The Colorectal Quiz Episode 23: Hirschsprung Disease - The Soiling Patient Part 2 -The Dentate Line and Motility

Hey there listeners, it's Amanda Jensen at Riley Children's. Today I bring to you a special episode specifically talking about Hirschsprung's disease and the soiling patient. And this is part two of a two-part series. With the last episode, we talked about a Hirschsprung's disease patient that was not doing well and actually soiling and what is the potential for bowel control. We specifically talked about the dentate line and looking to see whether or not it was intact and regarding the sphincter, if it was concentric and what is the squeeze. In order to evaluate this patient, they need to be awake and additionally, anal rectal manometry can help you with this evaluation. If the sphincter tone is poor or if the dentate line is inadequate, this patient will need mechanical emptying in the way of malone or retrograde enemas. Again, if you missed this episode, go back to episode 22 to revisit this topic. Today we will move on to specifically talking more in depth about the dentate line and motility. All right, Dr. Lovett, why don't you start us off? Let's talk dentate line, shall we? Let's look at, because this is the other component of continence. Remember, the three components of continence are quality of sphincters, quality of dentate line, and motility. And when it comes to Hirschsprung's disease, there's two sphincters to really be concerned about. One is the external sphincter. Was that preserved? That's the one that patients have control of. And the other is the internal sphincter, which, as you know, from Hirschsprung's disease tends to not relax. They have an absent rare rectal anal inhibitory reflux. However, if they have been overstretched, then both the internal and the external sphincter are problematic. One very typical scenario that we see, let me ask you, what do you think it means if you have a patient that has voluntary bowel movements during the day and has accidents when they go to sleep? So at night they poop, but during the day they have control. What does that mean to you, Hira? What is working and what is not working? So their external sphincters are working and the internal sphincters are not. So when they're sleeping, they relax their external sphincters and that's how they lose the control. That was Dr. Hira Ahmad, the new pediatric surgery junior fellow at Seattle Children's. Yes, and I think that can happen if the dentate line is lost and that can happen with some overstretching also with some preservation of the external sphincter. Mark, can I scare you for a moment? That was Jason Frischer from Cincinnati Children's. Can we talk scientifically for one minute? I know this is crazy, but let's talk about the dentate line. What is it? How do you recognize it? Because we're going to show a number of photographs in a few moments to sort of see, is the dentate line intact or not? But why is that important? What does it mean? What does it signify? And so, you know, dentate line, we use that term dentate line. Some people use the word pectinate line. And it's the transition, right, of how do you recognize it? It's a transition from squamous epithelium to columnar epithelium, right? And so there's a actual color or transition from a gross appearance. But and this happens in the anal canal about two thirds of the way up. But there's also blood supply changes that occur there. So splenic versus systemic blood supply. And then there's also innervation in that area. And I think that's where we think it's key as as anatomic surgeons of why we try to preserve that line is in that area. When I talk to families pre-op and I discuss where we make our incision, I talk about that dentate line in the area where the nerves are located that tell you gas liquid solid. How hard do I need to squeeze? How long do I have to squeeze for? How tight do I have to squeeze is all innervated in that region and preserving that region is key. And so understanding, taking care of patients post-op from Hirschsprung's disease, you need to recognize if that region has been injured in some way that might affect a patient's ability to be continent. Does that sound right? I mean, I'm trying to be. I don't know. I don't know if I am still worthy of this podcast after scientific analysis. Have you heard the word? When's the last time you've heard cuboidal epithelium? I'm going to sign off and you guys just. I actually, if I may add one more thing, I also think that there is a proprioception concept, the stretch and the rectum part, not the anal canal, I think has that capacity, which is why in anorectal malformations, you really got to try to keep the rectum because if the rectum stretches, you can detect that. That's called proprioception. And that's your signal. Uh-oh, stool is accumulating. It's time to exert some authority over my external sphincter, hold the stool in and find a bathroom. And then if your internal sphincter is doing what it's supposed to, it relaxes at the time of the rectal stretch. This is why in ARM patients, in anorectal malformation patients, giving them a stool softener is so problematic because basically they never feel the stretch. They just have loose stool flowing. So they are much better off with bulk, which is then kicked out by a laxative than a stool softener that just slowly oozes out. They'll never have control of that. Such a great point. It is such a, it's such a little nuance, but so important to understand that any child, anorectal malformation, Hirschsprung's disease, spinal conditions, a combination of any of those, their ability to sense stool in their rectum or neorectum region is so sensitive on whether they're successful or not, that that right consistency of the stool or bulk of the stool is very important. And we as clinicians prescribe all different types of medications to manipulate the stool, which also manipulates the stool consistency and bulk. And if we make it too soft or too loose, we're putting a child or a person who is on the teeter of having control or not, and you throw them over that edge and you just won't be successful. That clinical scenario was beautifully illustrated recently by a very good friend of mine, whose name I will not mention to protect his privacy, who traveled and came back to work with traveler's diarrhea. And we asked, he actually missed, he or she, I won't even mention who it is, but asked, took a day off. And then they came back and he said, how are you feeling? And they said, well, I'm not yet farting with confidence. And what that says is so important because loose stool is your enemy. If you have borderline continents, it's your enemy. If you have completely normal continents, right? Loose stool is hard to deal with because you don't know for sure that it's there. We are very dependent on the stretch on the bulk of the stool in the rectum. And then that's when the external sphincter goes into motion and the internal sphincter relaxes. Patients with Hirschsprung's disease with absolutely intact sphincters are dependent on that stretch. Remember, they don't have a rectum. It's been removed. Their sigmoid has now taken over that job. If they have injured sphincters, they're particularly in trouble. All right, let's move on and talk about the dentate line. For those of you listening in the SayCurrent app, this is image number one. Patient is obviously under anesthesia. I have placed Lone Star pins to delineate the dentate line. This is really important to understand this anatomy. And how is the dentate line in this photo? Looks beautiful. Yes. And in fact, this is a trick question because this patient's never had any surgery. This patient is about to get a biopsy to rule out Hirschsprung's disease. And I took this picture of a absolutely, totally normal, never touched dentate line. Again, showing the squamous. This is where you see that change from squamous epithelium to columnar epithelium. And that's it. It's unkeratinized or non-keratinized squamous epithelium going to columnar. And that's that color change that you see. All right. And now we'll turn our attention to image number two. Hira, what do you think of this dentate line? It looks intact to me. Hira, you've had excellent training. Yes, it is perfect. Again, normal. This is actually a patient who has had surgery, who was being evaluated for some soiling. And you can't even tell this patient had surgery. This is a beautiful pull through. Really, really well done. I don't know where the anastomosis is. It's perfectly healed. The dentate line is intact. And in fact, this patient just needed a little bit of Senna to help them stool a little bit better. All right. Now we get into some serious trouble. All right. Turn your attention to image three and the secret app. Now someone took a biopsy, but not sure if you had a biopsy is necessary. Although while you're there, you probably it's worth doing. But clearly this patient's problem is their dentate line is missing. Right. There is no evidence of a dentate line. They've started their dissection too low. We've lost all the value of any anal canal sensation. I do think it's a myth to say that this patient cannot have bowel control. I think this patient can develop bowel control provided their sphincters are working. They will be very sensitive to loose stool. They won't be good at detecting that something is there unless they have bulk. But if they have the right diet and the right stool consistency and sphincters that are intact, we can get this patient through. But it's really challenging if they have a missing dentate line. It's very hard. I mean, it makes sense that they should if the muscle is intact, right? Because this is no different than an anorectal malformation anastomosis. That's right. But it's rectum or colon mucosa to skin. All right. On to image four. Hira, what do you think? It looks like it's partially intact in this patient. So Hira, you're about to go train in a wonderful children's hospital. If I asked you which side of this anoplasty did the fellow do and which side did the faculty member do, what would your answer be? I will always blame the fellow. Very good. You are ready for your fellowship. All right. On to image five. That is a Hirschsprungs patient. I promise you. Yeah. That's unfortunate. Horrific. That is a patient with no dentate line and patchless sphincters. And you clearly see with the skin changes around that, that this patient has really struggled and has been soiling and sitting in pull-ups or a diaper, really causing severe skin irritation. Wait until you see image six. Oh, I'm scared. Oh boy. And there it is. There it is. It does not look pretty. I mean, this is just absolutely the worst. These patients, there are two of them here, show a horrific diaper rash, perineal scoriation related to no dentate line, no intact sphincters. These patients needed temporary stomas. And I think the one on the right needed a permanent stoma. Nowadays, by the way, I think I can make that patient better with this sphincter tightening discussion. All right. So that is the anatomy, anal canal and sphincters that we talked through. Now, let's, I'm going to, I'm going to paint the following picture. We have a scenario with the patient with excellent potential for bowel control. Sphincters and dentate line are intact. And a patient without good potential for bowel control, sphincters and dentate line are problematic. Now the third factor, the motility factor kicks in. All right. And go ahead and turn your attention to image seven, which is the contrast study in the state current app. What is the problem with this colon? Again, I'm going to get to what to do about it, but is that a colon here that moves too slow, too fast? There's transition zone or there's a stricture? Poor Hira. On the spot, like for an hour. Where's the rest of my buddies today? So it definitely doesn't look like the colon that moves too fast. It could potentially be a colon that moves slow. Why do you say that? Why? I mean, you had a thought process. Tell us. Right. So just reading the contrast enema, it doesn't look like there's a lot of postrations in the colon that are causing these potentially you could interpret as like postrations as contractions of the colon. And usually the colon moves too fast. You have a smaller caliber colon with a lot of postrations and not as dilated. When you're concerned about it moving too slow, there's a dilation of the colon. There's lack of postrations. So you could potentially say, I mean, of course we need a motility study to really make the determination. But reading the contrast enema, you could say that the colon is potentially moving too slow. Yes. And then the other thing to consider is, is there a problem with the pull through? But remember, we are talking about soiling. And we specifically made the comment that these patients are not obstructed. We already talked about the obstructed patient. But if you, you need to take a history, you need to say what happens to this patient. And if this patient has soiling, no obstruction, no distension, no enterocolitis and three stools a day, then that's a patient needs management of a slow moving colon. But let's talk about the next slide. All right. And if you're in the State Current app, turn your attention to image eight. The next slide is the same contrast study. But now the scenario is how would you treat the patient? And how would you treat the patient if the sphincters and dentate line are intact? And how would you treat this patient if the sphincters and dentate line are deficient? In both scenarios, patient need a bowel management program. If your sphincters are poor and your dentate line is deficient, probably mechanical, as we mentioned before, with an enema program. If the sphincters and dentate line are intact, we could potentially start with a mechanical and then switch them over to laxative program. I like that. To complete the story, of course, if this was an obstructed patient clinically, then we have to go looking for a cause. And maybe there's a stricture here that's causing the dilation. But our assumption is that this is not an obstructed patient. He's got a little bit of constipation. We have to treat them. We're going to treat them based on their potential for continence. If they have great potential versus no potential or problematic potential. And then keep in mind, which we're going to get to in a little bit, what do we do about the sphincters? What if everything is fine? Dente line intact. Sphincters are intact. He has this image. What about the sphincters? Maybe we need to treat the sphincters. And that's where the Botox session comes up. Let's hold off for one second. And let's talk about the other side of this coin, which is the next slide. If you're in the State Current app, turn your attention to image nine. What is wrong with this colon? Right. So in this one, the colon is decompressed and you see a lot of prostration. So potentially the colon is moving too fast. That's right. Now, if this was a patient that was behaving obstructed, you might say this looks like transition zone pull through. But in this patient actually stooled seven or eight times a day. So this is not a transition zone pull through. This is a good ganglionated pull through. This is not a stricture. There's no maximal dilatation. This is a patient who's moving too fast. And then similar question. If the sphincters and dentate line are intact, how would you treat? If the sphincters are poor and the dentate line is deficient, how would you treat? So I think in both cases, we can start off with constipating diet, add bulking agents, add PPIs. But if the sphincters and dentate lines are not intact or it's deficient, then we may have to start with irrigations or say like small enemas, small volume enemas. Right. These are the harder patients to take care of. And the trick that I use is you have to constipate them. And then if they're able to empty with continence on their own, then great. If they're not, then you have to mechanically help them empty. But it sounds counterintuitive, but at least the way I treat these patients, I constipate them and then I empty them. So whether they can empty on their own versus empty with the need for mechanical emptying to sort of keep it timed and keep that patient mechanically or socially continent sort of depends on their sphincter function, etc. But that's how I sort of explain it to the families. It sounds weird, but we're going to constipate you. And then we have to figure out how to empty you in a time controlled fashion. Yeah, I really like that. I think that's really, really well said. I mean, the bottom line is we have solved the obstruction. The Hirschsprungs is an obstruction problem. Now the tough part is getting them clean. Two separate and independent challenges. Most of them get clean on their own. That's why Hirschsprungs, vast majority of patients have a great, are great success stories. But then we need to know, are they too slow or are they too fast? How do we manipulate their motility? And we need to understand inherently, do they have the mechanisms needed for continence, i.e. their sphincters and their dentate line? All right. And let's go over the treatment of hypermotility. Dr. Levitt, why don't you go through with us image 11 from the State Current app? This is a list of like what to do for the hypermodal patient, how to slow them down. So obviously skin care is vitally important. And a cyanoacrylate based barrier is very helpful. The wound care has become marvelous. The amount of improvements in wound care of perineums and its care of Hirschsprungs disease or any hypermodal patient has dramatically improved over the last four or five years. Proton pump inhibitor is also helpful to reduce the acidity of the stool. And there are some creams like some products that are antacid that you can take orally, liquid that you can put on the skin that reduces the acidity and helps the excoriation. Here you mentioned small volume enemas, which are a very helpful maneuver. Then water soluble fiber, which produces bulk. And there's a whole bunch of fibers. Some of them are water soluble. Some of them are water insoluble. You want the water soluble one that forms bulky stool. Then there's loperamide. Loperamide is very helpful medicine. We try to give that and we go max. We max up based on the patient's weight. And basically that is 0.5 to 0.8 milligrams per kilogram divided daily. The next level of treatment is cholestyramine. And thereafter, we've also used something called iocyamine, which I call Levson, but Levson is the trade name. 0.125 milligrams tab every six hours. And finally, diphenoxylate atropine, which is called Lamodal, which I almost never use because it has some cardiac defects that you don't want those side effects. But this is the armamentarium available to slow down the stool. Have you used tincture of opium at all? Yes, and that's also useful. But again, it's a controlled substance and it's difficult to get prescribed. And then to finalize our conversation, if everything checks out with the pull through and they're still not emptying, don't forget about Botox. We talked about Botox a little bit in the last podcast, but it's just a reminder of the fact that we may need the patient to train and do a better job at controlling their non-relaxing sphincters and not being withholders and adding to the problem. And I think that's a good point, Mark. And we, I think, see it and anecdotally, I want to bring up two things. One, I think Hirschsprung's patients who have a good operation, their sphincters in some patients seem to be like these super strong sphincters. And sometimes they just need a little relaxation to allow for a passage of stool until they learn to that external and internal sphincter to coordinate properly to allow for evacuation. And that's where Botox, I think, comes into play to sort of train those sphincters and also getting maybe some objective data from anorectal manometry to see what the resting pressures are in these patients. They're usually on the higher end of normal. And then just sometimes some patients need that extra relaxation to allow them to go. The other thing we didn't mention today, which I think is very important and probably worth its own podcast, is nutrition in patients with Hirschsprung's disease. I find patients with Hirschsprung's disease are very sensitive to some foods, some patients. Lactose being one of those foods that I find very sensitive, but there are certainly others. And so sometimes paying attention to a patient's diet, whether it be breastfed infants to their diet as they're older, I think it's very important to at least pay attention. Because I find lactose particularly to be very sensitive in some patients. So I don't know others' thoughts on that, but it definitely plays a role. So if you guys had to pick a soiling or an obstructive problem, which one would you pick? None. We have to get it right the first time. And if you don't get it right, you got to use these techniques and this algorithm to figure out what's wrong. Because we could get every patient doing well. They might need help and it might need mechanical evacuations, Botox, etc. But we all should be able to get these patients on the right track. But I will say the hardest group of patients of all the Soilers that we take care of, which include anorectal malformation, Hirschsprung's, functional constipation, and spinal, the worst group, the hardest group is definitely Hirschsprung's. Without question. Because the sphincters are so troublesome. But of that group, the hypermodal are much harder than the hypomodal. But with strategies, you can really get a lot of these patients clean that we're told they could never be clean. If you sort of have your methodology, you know if they have potential for bowel control, and then you manipulate the motility as we've discussed. All right. And that wraps up episode 23. Hirschsprung's disease and the Soiling patient. This is part two of a two-part series. Today we talked about that dentate line and how important it is that it is completely intact. And specifically looking at skin excoriation and how to prevent that. And then lastly, looking at that barium enema and how to tell whether the patient's colon is moving too slow and is hypomodal or is hypermodal and essentially too fast. And how to manage that medically. Thank you for joining us today. Remember, knowledge should be free. Until next time, this is Amanda Jensen from Riley Children's. is a man. I was a man. I was a man. I was a man. I was a man. I was a man. I was a man. I was a man. I was a man. I was a man. I was a man. I was a man. I was a man. Thank you.