Dr. Benjamin Zendejas-Mummert - EAT Center Updates

All right. Good morning, everyone, and welcome to Grand Rounds. It's my pleasure to introduce Dr. Benjamin's and Dejas. He was born in Mexico City and received his medical degree from University Dodd, Autonomia de Guadalajara Medical School, followed by a master of science and clinical and translational science activities from Mayo Graduate School. He completed his general surgery residency at Mayo Clinic Rochester and his pediatric surgery fellowship here at Boston Children's. He then stayed on his faculty and is an assistant professor of surgery at Harvard Medical School, with a particular clinical interest in a sapigil atreasia, tracheumalatia and thyroid and parathyroid disorders. He'll be giving an update on each center research, including the use of indesigning green or ICG spy-5 fluorescence imaging to assess a sapigil and asthmotic perfusion and the use of intraoperative recurrent laryngeal nerve monitoring. Dr. Sunday has, thank you for being here and for sharing your work with us today. Thanks, Hester. We're going to dive in today to our dirty laundry pretty much. And this is, I think, the best way to start improving on these issues, right? We're going to talk about poor and asthmotic outcomes and recurrent laryngeal injuries, recurrent laryngeal nerve injuries, and what we're doing to improve on these. But poor and asthmotic outcome for us can define us pretty much a leak, anything that leaks from our inastomosis or refractory stricter. We have a really good endoscopic GI team that has phenomenal skills and can save many of these stricters within the scopic therapy. But there's some that are still refractory to advanced and scopic therapy, dilations and incisional therapy, steroids, stents, you name it, some still need a repeat operation. And so these are what we are considering, a poor and asthmotic outcome. And unfortunately, because of the patient population we have, we have a fair share of these that we're actively doing things to improve on this. The first thing is to try to understand where can we improve on these elements? We can talk about technical refinements all day long. And we've gone better at this. We've definitely find ways to make a better an asthmosis, we often mention with better blood flow. And that is certainly a big component of things. Another big component of things is also choosing the best patient procedure match for these patients. There's not a, unfortunately, there's not a best choice often for these kids. And we have to define what these best patient procedure selection are. And oftentimes we're left with trying to design an operation for a child. We can also improve with our judgment and tropical ones who are faced with a particular situation. What can we do differently from a judgment standpoint to get the better care for these kids? So in the words of the Almighty Emeritus Professor Dr. Jennings, we truly have to in order to improve on these elements, we have to understand the problem. We've spent more time trying to dissect what is going wrong so that we can find a solution for that problem. And this is what brings us to today. So when we talk about a poor and asthmatic outcome, if you try to separate the elements that go into an asthmosis healing, we can talk about tissue perfusion. It all happened at the level of micro circulation. It also attention affects this. The tissue quality, how much infection inflammation there is in that tissue. And what's the nutritional status of the child? And we all know that these do not occur in isolation, tissue perfusion, and tension are deeply interrelated. If there's increased tension, there's going to be less perfusion. Same thing, nutrition affects tissue quality. And I can guarantee also that nutrition affects micro circulation and tension can affect tissue quality and they all are interrelated. So although they're all related, we want to try to dissect them out to understand each one. If we look about perfusion and blood flow to the esophage, it's very unique. We know from our anatomy classes that has a segmental blood supply. However, when we operate the esophage, we often have to divide a lot of the segmental blood supply in order to mobilize. And so that is the least of our available options for the most part. We rely heavily on this robust submucosal vascular network that you see here in this slide where you have in the submucosum, these very robust blood vessels. And we're going to be talking a lot about that today. Esophagus is different than other GI organs in the fact that it lacks a mezzanterium, it lacks the serosa, and it has a limited length. We don't have excess esophagus that trim a little more and a little more to get better tissue. So these are all challenges and things that take into account when talking about blood flow of these esophage. Now, there are tissue perfusion assessments that are very rudimentary. You know, there's a very fancy in advance, everything from poking it and cutting it to making it bleed. That's one of them. We can also visually inspect it and touch it and see how it feels. And sometimes it's obvious what's dead and what isn't. Not always though. And so this is when some technology can help anything from the classic woods lamp and it's what flourishing to oops, oops to the newer technologies that rely on in the signing green with this five five technology. This is some of the elements we're going to be talking about today. So the challenges with with tissue perfusion assessments is they're still subjective. They look really cool, but they're very experienced and an operator dependent. There really isn't common language of terminology. There isn't a book that says, oh, this is good. This is bad. The company's put out the technology and it's sort of up to us to interpret the results in a way. Spit and if you think about it, it's really really easy to see the extremes. What is really poor versus good perfusion, you know, if it's like totally black, then instead if it's totally bright. Florescence, then it's really good, but most and most of most are most tissues that we assess are not in the extremes. They're in the middle ground. And it's really hard to discern this sort of middle ground. This is where we want to try to improve on. Same thing, we all we're used to numbers and we used to data and metrics. Fortunately, a lot of these software entities don't come with numbers. Don't come with objective metrics. Some do and they're often costly or come with post processing software. So it's not available immediately in real time. So there's some limitations with that as well. So for those of you who've never used this and don't know how it works, this is the gist of it. Essentially, you inject substance in this case in the signing green, which is a floor floor. And the mirror for red camera captures that assessment. And with the special image processing can give you a sort of like an angiogram of that tissue. Then if there is a post processing software to get quantitative metrics that gets done sort of either in real time or later with processing software. Or you can get fancy graphs that show you the time to maximal fluorescence and the maximum intensity, etc. This is an example of a perfusion assessment of the soft joan estimates, different color modes. That's what you were seeing at the beginning. And this is a perfusion assessment. You see the lungs light up first and then the esophagus lights up. And this is actually very good assessment. You see the the the esophics appear for the most part well vascularized. But now let's try to understand what are those elements that go into that assessment in order to do so. We set a project to try to first define what are these qualitative perfusion features? What is the language? What is the terminology that we need to be talking about when developing or discussing this? With that we can mind we want to develop a scoring system that could help us predict an asthmotic outcome so we can act on it or tailor treatment based on that. We had a cohort of patients to start using this around September of 2019. We stopped the data collection around January of 2021. We have 74 patients, 77 is up to you and estimate those are repairs. We have for the purpose of the assessment we excluded 22 patients because they have poor quality videos or they just weren't recorded or the stereo system broke down etc. Which never happens by the way of course. But the outcome measure was poor and asthmotic outcome when we define that at the beginning rate, which is any leak or refractory structure. Essentially something that needs to be in this topic therapy or takes an inordinate amount of dilations in the first year to improve. We also wanted to capture the changes in a disruptive decision making that occurred from the use of in the sign-angry and spy-fight assessments. We really went ahead and spy-fighted everything to try to understand how this works and how the perfusion qualities affect the tissue that we're working on. We really spy-fighted everything. It was really informative. You'd be surprised how well coffee looks under a sign-angry. But anyway, so if you look at these features, the first thing that came out of our attention was the brightness. That's sort of like the first intuitive thing that you see. Sorry guys, let's restart it. I don't know. There we go. We get back to where I was. Switching my settings. Good there. So the brightness, right? So this is the intensity. And define this is much intuitively would be the strength of the perfusion. How much actual blood flow does that look? And you see there's all different types of shades of intensity. You have some that are very homogeneous between the upper and the lower and the pretty bright. They compare others and this is kind of poor compared to the lower one which is pretty bright. Others that are sort of weaker than this one, but very homogeneous. So how do you actually classify these? And then we struggle a little bit about this. On the other hand, you have some that are extremely bright like the dejunum. This is their dejunum position. And because it has a supercharged extra blood flow, its extremely bright has a normed amount of blood flow. So we had to take all these issues into account. But I just wanted to show you the variation and the variability that we can encounter. Another feature that we define was what we call extent of hyper perfusion. What are these dark areas? This area is a lack of blood flow essentially. And you have some areas that are segmental. Like this one over here, you have this big triangle at the level of an estimosis that is totally black. There's no blood flow. You have these other ones that are sort of patchy and have different, almost like fingerprints on the estimosis. Or on the esophageal tissue that aren't as bright as the rest. So that's called patchy areas of hyper perfusion. And you have others that are totally global. Like for example, this one in the middle, this lower esophagus has no blood flow there. So that was very concerning. And so they are what we consider global areas of hyper perfusion, segmental and patchy the most part. Now, talking about speed of perfusion. And this actually has to do a lot with blood flow and the blood pressure at the moment as well, we think. But also that I think the perfusion of the lower the microcirculation. So for example, if you look at this assessment here, you will see that the first thing to light up is the lung. We switch the modes to see this better in the black and white. And the esophagus is right here. You see how the gradually slowly comes up to an estimosis. It's not immediate. It actually takes a little while to get up there. And it's still that nestimosis still looks quite dark. Compare that with this other video in where light up the lung. And then you see a lot brighter. And it gets to the nestimosis a lot quicker. Right? And so even just subjectively that looked a lot faster. How do we quantify that? So the things that we're working on. Now, for example, compare that with this. This is a de juno-interestsition. And look at the speed of this. And so same thing here. You'll see that we're waiting for the diet to come in. And then. You see the lung start to line up. And then awesome. You see this thing. You know, light up like Christmas tree. And it's beautiful. And that you see the vast difference between the esophagus and the profusional esophagus coming from the cervical portion. And the it's juxtaposition extremely bright. And the esophagus takes a little more time so they each have different speeds of profusion. Right? It's not just single speed of profusion for the entire nestimosis. There's another feature that was very interesting that we added toward not at the very beginning that we started noticing that a lot of these assessments, you can actually see the submutechose blood vessels. This is what we consider the arborization or the vessel branching. And it's really interesting to see how a lot of this was also the technique of the focusing of the camera and be able to find these. But some of these have really nicely well defined submutechose blood vessels. And often those were the ones that had better profusion features. The other feature that we defined and looked at was the width of the sutral line of the darkness. I like to call it as almost like the penumbra zone or the hyper profusion zone. So some are really thin. Almost you see no blackness. You see this an estimosis over here has a very thin sutral line. This would be what we consider expected sutral line width. This one has a little wider sutral line with it. It's asymmetric. You have a little blackness over here and it's a little wider. And so this is probably double and expected. Now there are others that look even more on the concern inside. You have this one that probably was more than greater than double the expected. And others that are totally black for a few centimeters. Those are a lot scary. But essentially you see this different patterns of width of this line of hyper profusion up below the nastimosis. I think it's critical as well. We'll show you why that is the case. So we've worked to all these features that we just talked about. We work to develop a scoring card that we used to rate these anastomosis. And you can see here there's a score for each pouch or each segment of the esophagus. And then there's a few of these features that are judged the anastomosis as a unit, the entire unit. And it's fairly straightforward to use once you've used it a couple times. Now you may find the surprising that we actually had four of us, the four surgeons in the group, get together and assess 51 videos. In a blinded fashion, we didn't know which of who the patient was or who, what the score of our other colleagues had been. And remarkably we had to my surprise very good agreement between us. This is interclass correlation coefficients and essentially a coefficient of one would be perfect agreement. So they have interrater so between raiders of point three is actually very good in a scoring system that's so subjective as this one. And also they have so many elements in it. And then I rated these videos the second time several weeks apart blinded for my initial assessment. And the interrater reliability of that was also very good. So both within raider and between raiders, the agreement was very robust. The cohort will talk a little bit about co-op is I think it's very important. This is a very complex patient population as you can see here. Mostly young kids that have a great proportion of them were long gap. And then we had a lot of them were underwent the focal process. Another quarter was a stricture section. And it's not just regular run of the meal newborn type Cs. We did have some some newborn type C E a patients that were in this cohort just to have the variety of patients. But it's mostly complex. You can see 82% had a prior test operation. So a very complex patient population. We had about a medium follow up at the time of January that we did the cutoff about 5.1 months in this patient population arranged from two months to a little more than a year. And in that timing we had 20% rate of poor and astamatic outcome. 11 of them at eight leaks. And we have five refractory strictures. There's a little bit of overlap there because some leaks went on to be refractory strictures. So we had a C from this table of graft that the perfusion scores varied significantly between those patients that had a poor and astamatic outcome and those who did not. So on average those who did not have a poor and astamatic outcome was a score of 14 with a range that ranges 0 to 19. 19 would be the best possible perfusion score. And those we had a poor and astamatic outcome was about 10.6. Now in terms of statistics, the area under the curve is 0.77 which is pretty good. And if we put a cutoff score of 13 that has a reasonable sensitivity specificity to predict the poor and astamatic outcome. It gets a little bit better than that because we're so far we've only talked about perfusion. So we'll talk a little bit about the other features. We did look specifically at each of the features. This is a pretty busy slide. I'm sorry for that. But I just want you to pay attention to the ones in yellow. And out of all the features that we were looking at, the ones that appeared to be the most predictive or strongest associations with the outcome were these three, the extent of hyper perfusion, whether it was segmental or global or patchy or a combination of the rough. The width of the sutra line and whether there was vessel or barrication present or not. So those three features appeared to be strongest predictive. And we use those later in the scoring system. But as we're talking at the beginning of this presentation that perfusion is not the only feature that affects an astamatic outcome, right? Tissue quality and tension was another couple of things we talked about. So rescue folk or patients, we had a total of eight of them, prior, kids who had a prior traction strategy. And so that represented about 15% of our patient population, mobile half of those at a poor and astamatic outcome. So rescue folkers had a 50% chance of a poor and astamatic outcome that speaks to tissue quality and certain degree. Now, tension is also very strongly associated with this mild modern insulator. We classified this based on how hard it was to get the ins together. Did we have to use peanuts and flex the patient and crunch them? And so we had definitions of what tension would be based on that. And so you can see that about 20% 18% of our patient population was severe tension. Though there was sort of even we split with the mild and moderate, but that about if you have severe an astamatic tension, there's a 50% chance of a poor and astamatic outcome. So again, tissue quality tension and perfusion appear to be critical factors for an astamacute. And there's sort of intuitive right, but up until now there hadn't been any data for that. Now, when we look at this with those features, we develop a scoring system that includes all these features. And so this is a scoring system up above. So if you have a rescue folk or with severe an astamatic tension, if it has global or segmental hyper perfusion, if there's absence of our barrication or the suture line is twice the expected width, those are all the negative features. So the greater the score and this scoring system that includes all these features, the worst outcome there is. So you see how the probability of poor an astamatic outcome increases exponentially pretty much with an increase in score. We determined the cutoff score of greater than two. Anything greater than two is concerning because you're now you're getting into the chance of a poor an astamatic outcome of greater than 10%. And the area under the curve for this model was significantly better than the model with just the perfusion alone. You see it was like it used to be 0.77 and this one up to 0.85. When you're talking about diagnostic accuracy, this is really good. Anything close to above seven and point seven is really good. So anything about point eight is it's really pretty much unheard of for the most part. So this is a very sensitive and specific way to look at this. So what are we going to do with this information? Right. Obviously this allows us to do better patient family and counseling. It also allows us to tailor our postoperative management to the risk predictive profile of these patients in order to decide how many days do we paralyze them? Do we need any position and precautions? When do we get these officers and how quickly do we get the chest about? Do we have to be more aggressive with the air and scouting surveillance? So have some data behind that to guide some of these decisions that for the most part are some of the subjective. Now talk we haven't talked about the other big element of this. Not necessarily the risk prediction, but the bit changes them in tropative decision making. This has been one of the most sort of fun features about this where this is giving an example. I have a few examples to show you how things have changed in the OR based on these assessments. This is one to do an order position that we did. And on the outside look great. We were very happy with the nest of most. We were pan ourselves in the back and and also we do the spy fight system and and also in this. You can see clearly that the upper 10 centimeters or 5 centimeters of this and it was totally poor profused. This looked great, but what's going on here? Really concerning. And so also we look up the anesthesia monitor and we know that the patient's blood pressure is 40 over 20. And so we were like, OK, well that has to change and we talk to our anesthesia team. They give a little extra volume, a little extra blood pressure support. And gradually starts getting better and better. And we just sort of waited a little bit longer and we checked. And it also in the blood flow starts to get to the very top. And now we have an observation that the blood pressure affects the perfusion of this and so this is where some of this for some of our to do not enter position patients. We've fine tune the blood pressure management goals for postoperative care based on what we see intraoperatively are our better perfusion for that anastomosis. So that way we can come up with with target meaner to your pressure goals for that patient in the postoperative care based on how that profusion looks. So that was really informative. Now a lot of this also begin with this particular patient where we had a patient with a caustic injury and had a severe stricture of the soft. You can see here the stricture. We were able to operate this patient and perform a stricture section or primary and estomosis. Unfortunately when we did the spy by assessment this is kind of like a crappy video just based on the quality of the video bit. I'm going to sort of highlight the the assessment here you see this right over here the lower soft. Here's the upper soft. The entire upper soft. It has had essentially no blood flow repeat that one over there on the profusion imaging. The lungs really lit up the chest wall the lower soft. We were really concerned about this one because on the outside it looked pretty reason we would have left it alone otherwise. But this is the beginning we're trying to understand this technology and see what was this really you know can really trust this. It looked very concerning that there was absolutely pretty much no submucosal blood flow that we could see. In this obviously a patient had a caustic injury so at risk for injury there's some of the blood supply right. And so we say well only close the chest come back in a couple days and reassess. That's what we did so a second look came back in two days and same thing I don't have the video of the black and white but you can see the green system injected again. And now the anastomosis starting to look a little more concerning it was starting to look a little more schematic a little more concerning and. And so we decided to take this an asthmosis down and give this patient a general or position that was a huge change in in practice that we wouldn't have otherwise done and I think we saved this patient a poor and automatic outcome and she's doing very well now. So that was a big eye opener for us in terms of how how drastic a change in course can happen with when you really understand the profusion of the tissue that you're working with. Plenty of other examples been an interest of time will move on now before we get into the recurrent winter of injury topic that I'm excited that we now have access to we got a software upgrade on our ICG spy fight system that we can quantify. With metrics the profusion I'll give you an example this quantification software that's it's real time. So if you haven't seen it you can set a baseline after the the the the the die goes in the ICG goes in you set a baseline away from the nest and most of the you can gradually move the camera and get a percent drop in profusion at the level nest and most of the we're going to try to understand what this exactly means and how much is too much of a drop. It'll at least to me allow us to quantify the width of the hyper profusion of the in estimate a little bit better and give some numbers to go along with our qualitative feature. So this is actually pretty cool. So I think in the next few months we've been doing a lot more of this and trying to associate those with our qualitative features that we've already looked at. So little sort of recap of what we're going to do next with the spy fight we're working already on our prospective validation cohort to reassess what we've already learned. And we've been incorporate these quantitative metrics into our assessment. We're also going to start looking at does this risk predicted center care improve the outcomes like are we are we doing better for the patients less days paralyzed less less poor and automatic outcomes by using this et cetera et cetera. So we've been see if this actually you know improves the outcome or not. I'm also going to want to in your future try to work on an animal model to try to work on some of these features offline to understand the tissue quality, the tension, the blood flow, what is this to try to get some objectivity to how to measure tissue quality and tension a little bit better than what we have so far. So we'll switch gears here a little bit because this is our other sort of dirty laundry in our practice that we need to improve on. But we have hopefully some time for questions at the end of my goal. But in essence, we're currently in an injury or the term is sort of a vocal fold movement impairment. I think it's an under recognized silent assassin for a lot of these kids. Unfortunately, it's not uncommon that a patient can get a great a soft, you an estimate that they can't use their soft, because they because they aspirate everything. So there's no point in that right. And some surgeons take the attitude of well, that's not my fault. The soft, it looks great. Let's have the the ear no some throat doctor take care of that and they stop on the patient and it's just they're not aware of these injuries, right. A lot of times because they don't look now it is appears to be that the left and nerve in a normal anatomy is most often injured from the right chest because it has a longer input for us of course. Now what is very clear and evident to us that we've been working more and more with the variant blood vessels. The location of these recurrent nerves can vary significantly if you're not expecting that based on an variant vestuature and you may be in for a surprise. Now there is some controversy between the use of a current, an injured or minor, most because in adults, you know, the data for thyroid is controversial as well. And so in babies, it's even more challenging because the we don't have the technology is as you will see here in the next few slides is difficult to apply to some very small kids. But I do think it's a preventable injury and we really try to we need we need to change our minds that to make this a never event. So I think that's what we're trying to do a little bit of data on this. This came out of Toronto and they have essentially a 50% injury rate with their H type T. And so this is really something that I think is unacceptable. And so I think we have to be better than this bottom line. Here also you see the prevalence of the lateral lateral where the left side was a lot more common in these types of these. And look at the proportion of bilateral injuries with the type E official as early age types. Now in our practice, we are we also heard a lot of nerves and this is sort of where we start with being honest of what we do. And so before we started using nerve monitoring, we did a retrospective review of this or of our EAT center database. Any at risk, cervical and arthrasal procedures included some of the cardiac cases that we've been doing in conjunction with the cardiac team. We took an approach to attempt pre-imposed operative flexibilities, a laryngoscopy on all patients. We think our L colleagues for putting up with us significantly increased their workload and burden of their workload for this. And the biggest thing was this, you know, the change in attitude because we used to only assess if they had symptoms and they had strider or not. That we started realizing that a lot of these kids have injuries and they don't have symptoms. And we'll show you those percentages. The thing I do was to check regards to symptoms and all of them because it's just such a high risk operation. Right. And so that is that that was a change in sort of practice. It was a little difficult because COVID came around and so for a few months, the assessments were done only on symptomatic patients or only if it's truly, truly critical. So the proportion of kids who got pre-imposed off assessments is not 100% but it still is very, very good. We'll look into that. So now before we start using their monitoring, our pre-existing nerve injury rate. And again, this is a very complex patient population. It's reoperative surgery was 21%. You can see here how some of these had came in with this is how they came into us. So about 10 of them are the 51 came in with bilateral courts. They were injured. Again, the majority were left sighted. So this is pre-op for us. So we've got pre-existing injuries on assessments out of these 241 51. Now again, this is a little messy because not all of them got pre-imposed off and the percentages changed a little bit. So I'm only got post-ops. I'm only got pre-op and some of you have pre-imposed off it. Not to get into the weeds here. Now this is this is one of the important ones. Like we're not we weren't a whole lot better than others. We've had a very challenging patient population. We still injured a lot of nerves. And so this is how the impetus for what we're doing and what I'm going to show you next. But about 21% new injuries. The very important thing here is that almost 40% were asymptomatic. So 39% had no symptoms of strider or difficulty breathing that was thought to be attributed to the vocal cord injury. So there is a significant proportion of kids who are asymptomatic who have an injury. Again, left side a little more common. We still had a few bilaterals. Some of these bilaterals were once they came in with one side of our injury and we heard the other one unfortunately. Now in terms of recovery or the natural history of them, about 40% of the new ones of the new injuries, about 41% did recover with time. We don't have the longest follow up and our hope is that more would recover with time. Interesting thing to see is a lot of the pre-up injuries that came to us already were already pre chronic or established injuries, only 16% recover with time. So those kids that come in with an injury to us, few of them recover. The lessons that we learned from this initial study is that it's a really under recognized issue. And it's a significant proportion of them. They're asymptomatic. We do think that all these patients should get a flexible nasal iron gas could be pre-imposed operacos in their symptoms and follow up as essential because some recover but not all. And this is where nerve monitoring we think has an important role to play. We, with the help of our oral colleagues, we took it on to try to be able to develop the technology to be able to monitor recurrence and their function and rapidly in any patient where others have their size. We've been very successful at doing so and they've been very tiny kids and we've published a couple papers on them. Now, we've all, a majority of us have probably seen the technology or the types of tubes and this is the one that is most commonly used in older kids. You only have sizes 5, 6, 7, or 8. So really it's not something we can use for kids less than 4. If you looked at our proportion of the age group of our patient population and significantly younger than that for the most part. So we like it when we can use one of these but it's not the most common scenario that we can use an integrated tube with the census already in place. So we first started off with the endolaryngeal brass electrodes. We did it again. Sorry. Must have not paid my PowerPoint subscription or something like that. Let me get back to that. There you go. I just got to switch the settings. Okay, so these are challenging. These are very difficult to place. If I could show I helped us a lot with placing this because they were challenging. They're placed directly into the vocalis muscle with laryngeoscopy. They can easily dislodge, especially in the long case when you're moving the breathing tube back and forth. They can also cost swelling in the vocal cords. I think we had a kid or two that they would try to extubate the next day and there was too much swelling. We think related to this. They're a little traumatic to the to the to the core. They work. They're definitely they work but they have their quirks. If you're doing a neck dissection, something that's a little more stable and it's probably easier to do is to just do a trans laryngeal press electrode. So the same electrode you can directly or precutaneously put them in the in the fire cartilage. And this actually works pretty good as well if you're doing a neck dissection. But it often involves having to do a deceptive plane. It's a little more stuff that the other ones would. Now we then moved on to these dragonfly surface heasts of electrodes on the end of tributum. And there's one that's a single channel and it's labeled for tubes that are as small as 2.0. And it works well but the problem is it's a little bulky. And also the you can only monitor one nerve at a time or you can only you don't know which nerve you're stimulating. And although by an atom you should sort of know what where you are. It's a limitation that's only a single channel. We didn't take that as an obstacle and we found this dual channel adhesive. This is rated for tubes that are bigger, you know, five or older. But if you trim it and attach it to the endotracheic tube and then figure out which of the leads that are active with a voltmeter. You can actually get a dual channel adhesive sensor on any type of tube. Actually this is our preferred approach now for kids that are younger than four years of age and actually worked pretty good. You have to sort of replace the lead that you cut in the neck with what we do to get a system. So this is what you see with the with the nymphs box in the monitor. You get essentially the electron myogram, a EMG of the callus muscle. And this is good to help you identify the nerve and to ensure that it's intact. But it often doesn't protect you from from a stretch injury or a which is I think I think more common scenarios. And so this is where we've been moving to using a lot of continuous vagal nerve monitoring with APS. So it stands for automatic periodic stimulation where you put the APS sensor around the vagal nerve. It's really cool how it gives you an audible beat of both the latency and amplitude of this graph of this nerve within has some thresholds of alarm that if you go if you stretch it, they go quickly tell you that you're doing something that it doesn't like and you can drop your amplitude or increase your latency. And you can see how you take away your retractor and it recovers the time. So the more you stretch it, the longer it takes to recover. So it really helps you to understand what are the things that we do that stretch it and one of the things that we can do to prevent that. So this has been very helpful to really learn and trust this technology and troubleshoot it. It's also a little bit of troubleshooting that once you start to understand things that we do it, it's a lot easier to protect them. Now we embarked on this project to look at what all these technology innovations, which are the equally effective equally successful in monitoring. This is sort of like our early learning curve of July to October of last year. Actually about a year of worth of the first year of nerve monitoring. We did about 122 address procedures 111 patients, small kids, as you can see. Tinyest kid had been around three kilos. This is an interquarter range. But I think we've done some kids that are two kilos and so forth. We were successful in monitoring the nerve meaning getting adequate signals in 96 cases. That was 84% success at monitoring. Occasionally, you know, especially at the beginning, the leads would fall off. And so we would be able to be successful with the monitoring. So we've been getting a little bit better with that. Now the majority of these procedures are in a reoperative field. Again, 23% was a pre-existing injury rate for this cohort. We've got a reasonable length of follow up for these kids. And we had in this early nerve monitoring experience, we had an injury rate of 16%. So getting a little bit better, but still not as good as we want to be. But this early experience was 16% between the age of 12 months for the injuries. So we still had some injuries. And this is sort of where we're getting at. We need to get a little bit better with that. So when we compare the different types of technology, the endolaryngial press probes, the dragonfly adhesives, the nims, the APS, they all seem to be equivalent for nerve protection. The nerve injury rates were all fairly similar in terms of fee values. The nim integrated tube, not surprisingly, was the most successful. There was no failures in that group because it's a lot more stable. A lot more stable system list things can go wrong. Between the press probes and the dragonfly adhesives, that was very similar. So you can see also how the age of the kids is different based on the technology, but that's expected. So the more important slide is this one. And this is sort of a spread off fresh hot off the press where we've been looking at. Our latest cohort after this cohort that I showed you since October of last year. So the next sort of year, a little less than a year, we've done another 106 cases. And our nerve injury rate has come down at 13.8. So we started off at around 21%. And this is sort of like all comers. These are like the checking everybody, symptomatic, asymptomatic. So that's probably why they seem a little higher than what has passed in reported. But this is really trying to look at every single patient. The more important one for me is that we've had, we've gone to from a 3.6% bilateral injury rate. The point eight to now zero on the late the last 106 patients we haven't had a single bilateral injury. So that I think that is huge. And I think this this technology has allowed us to particularly in the kids who come with a core that is already out. I think those are the ones that are at greatest risk for having another core out. And so if we approach those particular patients that already have one core that's out with utmost care and with their monitoring. I think we can prevent those from becoming bilateral injuries. So I still think we can get the low 10% of the article. So we'll keep working on that in conclusion. So we can have some some some time for questions and discussion. I do think that neuro-minoring is feasible in pediatric patients of all ages and sizes using commercially available technology. We are in talks with companies to hopefully at some point get integrated tubes that are smaller. We'll see that that comes to fruition. We've been chatting with the with the companies. The different types of technology that are available or devices are all similarly effective, although not surprisingly the NIMS integrated electrodes are a little bit better. But they all have similar rates on their protection. There's a significant learning curve to this, both in just installing, setting up, and troubleshooting the monitoring, the anesthetic management. We really thank our anesthetic team who have put up with us to do this very complex challenging cases and kids that are not paralyzed and beginning to look at us like we were crazy. That we've been able to in conjunction with them to talk about it through the case and get it set up so that it's the best thing for the child. And so we've been able to do very complex challenging cases with the kid not being paralyzed. So that's been amazing to it's also a different change of mentality in terms of just the neuro preservation strategy. A lot of these operations are really a neuro preservation dissection and trying to find the nerve protected. We've got a way to set up our retractors and exposures so we don't hurt the nerve after we find it. And so that has been a change in practice that has I think ultimately led to a decrease in the nerve injured rate. And I still think we can get better. At the end of the day, this is just one more tool, a couple more tools in our toolbox. And it's not going to be the only tool that we use for these kids. We have plenty of other tools as well, but I think the more we understand our tools and what we have at our disposal, I think we can help these kids better. We have to work harder because our patients are getting harder. We have to be better and we have to do this faster and stronger. And this is really a team effort. None of the things that I talked about today were done by a single individual. I definitely, Rusty, pushed us all with this innovation and relentless pursuit of excellence. And we are incredibly in awe of everything he did for this team. And we're very happy for his retirement and we're going to miss him greatly. But we're so happy that he left us with an amazing team of individuals. And I'm sure I forgot a few of those pictures and come up actually. Sorry. I'm sure I forgot a lot of faces in this graph. That doesn't mean I'm part of the team. I just couldn't find your picture online. There's so many people that are, you know, passionate and relentless pursuit of excellence for these kids. And I'm very thankful for everyone that has ever helped us take care of one of these child. It is very, they're very challenging and we have a lot of problems and complications of these kids that we help a lot of them. And so what we talked about today was just the snippet of some of the issues we're working on improving. And I think we can still get better. Well, thank you and I'm happy to answer questions and I'm looking forward to the discussion. Well, Ben, I could take the privilege of jumping in and saying, wow, what a tremendous talk. And you emphasized, you know, at the beginning throughout the end, why this is possible? This is not the takeaway from you, but this is a team effort. You can tell by looking at who's on the screen. We have lots of people from outside of the prostitutory at the time of the morning joining our grand rounds. Multiple GI or a pulmonary colleagues, people from the OR, others. This is not done by one person. The fact that you could present inter-radar variability with four people from one specialty evaluating the videos is the statement of a team having been built. And these kids can only be treated in this way to this degree of comprehensive analysis and care at the moment, the Boston Children's. Imagine, like, I was looking at some of the data you were presenting. You analyzed just in this 55, 77 the soft-gill and asthmoses in 17 months and almost all 17 of those months were during a global pandemic. Just think about that. Imagine going to, let's say, for the fellows, going to another institution. And imagine doing 77 soft-gill and asthmoses in a decade, I would say would be an enormous volume. It's just incredible. What you're showing is the evolution of innovation. Innovation is not a one-time, aha moment. You start with a grand thought. What you demonstrate is, over time, if one keeps their eyes open, it moves to a nuanced phase of innovation. Now you're looking at arborization on splyfoc. It didn't start that way, right? It started with a patient who decided with the long gap, deciding to go to Minnesota. And Rusty Jennings saying, OK, I'm going to ask Jack Foker if I can come to watch. And Rusty realizing there's a better way to do this than what we're doing. And some of those are all enough to remember what we're doing. And we, he and Bob Shammerger, brought Jack Foker here and said, help us show us how to do this. And we, at a big institution like Garz, got a large volume quickly with his help with Rusty's leadership. And a lot of other people, lots of blood-switten tears. Mike Mennfreddy jumping into a field that didn't exist. And inventing techniques that were required with he and Rusty brainstorming in early days. What didn't happen here was beating the chest and saying, we're the best we've done at We've solved the problem. Some of us, many of us, we remember the days where we were using John Foker's technique of pulling because tissue should grow. And then finding out, actually, you can't pull anything. And the stars don't always stretch. And the team saying, let's find another way. And then evaluating the techniques. And now we do routinely scheduled reserved scheduled on the stop for regional interpositions. And bringing in another portion of team with microsurge. That's become a routine operation, which you've all published on incredible success. But didn't put your head in the sand about what the complications were. You just showed us an entire presentation, basically, of revealing, as you say, the dirty laundry and how to address them, how to solve it. Going out this firefight, going out to nerve monitoring, publishing the numbers. This is how many nerves we damaged. How many times you see surgeons, procedures, can't even say we, and publishing it. We've hurt children, right? As we're helping them. This is an extraordinary experience. At the moment, this can only be learned here. It's interesting now that this has grown to such a huge experience. Our trainees get just an unbelievable experience. And now, Hester, we will take this to join Jason and the two of them. We'll really be able to have not as big a team as we have here, but it has to happen not just in Boston. But this shouldn't happen in every children's hospital in the country in the world. Because the reason that we have this number of patients, most of which are reduced, they have complications elsewhere. This goes too many people were trying to do something that used to be easy, and then they ended up nothing very good at it because we don't each do it individually and often. I do want to take the opportunity to comment on that. For two, it is timing of this grand rouse. I did not know that this is going to not just plan a year ago. We didn't know a year ago that Rusty was going to retire. So it is quite fortuitous that this happens just after Rusty's had a little time to catch up on his sleep and to catch a few deep breaths. And I'm so thrilled that he joined us this morning. Rusty rebuffed my multiple efforts to try to publicly celebrate his career and to have a party. He's an out party kind of guy and we are finding ways to thank him and to honor him and to have permanent demonstration of his incredible contributions to this department, to this institution, to these children, and to the field, a field which he really can't. He really can claim to have created. As he was walking out the door last day, he was expressing his frustration to me about the things he wanted to get done and didn't get done, but did us other things that are important to this life. And I said to him, I hope that after a little time to take a breath and to look at things in perspective that you'll be looked not at what you didn't get done. But what that you did achieve in medicine, particularly American medicine, is not a place in the institutionalization of what we do things which easy to advance. And what has been accomplished here is I think I hope Rusty can see that this is your legacy. What Ben just showed, not just him as an individual, but this whole team field is your legacy. And so I'm sorry to take up the podium, so to speak here, but I wanted to take the moment, sorry, but to honor Rusty, since he wouldn't really let me do it anyway. And he's captive here. And so I want to say what an incredible passage of the path on this is from Rusty to all of the rest of the many people in the Eats Center and beyond. And I'm looking forward to the continued transparent presentation of the outcomes and the innovations. I will leave it to others to ask questions. I do have questions. I've asked Rusty about like, can you put a tensiometer on the anastomosis and then it seems that those kind of more sophisticated quantifications are coming. But then great job to the whole team. We are so proud. And to Rusty, you need to be proud and you need to let us thank you. Thank you, Steve. Thank you, Steve. I'm incredibly proud. I'm so impressed. And Ben deserves just a tremendous amount of credit for going through just dreams of data that was collected, sort of in a half-hazard fashion and making order of it. And the approach to complex surgery needs to be transparent and totally honest in order to make these advances. And I have to say I think Ben's done a young man's job, really fabulous job. And I could not be more pleased to pass the time. I'm always here if I can provide a good question or good answer. It's obvious just by this picture that it's amazing team. And what you may not see in this picture is that most of these people are friends. They like to hang out together. And I think that's one of the keys to a great team work is having people who work well together, can freely open up their ideas and freely exchange opinions and move forward. Congratulations to the entire team. You are the world best and I could not be more proud. The challenges, including the pressure not to drill for ourselves. Any questions? I'll get five minutes. I'm sure there are questions. So Ben, I have a slightly sideways question. So the bit of controversy about neck dissection, particularly in thyroid and parasites and recurrent nerve monitoring, that it's not worth it because you want to protect 1% of the nerves. So taking that information and translating into thoracic surgery or mediastinal surgery has been, as you know, with psukitroid and uid, conjacent is extremely difficult. But I think it's going to be the same ramp up. And I will say that we had progress and significant advances with cardiac surgery, particularly with Chris Baird, but some of the other guys is neural and cardiac anesthesia for a nerve monitoring. So I would encourage you that's a little seed that's been planted. And there's an oak tree behind it. You just got to give it time to grow. It's a really support, mediastinal surgery and recurrent nerve monitoring because I think it's a huge deal. But with the data we're collecting, we can easily come up with a number needed to treat. And just based on the prevalence of these injuries, a lot more of an argument that these cases should be done with their monitoring. No question in my mind, particularly any reoperative case, I think should be with them in their monitoring. And I must say, I don't know why any of the unreoperative shouldn't be done with their monitoring. I think in the first place it's, although you can see the nerve a lot better without scar tissue, you can still stretch them. And we certainly heard a few of those by stretching them by looking at the nerve dissecting it perfectly at a retraction system or the way we pulled on these affigates, the stretch that I think that's where we need to improve. I will say that cardiac surgery faces a daunting problem because they are under time pressure incredibly complicated to sections. And these kids are sick with abnormal lymphatics and sometimes recurrent infections, reoperative fields and nerves and lymphatics can look so similar. They're a very, just as big a challenge as we do in a softened, dual mediastinal reconstruction, but they're under time pressure. They have to move. Yeah, they're also a lot more used to energy that fiction because they're they're bypassed and they don't like bleeding. And so they use a lot more pottery close to the nerves than we would ever do. So it's your right is something that. I have to work much to learn from each other. Well, this is the questions or comments. Ben, it's Peter. Yeah. Question for saying excellent job, excellent presentation for their recurrent laryngeal nerve monitoring. I know that it's not necessarily so easy and it sounds like it's it's potentially useful with the thoracic surgeries. But do you have either from experience or data, anything to point to the operator learning curve? That's what we're trying to get at. I mean, I think we have the numbers to look at that. I think we have all it's going to be hard to look at that as an individual surgeon because we've sort of take tackled this these cases of team. So I'm probably going to be our team's learning curve because it's not just the setup of the sticker on the breathing tube. It's like how the anesthetic, the management, the interrupt trouble shooting. And so yeah, we'll get to that. I mean, I think we we have seen that are I didn't show that today, but that J J am I working on that now, in terms of we're looking at our success rate in terms of just like the ability to complete the case with satisfactory nerve signals is this is getting a lot better. We're having a lot less technology failures, if you will, that learned to set it up better. Now we just got to get better at protecting the nerve. And a lot of that is probably just more proactive use of the APS monitoring system. I don't know that we have the data yet to say that the APS has been the main factor of it. Definitely, I think is a lot more proactive at telling you when you're when you're doing something that the nerve doesn't like. So we'll get there. Well, with one that left, I think we need to again, thank you. And this is something as an institution. I think we can applaud with incredible pride that the progress that's been made here. The things that you're talking about, like putting, you know, routinely monitors around the biggest nerve, propanatively, the measure. I mean, these are things that took forever and a day. It seems like the get to, but if you look at it in big perspective, we went from calling on SCAR to various investigating management to, you know, something's just seemed like they're just too challenging. I look back at the days when we started doing robotic surgery and we take like all day to set up the robot and get figured to it. You guys are getting efficient, really efficient at doing this so that putting the current nerve monitors or vagal nerve monitors on is kind of like routine thing, like putting an a-line in just something really to champion. So thank you for all of the non-general survey people on this screen. It really is due to all of you that this team has been so successful and we're so pleased to have such incredible notice of like, aberration is way too many of you to thank all of you who are here on the screen and those that couldn't attend. Thank you. On the way to with a great day. Thanks, everyone. Thank you.