The management of laryngotracheal stenosis has really changed over the last 30 to 40 years with a resurgence of endoscopic dilation and adjunct procedures. But questions like when to dilate versus proceeding with an open airway procedure, well, those are best left to the experts. And so you guessed it. Today, we are going to talk to an airway expert to review the management of laryngotracheal stenosis. And so we're just going to stick to airway stenosis here. We're not going to talk about things like laryngeal clefts or tracheal pouches or anything else of that. We're talking about stenosis. That's Dr. Michael Rudder. He's an otolaryngologist and the director of the Aerodigestive Center at Cincinnati Children's Hospital Medical Center. He is going to walk us through the important principles of endoscopic and open airway management for patients with airway stenosis. Stick around. This is the Stay Current podcast. It may be high-waisted jeans or chunky round glasses, but everything comes back into style eventually. And surgical procedures, well, they're no different. When it comes to airway surgery, endoscopic surgery is really coming back to the forefront. Prior to the 1970s, endoscopic surgery using bougie dilation was the mainstay of airway stenosis management, but it wasn't without complications. You had a stenosis, you put through a small dilator, cat tail dilator, a bougie, a endotracheal tube, and then you put a slightly bigger one through, and then a bigger one through, and you slowly stretch up the stenosis. A lot of shear forces, quite a lot of mucosal damage. And so this wasn't enormously successful, but it was the best that we had for a long time. The development of open airway surgery in the 1970s allowed for costocartilage grafts and laryngotracheal reconstruction. But now, in the 21st century, endoscopic surgery is back in vogue. And now we've seen the wheel turn. In the 21st century, we're seeing a resurgence of interest in endoscopic airway surgery, and this often complements open surgery. Some patients still need the open airway operations, and deciding who to offer what operation, that's the first step. The question is not so much when you should go open, but when you should not go endoscopic. First, consider the airway to be a cartilaginous exoskeleton, creating the laryngeal complex framework. Endoscopic dilation, well, it can't help with underlying irregularities to that exoskeleton. And if you've got a problem with that exoskeleton, with that framework, you probably shouldn't balloon dilate. So you shouldn't balloon dilate complete tracheal rings, so you might rupture them. If you balloon dilate tracheal malaysia, you will achieve nothing. It's not useful to balloon dilate a tracheal A-frame deformity or an elliptical cricoid, because you've got a framework problem. Endoluminal dilation is best for patients with an intraluminal scar and an intact framework. But even in the best selected patients, there are still advantages and disadvantages to consider. Balloon dilation has advantages and disadvantages. The advantage, all of the dilation is radial. There are no shear forces involved. You can deliver precise, high pressure dilation at low risk, as long as you choose the right size balloon. Unfortunately, these balloons are single use, and that means, well, they can get pretty expensive. Plus, when filling the balloon to exert enough pressure to stretch the scar tissue, it can get a little hard to control. And they're also slippery. The industry term is watermelon seeding. If you squeeze a watermelon seed, it can shoot away from you or shoot towards you, and balloon dilators can do the same thing. When planning to endoscopically dilate a patient, there are a few key procedural steps to keep in mind. And so the technique that we use is to endoscopically evaluate the stenosis. Next, good communication with the anesthesia provider? Well, that's critical. We have to ensure pre-oxygenation is adequate prior to occluding the airway. Then we can begin the dilation. Then make sure they're adequately anesthetized a burst of propofol and have the balloon centered so that the middle of the balloon is at the middle of the stenosis. You then inflate the balloon to the rated burst pressure, having chosen the appropriate diameter, and we hold pressure for two minutes or until the oxygen saturations drop to 90%, whichever happens first. Two minutes? Well, this just sounds like a pimp question waiting to happen. In my experience, specific timeframes in surgery are either attending preference or there's physics involved. In Dr. Rutter's case, I feel some physics coming on. Okay, I'm ready. The reason for the two minutes is if you dilate a balloon on a bench, it goes to pressure and stays there. If you dilate it in a stenosis, you keep having to add water to the syringe pump as the pressure keeps dropping for about 90 seconds as the fibrous tissue is stretched open. Actually, that wasn't so bad. All right, I don't need my calculator after all. After the two minutes, we remove the balloon and inspect the airway. And in a patient with significant pre-procedural stenosis, the improvement can be striking. And so we dilated her with a five millimeter balloon. She was unstable, so it was only up for 30 seconds. And that was enough to give us control of the airway. So this is the same girl. And you can see the marked difference immediately afterwards. Dr. Some patients have a complete and sustained improvement after a single dilation. But for those that require a return trip to the operating room for a second dilation, adjunctive scar removing procedures can be beneficial. Dr. It's premature baby. She's been dilated with a bougie before. She's still got a complex subglottic and posterior subglottic scar. And she's quite symptomatic. She sizes of a 3-0 endotracheal tube. And in this case, we're going to divide some of the scar tissue, inject some steroid, balloon dilator. The instrumentation for endoscopic surgery is fairly specialized, especially for the small pediatric airways. Dr. These two tools are very useful. So typically we will inject some Kenalog with the orotracheal injector set. We then divide the scar bands, typically in a Mercedes-Star incision, with a blitzer knife. When making incisions in the airway, Dr. Rudder has a unique technique. The technique I like to do is to place it with the point away from the airway, get it into the stenosis, and then turn it 180 degrees and cut towards the lumen. You get a much better result. Airway stenosis can happen at multiple levels, either in the larynx or in the trachea. The good news is that endoscopic dilation works regardless of the location. If you can do it in the larynx, you can do it in the trachea. So this is a boy referred to us at six months of age with an acquired tracheal stenosis from intubation. He's extremely symptomatic. He's been referred for a slide tracheoplasty on cardiac bypass. Instead, we divided the scar band and balloon dilated its airway on a single occasion, and he was asymptomatic at 18-month follow-up, as you can see below. From what I'm hearing, balloon dilation seems like the obvious answer for a lot of patients. At Cincinnati Children's Hospital, we've been doing endoscopic dilations for about 20 years, and we've dilated thousands of patients. But scaling to other institutions, well, that presents a few problems. We're really lacking guidelines in terms of technique and in terms of patient selection. And this is what we don't know. We don't know what size balloon to select. We don't know how much pressure is appropriate to put in that balloon. We don't know how long to leave it inflated, when to repeat it, how often to repeat it, who we shouldn't dilate, and when to use adjunctive procedures. When you have a lot of important questions, well, you better get working on some big answers. And at Cincinnati Children's Hospital, we're working to develop these guidelines with the help of some animal models. Using all the available data, a protocol has been developed to standardize the endoscopic approach. The protocol for dilation, we usually dilate three or four times at seven to ten day intervals for established scar. If patients are going back for a second dilation, that's for the adjunctive procedures can really come in handy. We, on the second dilation, may inject Kenalog, may divide some scar tissue, may increase the balloon size. We may consider nebulizing cipridex if there are significant raw areas after the dilation. And if after five dilations, you are not winning, you should take a step back and think, should I be doing something else? As we are learning, not every patient is the ideal candidate for balloon dilation. So when considering the best strategy, patient selection is really critical. The ideal candidate, thin scar, young scar. And if it's something that's a little thicker or quite established, that's when you may want to think about adjunctive procedures, scar division, steroid injection, for example. When selecting the balloon for dilation, size really matters. So Dr. Rudder went about developing guidelines for which size balloon to use in which child. We tried to develop guidelines based on this. And so the formula I used was you take the outer diameter of an age-appropriate and tracheal tube. You add one millimeter for luck for the larynx and two millimeters for luck for the trachea. Wait, what? Okay, I'm just going to say what we are all thinking. Dr. Rudder, is there an app for that? So we actually came up with an app. This is free. I strongly advise that if you have any interest in airway surgery, you download it, and it will help you choose the right size balloon so you minimize risk. Whew, well that's a relief because after selecting the proper balloon size, the next step is correct balloon placement. Bella tips the stenosis. And then we place a balloon dilator, inflate it to the rate of burst pressure. Bella tips the stenosis. Okay, so just to recap. In patients with an intact laryngeal tracheal exoskeleton with fresher thin webs, endoscopic dilation works pretty well. But if there's thick and fixed scar, endoscopic dilation may need to be coupled with adjuvant procedures. And you may need to consider an open procedure if sequential dilations just aren't successful. Everyone can be an airway surgeon, and if you choose the right size balloon, the risk is extraordinarily low. Balloon dilation certainly seems to have leveled the playing field. But there are cases where balloon dilation just isn't enough. Say for posterior glottic stenosis, greater than grade three posterior subglottic stenosis, or bilateral vocal cord paralysis. So let's see what Dr. Rudder suggests for those patients. Dr. And the key here is you've got to get exposure. So you need an easily exposed larynx. It's easier to do these procedures in a patient with a tracheotomy, but it's not required. As long as you can keep the child spontaneously breathing while under anesthesia. You start off harvesting the rib, then you expose the larynx, go and put in vocal cord spreaders, divide the posterior cricoid. I quite like to use a sickle knife to do that and micro scissors. In that small space, it's not easy to place the cartilage graft with instrumentation alone. And so Dr. Rudder, he's developed an innovative approach. Dr. Once you've divided the cricoid, and it will pop open, and you may have to divide the inter-arytenoid muscle as well. You can see the cut edges of the cartilage. Then you're going to place your cartilage graft. And these are difficult to place. I actually quite like to place a balloon anterior. And as you inflate the balloon, it pushes the graft into place. Once you get the graft placed appropriately, it needs to be anchored under the cut edges of the cricoid to ensure it stays in the right place. Dr. It's a lot of force you have to use to get these popped under the cricoid, cut edges of the cricoid. For minor laryngeal webs, an endoscopic repair is feasible. These are great for minor webs or acquired webs. And you don't necessarily need a tracheotomy tube. So we've suspended, we're dividing the scar tissue with a sickle knife, and you've now got one raw surface against another raw surface. So you need to let those mucosalize or they will re-adhere. Dr. Leaving raw mucosa exposed can potentially lead to adherence of the opposing sides. So a keel needs to be placed. And as you can imagine, in a small pediatric sized airway, this is no easy feat. Dr. So on the left, we've put a keith needle into the airway, threaded it through the piece of silastic, and we're then taking the needle out again, using a hollow angiocath as a guide, Dr. And then placing the actual silicon in place is surprisingly difficult. Dr. After you're able to get the keel into place, it allows the tissue to re-mucosalize without re-adherence or risk of re-stenosis from scar tissue. The results, they're pretty amazing. Dr. This is the same girl, six weeks later, she had the keel in for 10 days, Dr. And you can see a much better result. Thanks for joining our episode on laryngotracheal stenosis and all the ways endoscopic surgery has come back into style. If you liked today's episode, be sure to follow us on social media, check out our YouTube channel, our Facebook, and our Twitter. Please leave us a comment wherever you listen to your podcasts. Until next time, I'm Brittany, and remember, knowledge should be free. A focus on collaboration. Aerodigestive disease is a team sport. It involves ENT, pediatric surgery, GI, pulmonary, and everyone in between. You can learn more about that at the Quad Conference.
