Lung Lesions: Fetal Interventions Parts I+II

Um, I, I guess the, the one thing that I was surprised by is the number of cases that, uh, they've done an exit procedure with, uh, with a lobectomy at the time of exit procedure because we've. Not had a case where we thought that was necessary. Well, uh, everyone realizes you don't have much volume in Toronto, Jack, so I'm not sure that's legitimate, but, uh, you know, certainly, uh, you could argue that we have overused the exit with, uh, CAMs. There's no question that some of them definitely required it and benefited from it. You can also, uh, say that in some cases you can squeak kids through with some risk of mishap, uh, by not doing an exit procedure, um. As I said, I think we've gotten more selective as time has gone by, and we really reserve it for, you know, the average CVR on them has been over 2, which is those are big lesions, and we reserve it particularly for cases where there's evidence of compression. So you have diaphragmatic aversion, marked mediastinal shift, often ascites and other issues. Sometimes the kids are a little premature. So for a variety of reasons, you want a nice controlled. You know, resection without the need for any kind of emergent ventilation and potential for hypoxemia. So, um, you can argue that we overuse it. I, I think for the most part it's been, we do get very severe cases of CHP, and I think it's been justified. OK. When do you do the ECMO? Was that during the exit procedure or are those for patients, uh. No, Required ECMO during. We haven't used exit to ECMO. We always give them a test of, uh, conventional ventilation because it's very rare to need ECM in, uh, CCA patients. Um, very rare. JM. Jake, I was going to say you have to remember they're in the states and everything is bigger, including the sea cans. That's right. I can imagine what it's like in Texas. That's right. I think what Alan says is true when you look at the number of patients that required ECMO. I mean, I think they're getting referred complex cases from all over and all the simple cases are staying where they are. So their view, their percentage of exit and percentage of fetal surgery, I think is skewed. It does not represent the true natural history of these congenital lung lesions. Alan, we have a question from, uh, did, did you want to respond to, to Jean-Martin? No, I, I agree with him, OK. Um, we have a question from, uh, Ravindra Ramadwar. Uh, he says, what is the incidence of subsequent conception after fetal surgery? That's been studied about, uh, 4 times now and, and published, and, uh, basically, uh, there's no clear reduction in the ability to have subsequent pregnancy after fetal surgery. The difference is you're not allowed to labor after you have the incision that's performed with fetal surgery. So, it's equivalent to a classical cesarean section in the upper part of the uterus. And those patients should never, uh, labor with future pregnancies. But we've had very little in the way of any long term, uh, maternal morbidity aside from the requirement for cesarean delivery. And, uh, overall, we've had, uh, none of the really feared complications like uh placenta accreta uh at the hysterotomy site. Uh, those kinds of things that you might anticipate occurring haven't been uh observed thus far, fortunately. Any questions from you, Steve, at all, or John, John, do you mean well, I, my question was about the exit procedure. You know, at Akron Children's we're certainly nowhere near the level you are at CHOP, and we've never done an exit procedure. What would be your thoughts on, uh, a, a pediatric hospital that's busy? Starting up a, a program like the exit procedure, what, what, do you have any, any discussion. Well, I mean, the exit procedure, uh, is different. And it, it's not a cesarean section. It requires an anesthetic team that's very tuned into the issues required for uterine relaxation and the maternal issues. It requires, uh, uh, expertise with the hysterotomy and, uh, so, it's a whole team of people that do it. It's certainly something that I think, uh, uh, a, Qualified team can learn and be trained in, uh, come observe a few or whatever, um, uh, without having to have a fetal surgery program. So, I think it's something that's, uh, can be more widely disseminated than fetal surgery can. Uh, but it's a very valuable, uh, part of, you know, what we do as pediatric surgeons. We do a lot of cervical teratomas, uh, airway, uh, obstructive problems. So, we've done, uh, close to 100 exits now at CHOP in the past 10 years or so, and that's, um, you know, again, we have an unusual referral volume, but I think, uh, most hospitals experience kids from time to time that would benefit from an exit. Most large children's hospitals. So, I think the key is, I mean, we perform exit procedures, but the key is that you have to have the maternal expertise. Um-hum. At your hospital. And so, I think to bring a, a mother into a freestanding children's hospital that doesn't have the maternal expertise is probably a bad idea because you have to, you have to protect, first and foremost, you have to protect the mother. And so. Yeah, that's absolutely right. So, I, I think in most places you would need a children's hospital in association with a maternal center. A few places have them together, um, but if you have the, you know, if you have all of the components to do an exit, there's no reason why you can't. Learn to do an exit procedure. How many places in the US or around the world perform exit procedures? Is it? I really, I don't know the answer to that because some people. Call it a glorified cesarean and exit procedure. Um, I don't know how many do it right. There are probably 4 or 5 in the US that OK. You know, clearly have the qualifications and, uh, the background to do, Good exit procedures. You know, uh, the limitation is, is having a freestanding children's hospital, uh, is, you know, without the maternal fetal delivery. Well, even if you have, if you have, you know, for many years a job before we, we developed an in-house fetal center, uh, we went over to University of Pennsylvania or we brought the mothers back and forth, uh, to do the fetal surgery, so. Uh, if you have a, an adjacent connected, uh, obstetric center, then, uh, it can be done. Yeah. But it's, it, I mean, it, you shouldn't underestimate, it's, I mean, Alan's so good at it that in their centers so good, but I mean, it's a, we did one a few weeks ago and it's a huge undertaking. I mean there is weeks and weeks of planning to go in. Discussions of the entire team. There's, you know, in our center, there's 15 to 20 people who are involved. It's a, you know, there's all sorts of things that go on. And so, I think it's not something to undertake. Yeah. Lightly, but it, it can be done very well and very safely. And I, I think if you do one a year, it's probably not enough to justify doing exit procedures. If you have the potential to do 3 to 5 a year or something, then it's probably something that is, uh, a reasonable thing to think about. Um, Alan, we have a question, uh, from Sweden. Uh, Doctor, uh, Naji says he wants to know your opinion about conservative management if the fetus or newborn is asymptomatic. Well, we're gonna, we're going to get to that, uh, in my next talk, which is on postnatal management. I'm sure there'll be a lot more discussion about that than, uh, just about any other topic. So, um, why don't we reserve that, that answer for the next, uh, presentation. Perfect. Alan, I have a question. Yeah, OK. Um, we see, uh, kids occasionally with, uh, either a, a sequestration or a hybrid lesion that has a large feeding vessel, and those kids will sometimes develop pre-hydrops or high drops. What's you're thinking about, uh, the approach to those? Is there any, uh, role for trying to ablate that vessel as part of? Well, I, I think you have to ask what the mechanism of the hydros is, uh, Jack. I've seen very few, if any, where I thought it was a high output failure form of hydrops. It's very rare. Most of those BPSs that cause high drops usually have associated pleural effusions, mediastinal shift, and high drops on that basis, or their mass effect is enough to result in high drops. So I think, you know, if you did have one, which again I haven't seen. That was a high output physiology, uh, based on their systemic feeding vessel and, and shunt, um, then it might make sense to, uh, I think, do a fetal operation to, uh, correct it. I think some people have advocated doing, uh, embolization or sclerotherapy procedures. And, uh, I guess if you don't have the capability to do fetal intervention, fetal surgery. You might consider that, but it really is something that, you know, injecting alcohol, for instance, into fetal vessels or even embolic substances into fetal vessels is something that I think has quite a bit of potential hazard. And hasn't really been adequately studied, you know, things like neurologic effects of using alcohol as a sclerosin in the fetus, I think, are, are very worrisome. And so, I personally, I'm not a big advocate of the lesser, less invasive approaches. Um, I don't think they're indicated very frequently to begin with, and I think if you have one of those lesions, it would probably be better served by. If you're capable and open approach or referral to a center that does open surgery. Your, your video that stopped short, um, there's some questions about that. Uh, talk to us about how it is different doing a lobectomy in a fetus of 23 weeks. Is it, is it the same as, uh, what are some of the technical challenges, some of the differences and findings? Well, I think, um, the basic operations the same. What's different, different is the consistency of the tissues and the size. And the size, I don't think is a major limitation. As, as pediatric surgeons, we operate on neonates, premature infants. 28 weekers, etc. And so, the, the size difference isn't uh really the limitation. What the limitation is, is the delicacy of the tissues. And as you get down to 23 weeks, if you get down to 20 weeks like we currently do with myeloma. Meningocele, it actually begins to get very gelatinous and friable. And so, um, you really have to be very careful. And the mishaps we've had have usually been related to traction, to things like that where you tear tissues that, uh, you wouldn't normally tear with open surgery. We use, uh, most of the same instruments, although we use things like Q-tips and stuff like that that are a little more delicate for some of the fetal stuff. But, um, overall, it's not, uh, I don't think that much different than doing an operation on a premature infant until you get down to the, the point where the tissues are, are really becoming, uh, gelatinous and have poor integrity. OK, so just like a minor point. So, we spent all this time positioning the babies for our open surgery or thoracoscopic surgery. How do you position, Is it moving around? How do you stabilize the fetus? Well, the, the fetus is anesthetized. So, you have anesthesia from the mother. Yeah. And you have a, an anesthetic and paralytic shot that you give the fetus in addition, so the fetus isn't moving around. OK. You position the fetus before you open the uterus. So, you've got an amniotic fluid space and you convert the fetus to the position that you want to, Him to be in or her to be in. And so, if you're operating on the chest, you really want to get the arm on that side out of the hysterotomy to expose the chest adequately for a thoracotomy, right? And then you stabilize him with the arm and they're sort of like a quirk in the fluid with the hysterotomy, right? So, you're infusing amniotic fluid. The fetus will come up and almost seal the hysterotomy. Um, and it'll be buoyed by the, uh, amniotic infusion underneath it. So. That's so cool. It's fairly stable. It's not, uh, you know, the penis doesn't move around. It doesn't really. Cause you do put. While you're out. You don't put like, uh, something on either side of them to keep it. Nope. Wow, OK. It stays fairly stable. Once you control the arm for a thoracotomy, it's. Right. You pretty much have them. OK. You have them where you want them. But have you had to do any, uh, Doctor Flake, any pneumonectomies on, The fetuses and what are the, what are the long term issues with that? Yeah, we've, we've never, um, done a complete pneumonectomy successfully. We did have a case, I'll talk about a little, uh, later, uh, bronchial, uh, main stem bronchial atresia. That uh. We tried to do a pneumonectomy on and that, uh, infant didn't survive the fetal procedure. So, we have not had a successful pneumonectomy, um, thus far. But we've done bilobar, bilobectomies. We've done, uh, Resections where you leave a very small piece of, because a lot of these kids will have abnormal fissure formation, and so it's very hard to sometimes, uh, separate them in an anatomic fashion. And we've had a number of kids where we've left and, and the residual lung tissue has been compressed and is very small to begin with. So, we've had a number of kids where we've left a very small fragment of lung in one, pleural space and that grows dramatically. Um. It's amazing how, how much a small piece of lung tissue will grow as long as you preserve its, You know, airway and vasculature. Ramesh wants to know about, um, if a mother has had earlier C-sections, can you still do fetal surgery? Yeah, we, we still can. Uh, the uterus heals, uh, incisions fairly well. Most C-sections are done through the lower uterine segment. And so if that's the case, it's really not an issue for interference with our incision. Um, if they've had a classical cesarean section, which is fairly unusual, then we would simply make sure ours is somewhere else. Jack, you, you had mentioned that you don't, you guys haven't done fetal lobectomies, right? So, Oh, we're not hearing you. Not hearing me now I can hear you. Yes, uh, what fetal intervention have you done for thoracic? Uh, any, have you done, are you doing, uh, any thoracic intervention, not just for lung lesions, but are you doing tracheal plugs or, or anything like that, or exit, or what are you doing there? Uh, we do excess mostly for, um, uh, for neck masses, um, and we, uh, done quite a few shunts for macrocystic pecans, uh, with pretty good success and, you know, similar kind of numbers, uh. Test numbers, not certainly gross numbers as the, uh, done. Um, we've also had a couple of kids, um, like I mentioned before that have, uh, uh, bronchopulmonary sequestrations or, uh, hybrid lesions with a large feeding vessel where we've tried to occlude the vessel, uh, using a number of different techniques, uh, in the thinking that. Doing that might shrink the lesions, and we did one where we did a shunt and we occluded the vessel. So, uh, had mixed success with, with those cases. We've only done a handful of them. How have you tried, have you tried to occlude the vessel, Jack? What, what technology have you used to occlude the vessel? Tried radio frequency ablation, which was a disaster, so I wouldn't recommend that predictably. Uh, the last one we used coils, uh, which were actually good initially, but then, uh, the fetus died about a week later for reasons that weren't clear to us. Um, and then we've also, uh, I guess we've used injection of, uh, alcohol as well earlier on. And my, my worry with alcohol injection, uh, which has actually been documented in a case that, uh, I was made aware of, is that it can go, and this was for a teratoma, um, but it can go through the shunt, right? So, it's not necessarily going to stop where you inject it. It can go through the vasculature and actually cause thrombosis in the systemic circular in the, uh, in this case, it, it, it was first noticed in the chambers of the heart. So thrombi circulating in the heart and then they go out to various sites and so that's one risk and the other, I think, is just, uh, you know, if, if it does go systemic and nobody's even studied this experimentally, which is amazing to me, you know, that you go and you inject alcohol in a fetus. And you haven't even studied in a sheep, you know what happens when you inject alcohol in circulation, um. You know what effect does that have on neural development and other other organ development in the fetus? It's just very worrisome to me. I, I don't think it's a good thing to do. I haven't done and the radio frequency ablation thing is very attractive, but because of the fluid content in the fetus, you simply can't control the heat. You know, the fetus is 90% water and. Uh, I put a radiofrequency ablation probe in one side of a teratoma after we resected it from a fetus and turned it on and watched, and suddenly the other side of the teratoma began to boil, and that's where the energy dispersed. And so it can go in any direction and cause collateral damage. And we have studied that in labs, and it can, it, it causes a lot of collateral damage in the thorax and other places, so. We, and as I said, that was a disaster and we would never do that again. Yeah I think just, it's important to keep things in perspective. I mean, probably 95% of the C cams I see now are prenatally diagnosed. And in, In the, you know, we're, we're talking about the end of the nth, um, the experience of CHOP or that you might have up in Toronto, but almost none of these lesions require prenatal prenatal intervention, and in fact very few require. Intervention the day the child is born. And so it's just, I mean, so just for the audience out there to understand that the vast majority of these lesions do not fall in the realm of these, uh, what, what are very exciting and extreme treatments, but there probably are only one or two centers in the world that should even be thinking about these kind of interventions. Cause the, the end is so small that, that, um, you don't, you don't want to think just because someone has a cyst on their, On a, on a prenatal, uh, sono or MRI that you need to put in a shunt or if there's a feeding vessel that you need to think about doing something about it. Cause the majority of these children can be delivered and, and don't even have fetal distress at that point, so. Uh, and that's been our experience here. We, uh, have had a few that we've referred to Cincinnati to Tim Crummer Holy, uh, because of, uh, the progression or the development of eye drops. Um, I've had patients where the eye drops went away and the patient didn't even, I couldn't even find the CTM after birth despite a CT. You know, a year later. Uh, so, that child was seen for fetal surgery. Fortunately, it regressed and nothing was done. Uh, so, we, we've had that experience as well. Yeah, and I, I completely agree that the majority of these lesions don't need fetal intervention. They do need fetal evaluation. Right. And, uh, I can't tell you how many lesions have been, uh, have come to us after a, uh, recommendation for termination. By people who don't really understand the natural history of these lesions, uh, even when they're very large, they can regress and be asymptomatic at birth, or they can have very good survival rates with the kinds of interventions that we do. So, I think it's important to understand the prenatal natural history, uh, that people do understand that, you know, the garden variety postnatal cecam is very different than some prenatal secams that we see. And that there, there are places that you can refer these patients where there are options other than termination or fetal loss. What you describe as a disappearing secam, I think, is an incredibly unusual, if ever present lesion. And, uh, there are some things that look like scams in utero, like, uh, uh, segmental bronchial stenosis, things like that. They give you an echogenic microcystic appearance of the lung. But true cystic scams, uh, you know, we get, we see them all prenatally. We get CT scans on them all postnatally. They often regress. They often become very isoechogenic at the third trimester where you can't see them anymore. You can get a chest x-ray at birth and you don't see anything. But I can't think of a cystic ceca in utero that I got a CT scan, CT scan on, uh, a month after birth that wasn't still present and still prominent. So, I, I don't think true cystic secams disappear. They regress, but I don't think they disappear. And there are some things that can look like CA that we've got a better understanding of more recently that are usually in the bronchial stenosis atresia sequence that I think can be very minimally apparent or non-apparent after birth. We have about 4 minutes left and I want to, we have a slew of questions, so I want to see if we can do sort of rapid fire answering here. And then also Jean Martin. If you have any comments, uh, about, because I know you're doing a lot of this up at your center and wanna hear your, your input or comments or questions about what we've been discussing, just, uh, speak up. Yes, I wanted to speak up and actually talking about speaking up, if Jack can put up his level of the sound that we would hear him better. One question I agree with what Alan was just saying, but in that respect, I don't think we should call the CCA. We should say congenital lung lesions, and they're either macrocystic or they're hypeechoic or mixed. And this would avoid the confusion saying sea cams disappear because I agree with you, Alan. Sea cams don't disappear if they are really sea cams, but secam is a pathological diagnosis once a specimen is in the bucket. So that's one point I wanted to make. The other one was about the exit procedure. I think there's many tertiary centers who have the capacity to do an exit. I think it requires a huge team approach and somebody leading the team, but many people could do it. What's more important, I think, is the indication for exit because people start doing exits and then they want to do exit for all sorts of things. I'm aware of a case that prenatal. It looked like a huge hypeechoic lung lesion, mediastinal shift, very severe. They couldn't get an MRI done. The mom was too obese to fit in the machine, so they decided to do an exit, and I'm not sure why, because they just did an exit to intubate the baby. The baby did fine, ventilated well, actually extubated himself two days later, was fine, and it turned out to be that this baby had a congenitally absent. Lungs. So what looked like a CA with a medicinal shift was actually the only lung that there was. So thank God that they didn't do an exit to lobectomy procedure, then there would be no lung left. So I think you really have to be careful with the indications. Well, I think, I think what you're pointing out, Jean Martin, is that you really need good prenatal diagnosis. OK? Yes, and prenatal diagnosis is not equivalent in all centers or by all practitioners. And we very frequently, as I mentioned in my talk, get lung agenesis that have been diagnosed as microcystic secas elsewhere. So it really is an art, and you need people that are very good if you're going to practice this kind of medicine and not refer to a fetal center, you need to have great confidence in your prenatal diagnosis or you make terrible mistakes just like you mentioned. Absolutely, and remember to first do no harm. So if you're not sure, better not to put the mom through an exit because it is more invasive than a regular C-section. Hey, uh, Jean Martin, quick little plug, can you tell us about the conference you're having up there, uh. Pretty soon, right? Esophageal atresia conference, yeah, uh, October 8th and 9 in Montreal. OK, so Jack is coming and Steve and I hope that many of you can come as well. Many good invited speakers. So it's going to be focusing on esophageal atresia, uh, both the surgical tricks, but also the long term follow up. Perfect. Thank you. Yeah. Um, yeah, actually, yeah, Jean-Martin, if you can get us, uh, type a little text at the thing about a link on how people can learn more about it, uh, if there's a, a way they can learn more, that'd be great. Um, I'll do that, we have a, uh, Phil Hammond, your question we're gonna talk about in the next session which we're getting to momentarily about which CCMs you res you resect, um, or actually, I'm sorry, lung lesions you resect, um. Michele Torre uh says, can you clarify to me the role of the pleural amniotic shunt? Yes, uh, uh, we, we use it very, uh, specifically for macrocystic se cams, uh, that have, uh, evidence of high drops. And so by high drops we mean fluid in, uh, or skin edema. Um, it has to be more than just ascites. So, pure ascites is not necessarily hydrops. It can be simply related to the mediastinal shift and, uh, hepatic pulmonary or hepatic venous return. Uh, so we require a pleural effusion, a pericardial effusion, and skin or scalp edema. And that's when we use, uh, Uh, pleuro amniotic shunts. We avoid putting them in prophylactically. Unless we will tap large macrocystic lesions just prior to delivery sometimes to improve ventilation, but we don't generally put in a shunt unless the lesion is causing evidence of high drops. Uh, OK. And then Kurt Koon says, uh, a question. Basically, when should we refer to a fetal center? When you're not comfortable managing the patient, OK? So, I, I think, and, and, you know, obviously it, it depends on the, the wishes of the patient, but they should certainly be offered the option of referral to a fetal center if, uh, they've got a, a very large lesion, if they're requiring very frequent, uh, monitoring, if you don't have adequate, uh, uh, Uh, radiologic or maternal fetal medical support to do good prenatal diagnosis and to follow these lesions closely. Um, and if you don't have the ability to intervene if it, uh, develops eye drops. So, I think, you know, those are, are the reasons I would refer a patient. If you can't fix it and you're worried about it, then, uh, that would be the time to send it to a fetal center. All right. Uh, I think that's actually a pretty common question and I'm glad someone asked it. Uh, what CVR would be considered safe antenatally before intervening? Would be considered safe antenatally before intervening. Well, I mentioned that the CVR is just a, a estimator of size. And so, the physiology is really what you're looking at. And the CVR is valuable for prediction of, uh, adverse physiology. So, uh, we use a cutoff of 1.6. As I mentioned, it's very, very predictive with microcystic lesions. So, if you have a less than 1.6 on presentation of the CCAM, Um, Then the likelihood it'll evolve hydrops is about 3%, 3 or less than 5%, and that's a pretty good predictive capacity, and that's held true, uh, both in the prospective study that, uh, Tim Crummelholm published when he was a CHP, uh, on through our ongoing experience. So it's very unusual to have. A CVR of less than 1.6 and a microcystic lesion, uh, evolve into high drops. The corollary is also true. Greater than 1.6, uh, they need to be watched very closely, and there's a much higher likelihood that they will evolve into high drops. And macrocystic lesions are a little bit of a wild card because the cystic component can, uh, grow very rapidly. And so, uh, they can be, uh, worrisome even if they're, uh, less than 1.6. Uh, when would you plan a fetal MRI? We get fetal MRI's routinely for, uh, but, you know, that's what we do. So, um, so, all of our, uh, lung lesions get an MRI prenatally. And, you know, I think MRIs are often helpful in defining the anatomy, um, and, uh, You know, just the, the general size of lesions for me because I can read them easier than ultrasound. Um, but I don't think, uh, they're essential, you know, for all centers to use. So, I think MRIs, uh, can clarify, uh, abnormalities if there's ambiguity on the ultrasound, if there's confusion about the diagnosis. Um, you know, those are the reasons that if you don't routinely get MRIs, then I would get one. Yeah, I would just, uh, I mean, in a center that's not quite as geared towards the fetal aspect of it, we, you know, unusual cases, we'll get fetal MRIs, but most of the time we just follow these patients with the fetal ultrasound and then evaluate the patient once they're, they're born. Um, honestly, part of it's just a, I would love to have fetal MRIs on it. It's just a practical and cost issue that it's, it doesn't change the management in the prenatal portion. Um, very often, um, except for in these extreme cases, so. Well, you know, MRI is better for some things and not as good for other things. And so, it depends on the fetal anomaly you're talking about. If you're a fetal referral center and people send you patients, uh, that are, uh, difficult for one reason or another, I think you want to get all the information that you can. And an MRI often, uh, you know, contributes in one way or another to our understanding of the lesion, so. Uh, is there a registry like we have for ECMO for fetal surgery and, uh, or for, uh, the exit procedure? No. Get on it, yeah, so, uh.