be, and there's probably many different ways we do this. I think classically in those, you know, I find injecting with an lesion is something that's predominantly we do for, you know, the sessile serrated lesions. I think it's a great method. I think in these bulky adenomas, it's something you can do if you're really struggling. Once you get into the bulky portion of the polyp, you're going to get some bleeding and it can make the situation tricky. But I think if you start with a typical injection, however you feel comfortable and you're not raising that portion, you may have to attack it directly. Do you biopsy those? I'm sorry. I think we have the same question. If you have done a thorough assessment of the lesion and you're pretty certain that it's a benign adenoma or sessile serrated polyp, then I wouldn't even biopsy it. Right? I would think the only reason would be if you're concerned about submucosal invasion or you're unclear. Otherwise, you know, if you see a benign polyp, leave it alone. I guess I have one other question. Is there, as you're assessing these polyps and you see, say you find one on a screening colonoscopy that you think that you may be able to take off, but it may be centrally depressed, injecting it with saline isn't going to hurt anything for a future resection generally. Whereas methylene blue can also give you a tissue reaction, I think less so with indigo carmine, but a saline injection is sort of no harm, no foul in my mind, and it kind of tells you whether or not it's going to lift so that when you're ready to resect it on a future day, you'll kind of know what you're getting into. My thought, not trying to be disagree, if you are not going to be doing the subsequent resection, better not to do anything with it. Not inject and document non-lifting or do something on it, like snare. Use snare to do big biopsy, don't do that. So, or tattoo close to it, like we see a lot of tattoo today at the base of the resection. So, the non-lifting is not very accurate to predict some ecosystem invasion, because it can be benign fibrosis. So, if you're not going to be doing it, document it. But if you will be doing it, you can do it, you can test it. But in general, I don't find it very helpful. What is the other? Yes. Yes. Yeah, I agree. If you're not going to be treating the lesion, I would generally leave it alone unless you're concerned about cancer, then take a biopsy. And I wouldn't biopsy it extensively. I would biopsy the highest risk areas. Let's do one more question just so we can get a break. We'll get one here. For the pre-cut EMR technique, what sort of ESU settings are you using? Like, for example, if you're using like a dual knife or just a snare tip? I like using more of a cut mode, like a blended cut mode, endo-cut, higher endo-cut cue. And mainly just because it causes a little bit less coagulation when you're cutting that mucosal incision. So, there's a little bit less of that widening effect that you see with a coag effect. So, I prefer using that. All right. Well, thanks, everybody. Save some questions for the hands-on session and enjoy some coffee. Thank you.

partial perforation

endoscopic suturing

air under the diaphragm

colorectal surgeon

CT scans