Okay, so we can move on to the next topic and that will be thermal therapies, APC. And so generally what we'll use APC, argon plasma coagulation, is when there are small superficial lesions in the stomach, the duodenum, the small intestine and the colon, and it will ablate kind of the surface mucosa. And so that will be with cautery. You'll use a cautery machine and then a pedal. You'll use a pedal and step on that when you want to deliver that coagulation. Is it something you would use for an ulcer bleed? It would not be something that I would use for an ulcer bleed. You know, the modalities that we talked about before the injection and the clips are better for that indication. The APC is just something for various superficial lesions, like an AVM or potentially a GAVE is another indication for APC. Right, there's no collapse of vessel as part of the coagulation. So you're not collapsing and creating an intravascular thrombus using APC. It's literally argon gas that then gets ionized through a tungsten wire in the center of the catheter that then conducts that current across that. It's an inert gas that gets ionized by tungsten. Argon gas gets ionized and then you get cautery delivered through that gas. So it's only a superficial burn. And then once you get that burn, the tissue resistance goes up so you don't really get deeper parts of the tissue. So that's part of the appeal for ablating AVMs or if you're ablating the margin of a polyp is that you're less worried about deep tissue injury when that's part of the appeal of APC versus other thermal therapies. I don't know if we can take a look if we have a gold probe or a heater probe. We do, okay, great. But if you'd like to start with the APC first. Sure, yeah, let's start with the APC and then we can go from there. This is an Irby generator that's set for APC. There's different types of settings. Ultimately different APC settings of stomach or cecum will hinge upon how much gas is delivered per minute, 0.8 liters to 1.2 liters per minute, for example, and how much energy is delivered during energy delivery through the gas. We're in the stomach. The company already has an APC stomach setting which delivers a decent wattage of 30 watts through this catheter that I'll hand to you. So we'll again, go through the gastroscope here, keeping in mind where our device will exit and we don't wanna go too fast with it. So it jumps out. So, like we were saying before, it's a gas that then becomes ionized, and that's what causes that cauterization. So, with this, you don't actually want to have the probe beyond the mucosa. You want the mucosa, you want the probe just a little bit away from the mucosa so that gas can permeate over the mucosa, and then when you cauterize it, that gets, when you press the pedal, that ionizes it and cauterizes it. So, see if we can just do a little bit of cauterization here. And so, you want to get your, you don't want it to be too far out. You want to kind of get a sense of how far the mucosa is away from your probe. And so, you can have, you can be far enough away that you won't be right on the tissue. You know, if there's breathing respirations that make this, that can make this difficult, you want to just be mindful that your probe isn't too close to the mucosa, but you also need to be close enough to where that gas can permeate on the mucosa. And so, then you want to get in position, you want to make sure that your cautery pedals are in a good position that you don't have to, you know, be searching for it, or, you know, that they're really far away, you want them in a comfortable position. You can't see it, but Stephen's foot is on the edge of this pedal in preparation. There's a metal, center metal lip in it, and metal lips on the sides, and he's resting, oh, there you are. He's resting his foot on the edge adjacent to the blue pedal. The clue that it's a blue pedal is usually for coagulative energy delivering, yellow is usually for cutting through tissue, sphincterotomy, polypectomy. And if you can't remember, you can look on your generator, and the only thing that it says pulsed APC or argon plasma coagulation on the blue side, the only pedal that's active here from looking at this device is the blue pedal anyway, so if you press the yellow pedal, this has a safety mechanism, it's not set to deliver any energy anyway, it's only on the blue pedal that it's set to deliver energy. Okay, but the idea here is to be ready so you don't have to be looking down or fumbling with your feet, you know exactly where everything is to deliver energy efficiently without worrying about I'm in perfect position, oh, I lost it. You want to be prepared the entire time to deliver that energy. And that's crucial because a lot of these lesions are in the small intestine where there's a lot of spasm, the small intestine is moving, contracting, and so when you have that opportunity, you have that opening, you want to be able to cauterize at that moment. So, have my foot on the pedal in anticipation of doing the cautery I have a sense, I kind of sometimes just like to kind of see how far that mucosa is away by kind of pushing my probe out, and then I have a sense that I'm close but not too far away, and I just deliver you know a little cautery here. Oh, grounding pad. Keep in mind when you're delivering this energy. There's a fair amount of gas that's also being delivered. At the same time, and that can inflate the GI tract, pretty profoundly. So being aware of how much gas you're delivering especially if you're delivering gas and you're not actually seeing current being delivered, then you'd have to worry that you're just blowing up the GI tract quite a bit. There are rare case reports of even perforation from over distention, over distention, gas distention from APC delivery. And so, you have to have some caution here. Now it's telling you the grounding pad it's green so it's ready to deliver now. So as foot was ready, probe was ready, already except forgot about the grounding. This is a monopolar device so current gets completed through tissue. Okay, so we'll get in position again we'll see how far the mucosa is away, and then come to a position that we're comfortable with, and then deliver. So you can kind of see that that golden brown kind of a, you know, a marshmallow kind of appearance to it. Yeah, that's right. Sorry. So you can kind of see that that gas getting ionized and, you know, it's, you can kind of do large portions of the, of the stomach like this if in lesions such as gave. And so this can be a very useful tool. So it's just kind of quick, you can do quick kind of quick taps or you can if you have a good lineup and there's a lot of mucosa that you need to cauterize then you can do kind of keep it held down and then just kind of slowly move the, you know, move your scope. Part of the reason Stephen's making this look so easy is because he took some time to make sure that distance between the probe and the tissue was correct before just going, going at it. The other thing is that one of the things that he's doing that I think it's important to understand is he's using his left hand for torsion, not just gripping the right hand to torque, although he has his right hand on the endoscope and he has a good mastery of controlling the tip of the endoscope to get it exactly where he wants to go. So he's found a position where a gentle torsion will get it to be where it needs to go. We have a question. Do either of you have a preference on probe type straight fire versus circumferential or lesion specific? Stephen, do you have any experience using the circumferential one? I have used it probably once and it was just in the setting of we had more tissue that we wanted to cauterize, the location of the tissue was in the stomach. So it just seemed like the circumferential works better in that scenario. I think in terms of, you know, what I've used more is just the kind of straight fire and that's usually what I'll go with unless there is a certain scenario in which the circumferential will work. But I think, you know, to answer your question, it's probably lesion specific. So if there is, you know, a lesion that you think would be better served by the circumferential, you know, you could definitely use that. But I think for the most part, I use the straight fire. Does our unit have the circumferential probe? There is one at West Bloomfield. At West Bloomfield, okay. Yeah. I don't, I'm mostly in Detroit. I don't even think that we stock that circumferential one because we so rarely ask for it. But it is also kind of operator dependent, you know, what you prefer using, what you're more comfortable using in any given particular setting. So there's no one right thing to do. And often, you know, spending some time in your own unit, getting comfortable with these devices may make it more clear what you'd prefer in any given scenario. I don't think there's a right answer to that. I think often I use a straight firing quite honestly, because it's what we have and I'm comfortable because I've used it a lot. But that doesn't mean that it's necessarily better than anything else. Yeah. All right. Well, thank you for that question. And so that's, that's APC. You know, general indications are gave, you know, AVMs and throughout the GI tract. And so we'll, we'll move on to another cautery device here. This is the Gold Probe. And so this is for, you know, if you have a bleeding ulcer, you know, if you have an ulcer that has a visible vessel in it, this is a good use for that, where the ulcer is big enough where, you know, the clip won't completely, you know, oppose the sides of the ulcer. And so the clip isn't going to be an effective tissue, you know, avenue, you can try cautery. And so this is as, as well as with the clip, this is used in conjunction with an epinephrine injection for, for treatment of bleeding. And this one has an injector as part of it, which will function also, you could also function partly for injecting drug, but also potentially irrigating fluid after the fact. Some of them have a separate irrigation port, I'm not sure if this one does or not. This is a bipolar device, so it does not require grounding. Energy is delivered between the metal gold contacts of the probe. And because this is a lower voltage energy that's delivered, it's a more kind of localized coagulative burn, not like a cut setting cut current, I think Dr. Almanza gave a really nice talk about that yesterday, yeah. So like he was saying in his, in his talk yesterday, this is something where you have to keep the coagulation on for, you know, a longer amount of time than you would for some of the other modalities. So you see the alternating metal, I don't know if you can see it very well against this background, maybe against the logo, maybe not. It's hard to see, but there are some alternating, thank you, gold contacts here kind of swirling around the tip. So energy is delivered between those two contacts. So if you're delivering energy through this device, try to make sure that there's contacts that are touching the tissue you want to deliver the energy to. I think there's a lot of vessels, ulcer lesions that are better served this than clipping a lot of people fear using the gold probe and thermal therapies in duodenal ulcers, for example, because they're worried about perforation, but for this to be effective, this is really collapsing and thrombosing a vessel. You have to put pressure, either lateral or forward pressure against your lesion to get it to collapse a vessel. And you have to give at least 10 or 15 seconds of continuous current and trust that the way the energy is delivered, you'll be okay. This has an injector as well. I'm not going to, unless you would like me to, I'm not going to use the injector on this as well. We'll just use it as an example of delivering thermal therapy. Yeah. Excuse me. I think getting comfortable with all these modalities during your fellowship is very important. You know, I think at least during my fellowship, people went to clips a lot faster than they sometimes do this, but I think it's a very good modality to treat bleeding and you should become comfortable with it throughout your fellowship. All right. So as it's getting hooked up, um, I've gotten my probe in place and again, you want to have it. It's a balance of how far the probe is out of your scope. And you want to, um, you know, again, positioning, uh, you know, stability and holding the scope, getting it in the correct position is paramount. You know, you don't want to, um, you want to be able to get a location and get yourself in a position to where you can just, you know, push that probe out, step on the pedal and let it's do and let, um, the device do its work. Uh, you know, the one thing is you don't, you don't want to be adjusting while you're, um, using the cautery. That's good. Thank you. All right. So this, this work, what we're trying to figure out on the machine here was, uh, the correct setting. We kept on going into APC. And I think it's because it was set to the, to the APC monopolar setting, the ground pad setting. And once we switched to the bipolar setting, it automatically gave us bipolar probe setting of a bipolar soft coagulation, uh, coagulative effective to, uh, with, uh, not a super high wattage. Uh, so we're not delivering a ton of energy at one time. It's kind of more of a gradual, long-term delivery and, um, slow delivery of low wattage energy will, uh, cause really nice kind of thrombosis and collapse of a vessel, which is part of the reason why this works so well. And I think another reason for this, um, is here is not only to inject, but also to hook up a water pedal to that. And so the idea is you are, um, you put the probe into the tissue, you cauterize, and then you inject some water as you pull out the, um, the probe. All right. So we'll go ahead and, and demonstrate this now. So I'll get in a position here and, um, like we were talking about before, we want to be in a stable position. Um, if we can get one, you know, it's not always so easy with, uh, you know, a bleeding ulcer, but you want to get in a position you want to, uh, like Dr. Proctor was saying, you want to give pressure because you're collapsing that vessel and then applying the cautery. So I'll get in a position here. And then I'm going to push this probe in also kind of give forward pressure. Yeah. Depending on where you're located, your optimal way of delivering pressure might be lateral torsion or dial pressure, uh, rather than for pressure. So it may be circumstantial depending on the lesion and your position on the lesion. But I think this is a very nice demonstration of, of, of where you can clearly see tenting of tissue from that pressure you're applying with it. With a device. And that's either by pushing the scope in or, um, pushing the probe out or a combination of the two. And you just want to, you know, use whatever you can in that situation, depending on the scope position, you know, where the ulcer is, et cetera. So it's, you know, you have to individualize these things for the patient and the specific ulcer. So we have, um, some good, I believe some good positioning here. And as you mentioned, you've already injected epinephrine so that if this, if there's going to be, you know, to minimize the chance of there being immediate bleeding from, uh, from, uh, from a blood vessel in the area. So you often will inject epinephrine first and then apply this. And you have to be selective about where you're applying this to. If it's a, if it's a vessel, that's twice the diameter of this catheter, that might be a, a vessel that's best served by interventional radiology or some other modality. But for the vast majority of lesions, this should be adequate finding a pigmented spot or a visible vessel and making sure you deliver energy directly onto that vessel or that pigmented spot. Yeah. Yeah. That's crucial is just this, this should go on the vessel itself and then forward pressure. And again, it's, you know, uh, longer than you would be used to, uh, applying cautery for other modalities. But with this one, you know, the setting is such that, um, you can apply that pressure safely. I mean, we can all count and you can count at home as well. Uh, as loud as you'd like, we'll count the number of seconds. We'll get to, do you want to get to 10 seconds or 15? Um, you want to get to 15? See why, why not? All right. Let's see what happens. Let's demonstration. So, all right. So, uh, I'm going to apply the cautery. 1, 2, 3, 4, 5, 6, 7. You're insane. 8, 9, 10, 11, 12, 13, 14, 15. All right. That's often how you end up counting. Look, it didn't go. Everyone thought we're going to see a big hole, but it's not right. Just a small perforation. It's okay. We can always have the clips. I will. I will say in all honesty, there are, there are times when I do this and I will do it eight to 10 seconds and then I'll stop and look and I'll say, I think we need more cautery time. And I always feel guilty because I feel like I asked probably not the best thing, but, uh, so, you know, I think in general, 10, 15 seconds, but sometimes it requires more energy than it sometimes requires looking at it again. And saying for this to be effective, we need more cotter. We just have to have more car, but it's low wattage. Uh, and, uh, and, um, delivered in a way where it's not going to be SD, but it's more kind of generally diffused. Yeah, it's very nice. And it's nice. You see the little divot that that's how you know, you did it right. Cause it's clearly forward pressure there and get close to that to show them. It's not, there's not a hole there. Just a nice coagulative effect. It's very well done. Very well. All right. All right. Thanks Joe.

thermal therapies

argon plasma coagulation

gold probe

cauterization

ablating surface mucosa

cautery