For the one spectator we have here, this is Jorge Larco. Jorge, he's a radiology resident at Henry Ford, and here to talk about thrombectomy. So let's start. So good morning, everyone. Well, as our moderator said, I mainly built ex vivo, in vivo, and 3D models for testing intravascular devices and catheter development, including the computers that go with it for what is going to be a clinical purpose. So today I would like to present an ex vivo human heart and lung thrombectomy model, specifically for pulmonary embolism. I don't have any disclosure to mention for this work. So preclinical testing platforms for endovascular technology have been rapidly evolving on the last decade. And by using now 3D silicon and animal models, test beds are available to control the quality and improve the performance of endovascular devices. Although the reproduction of the human anatomy is extremely complicated, and not only the geometrical anatomy, but also the physiological conditions that we would like to have in a human being during, in this case, a pulmonary embolism. Partial evaluation of failure modes and mechanisms are implicated on the development of endovascular technology. In this case, it would be the application of failure mode and effect analysis for each one of the devices that will go clinically into practice and use. So the goal of the study is to create a reproductible and standardized model for catheter-based pulmonary embolism, treatment using ex vivo human heart and lungs specimen, and radiobased clot analogs to create the whole picture of the pulmonary embolism. So in here, two key words, reproductible. Once we have tested in our centers, you can have it in all the centers just by following the same secret sauce or same protocol of development. And standardized, you will know exactly what happened with the model without doing everything that has been used to test it on the first place. So the cadaveric model, we used two fresh, never frozen, lightly embalmed, and in 4% formalin, human heart and lungs. Our previous work in the neuro field allowed us to test the 4% formula of formalin and do mechanical testing of the arteries. So we don't have a bias here about how hard or stiff the arteries will be. Normally, when you mix the formalin, the arteries become mechanically unstable and rigid. In this case, we have proven in other works that the 4% formalin allows a good preservation of the cadaveric samples in a refrigerated temperature for a long period of time, between six months and one year. In this case, the setup for the catheter insertion will be an inferior vena cava 26 French sheet to be cannulated, superior vena cava cannulation and tubing connected to a pressure pump system to deliver physiologically accurate flow to pulmonary arteries. And also, it would be important to connect the trachea to see the flow movement of air in the lungs. That would be a problem when you're doing fluoroscopy, as this movement will alter if you're going to do a roadmap baseline angiography. So this would be the fluoroscopy and angioscopic vascular evaluation. So here, we have a peristaltic pump connected to a saline reservoir. We're going to infuse blood-mimicking fluid inside of the superior vena cava and infuse all these blood-mimicking fluid into the pulmonary artery. We have a standardized medical ventilation just to keep the movement. And in this case, that would be the important part, not physiologically accurate. We're going to use a standard angiography unit in this case to have these kind of images. And this would be just the standard DSA image and the connection, just not to lose this fluid and connect a pressurized system. You can see the movement here of the lungs. So this will be the analysis and the fluoroscopic view. You see the quality distally of the arteries. After death, the post-mortem clots form extremely quickly. And the key to have these kind of specimens is to use it 48 hours after death. Take them out on block and flush them with saline, heparin, and 4% formalin to secure the distal part of all arteries and not to have any kind of blockage of post-mortem clots bilaterally. Here you can see 18 French sheet going into the main pulmonary artery, how we infuse the contrast into the superior vena cava. And in here, you can see microangioscopic image of how you see the pulmonary arteries and how you analyze the quality of the artery and the endothelium. Normally, you can find some damages in some specimens, and you won't need to do angioscopy for everything. But in this case, we use it to see that angioscopy can see endothelial damage. Sorry, everything is moving quickly. This will be the standardized clots that we use. They are radiopec using barium sulfate. And we use a Chandler wheel creation process. With the Chandler wheel, we can create a 1 centimeter in diameter and 10 centimeter in length clots with different kind of formation and histology compositions. And on this case, this would be an RBC-rich clot. It would be the posterior side of the clot. It is possible that you will find this as a pulmonary embolism clot, although the literature will specify the middle of this clot as the typical clot found in pulmonary embolism that is a mixture of fibrin and RBC. It is not difficult to remove ex vivo and in vitro. But if you want to do a proper testing of a catheter, you will need to put the catheter to a real test. And this will be the fibrin-rich clots that are extremely hard to first to remove, to break. And the catheter will have a very hard time performing its job. So we want to push the catheter to the limit so we know what kind of failure it will have in vitro, but never in a clinical setting where it will be a high mortality risk. Also, you see with this intravascular pressure measurement previous to embolizing the clot that is here. And we have a range from 14 to 18 millimeters of mercury without the clot inside, and 30 to 43 millimeters of mercury after the embolization. So we are proving the embolization was a success. And because the diameter is one centimeter, we can use the 26 French inferior vena cava sheet to embolize the clots. So the model use is a baseline contrasted DSA that we were obtained showing the patency of the distal pulmonary circulation. Selective pulmonary artery occlusion were created, and serial thrombectomy procedure were performed to recanalize the circulation. And the takeaway, the use of ex vivo human heart and lungs proved to be a suitable and replicable test bed for research and development of new age endovascular technology. I saw downstairs they also have some models, but the secret sauce to be as precise as you would want in a clinical setting, it will be by using cadaveric models that are exactly the same architectural anatomy that in a real human being, the texture of the arteries will remain the same as you would like in your clinical setting. And this allows you not only to see distally and proximally the length of the catheter and apply a failure mode and effect analysis, but also to put the catheter into the most heart of all the tests. So you will never encounter a fatal error during clinical procedure. So thank you so much. All right, very good. Justine is a pulmonary fellow from UCSF, Fresno, working with my good friend, Prabha Hegde. And she's going to talk about transexamic acid to prevent bleeding. And I'm actually very interested in seeing this, because these are frequent conversations amongst my group and many groups online, and if you're in some of the WhatsApp groups that the bronchoscopists are involved in, a frequent topic of discussion. So go right ahead. Yeah, thank you for the introduction. So like the title shares, I'll be talking about TXA that's applied pre-procedurally, meaning before we actually do a rigid bronchoscopy, to mechanically core through tumors. So I'm Justine, second year pulmonary critical care fellow at Fresno, and I have no financial disclosures to include. So a little bit on the background. As we know, lung cancer is a leading cause of cancer-related mortality. And amongst the many problems that lung cancer could cause, one of them is central airway obstruction, which can be potentially fatal if left untreated. So with central airway obstruction, what happens is you have tumor that's occluding the airway greater than 50% anywhere from the trachea down to the left main or down to the bronchus intermedius on the right side. There's a lot of different bronchoscopic interventions that are available to address central airway obstruction. And the fastest way to reestablish patency would be with rigid bronchoscopy. So what happens there is you have a rigid bronchoscope, and through direct visualization using a flexible bronchoscope, you basically have a beveled edge on the bronchoscope. So you use that to physically punch through the tumor that's creating the occlusion. And as you can imagine, tearing through tissue like that will cause some bleeding. And that is one of the major complications that is encountered when you use a rigid bronchoscopy to core through any tumor in the central airway. So TXA is something that's being used more frequently. It's oftentimes used to manage bleeding after a procedure has been done, for example, a transbronchial biopsy. It's also being used as a non-invasive measure to manage bleeding in cases of hemoptysis anywhere from pediatric patients all the way to patients in the ICU and those that are receiving it just for palliative measure. One of the theoretical complications of it that hasn't yet been described in literature is the event of systemic thromboembolic consequences. This is a video showing what mechanical coring looks like in an oscopy suite. So as you could see, it's not for the faint of heart. The rigid bronchoscope, for those that aren't familiar with it, is basically it's like a small metal pipe. And you're using that to punch through the tumor. And as you could see, it does a pretty good job re-establishing patency. But of course, there is bleeding, as you could tell. So at our practice, so my mentor, Dr. Hegde, he's a big fan of the rigid bronchoscope. And he has actually taken to applying TXA prior to the start of his procedures to mitigate the bleeding risk that he is already expecting to encounter as a result of the procedure. So our project's objectives were primarily to describe the degree of bleeding that we saw following pre-procedural TXA application, with secondary objectives being complication rates, such as requiring to remain intubated, any surgical intervention, blood transfusions, as well as the development of DVTs, since there is a theoretical risk, and of course, death as well. So this is a retrospective review of cases that occurred from 2015 through 2023. It's based out of a single institution, Tertiary Care Referral Center. All procedures are performed by a single interventional pulmonologist who was formally trained in this technique. And our inclusion criteria include in men and women over the age of 18, who are already scheduled for a rigid bronchoscopy for malignant tumors of the central airway. And we received informed consent from all our patients for all the potential interventions that may be encountered. But they were informed that this is for a rigid bronchoscopy. With regards to the TXA, so our solution comes in a one gram per 10 ml. And we spritz 10 ml of the topical TXA to the tumor in question, prior to mechanical coring and debulking. And we let it sit there for up to a minute. All DVT prophylaxis was held on the day of procedure. And Plavix was held five days prior to the procedure. And aspirin was usually held the day prior. So for degrees of bleeding, we described it as less than 50 ml being mild, 50 to 150 moderate, and severe being greater than 150. And the way we measure the bleeding, while we were in the endoscopy suite, was looking at the canister that you get from the suction and seeing how much volume was in there. So of course, there's a potential for a little bit of overestimation, since there's some saline that gets spritzed in there. There's a little bit of mucus and other bodily fluids. And the numbers were obtained in this chart review from looking at the procedure report. So we had a total of 43 patients that underwent true mechanical coring and debulking of malignant tumor. All cases were performed either in a hybrid operating room or in the endoscopy suite. There are many more patients who did undergo rigid bronchoscopies. But we only included those that had it for malignant tumor, meaning we excluded those that got it for tracheal stenosis related to prior intubations. The mean age of our patients was 64. And our mean pre-procedural INR was 1.2. So as expected, the majority of our cancer types are due to a lung primary, the leading being squamous cell, followed by adeno and small cell. And of the metastatic cancer types, the leading cause was thyroid malignancies with five cases, followed by colon endocarcinoma and neuroendocrine tumors of non-lung primary origin. So degrees of bleeding. So we had 38 of our 43 patients have mild bleeding. Three had moderate, and two had massive bleeding. So one of our two massive bleeding patients did require transfusion with one unit of PRBCs. Moderate bleeding was noted in small cell, squamous cell, as well as metastatic renal cell carcinoma, with metastatic renal cell being a cancer type that is expected to bleed. Massive bleeding was noted in lung adeno and neuroendocrine tumor. With regards to the location of the central airway obstruction, so the leading two causes were left main and right main. They were both an even number, followed by the trachea. And our massive and moderate bleeders had their tumor located primarily on the right side. So all of our tracheal tumors were actually categorized in the mild bleeding. As of note, we didn't see any DVTs in the 30 days following the procedure. This was evaluated by looking at all our patient cases to see if they had any DVT Doppler ultrasounds obtained due to clinical suspicion of DVT. And for those that did not have an ultrasound, we categorized them as not having a DVT since there was no clinical suspicion to raise concern for that. Seven of our patients remained on a ventilator. And two of these were due to persistent severity of bleeding, but they did end up getting extubated the following day. And the remainder of our patients were on the ventilator due to hypoxia or because they had received a stent, or they had a pre-planned tracheostomy tube that was placed, so they were still remaining on ventilator. So in our practice, we saw that the pre-procedural use of topical TXA didn't produce any major complications to speak of. And the majority of our patients who received mechanical coring did not have massive bleeding. In fact, they had mild bleeding, which was, again, described as being less than 50 ml. For those that remained intubated, two out of seven were for reasons related to bleeding, and the remainder was actually due to other causes. So I think the takeaway from here is that prophylactic use of topical TXA is a technique that is available to us to prevent bleeding complications in the study of mechanical coring or debulking of tumor. Of course, this was a single center. We didn't have a control group, since this is something that we use routinely for all our patients that undergo mechanical coring for tumor. But I think larger multi-center trials may be beneficial in describing if this, in fact, has an advantage over not. but in my mentor's experience, it has been successful and that's why he's gone with doing this for all our patients. So thank you everyone for coming to this session. Very good, very good, thank you. All right, so today I'm presenting a catheter-directed thrombolysis versus mechanical thrombectomy in treatment of acute pulmonary embolism, a systemic review and meta-analysis of dual-arm studies. The authors of this study are the pulmonary critical care faculty at the University of Toledo and members of the Internal Medicine Residency Program. And yeah, I'm Andrew Aberhamian and I'm Associate Chief Resident in Internal Medicine and aspiring Pulmonary Crit Fellow. No disclosures. All right, so concerning the background of this study. So current guidelines right now for either high-risk pulmonary embolism, which is defined as a hemodynamically unstable patient, or intermediate risk, which is a patient that is hemodynamically unstable, but shows RV dysfunction and elevated biomarkers, such as elevated troponin, elevated BMP, right now is to give systemic thrombolysis. However, over the past, I'd say decade, literature has come out supporting endovascular interventions, considers the PERFECT study, Seattle II, Ultima, for example. And endovascular intervention essentially consists of two different classes of therapy. One is catheter-directed thrombolysis, which is essentially an endovascular catheter that goes into the pulmonary artery and delivers a low-dose thrombolysis to the clot. And sometimes these include other methods in addition, such as ultrasound guided to break up the thrombus. And then the second method class is a mechanical thrombectomy. So this is typically a larger Bohr catheter that goes in and actually mechanically aspirates the clot. Now, guidance pertaining to these two different therapies is kind of left up. There's really no official guidance. It's kind of left up to the procedure operator, their clinical judgment, and then their experience as far as which device they want to choose to use. So that was kind of the motivation to doing this study. Our objectives is to assess differences in outcome between catheter-directed thrombolysis and mechanical thrombectomy. We chose three different outcomes. We have mortality, which we defined as procedure-related death, severe bleeding complication. That was defined by the gusto classification. So essentially it would be a blood loss that causes hemodynamic instability or an intracranial bleed, and then a length of stay in the intensive care unit. Methods. So we performed a comprehensive and systemic search of literature for dual-arm studies. So there have been single-arm studies, but there's no dual-arm studies that have been done. So we decided to go ahead and look at studies that compared these two interventions head-to-head. We used the PRISMA guidelines for study selection, data collection, and assessment. Cochrane Review Manager was used to conduct meta-analysis and extract data. And then we did assessment for risk bias. Here are studies. We looked at essentially screen 881. We came to a total of 458 patients that were completed in three retrospective studies. We had 266 patients that underwent catheter-directed thrombolysis, and 192 patients that underwent mechanical thrombectomy. The baseline characteristics of our population, as you can see here, for the catheter-directed thrombolysis group, 57 1⁄2, mechanical thrombectomy, 59 1⁄2, so essentially equivalent. Gender breakdown, again, equivalent, essentially for catheter-directed thrombolysis. It does appear the mechanical thrombectomy group is a little bit skewed female. We looked at our studies. Essentially, any patient that had a complete contraindication to thrombolysis underwent mechanical thrombectomy, so that could be the cause of that. Again, age and gender breakdown of our patients. Inclusion criteria. Again, all the studies we looked at were conducted in the United States. The patients from 2011 to 2021, as you see, there's a great diversity of CDT devices, only as far as I'm aware, Ecosonics only FDA-approved one for catheter-directed thrombolysis. Mechanical thrombectomy now, one study did look at a host of devices, but FloTriever, which is an FDA-approved device in that classification, was the most popular one used. So regarding our primary outcome of mortality, we did not find any statistical difference. CDT had a mortality rate of 2.3. Mechanical thrombectomy had a mortality rate of 3%. Moderate statistical heterogeneity was observed. Likely just because there was a very low death rate, so just by chance. In some studies, it clustered under one group in the mechanical thrombectomy, and other studies, it clustered in the other group. But again, no statistical difference was observed. Again, four spot of our data. Our next outcome, ICU length of stay, we did observe a statistical difference of approximately 24 hours. We assume this is likely due to catheter-directed thrombolysis is performed. It requires an additional observation period in the ICU, as opposed to mechanical thrombectomy, which is, if successful, the patient's hemodynamically stable. Again, here's a forced plot again of our data. And then the next one, secondary outcome of severe bleeding. We did not find any statistical difference between the two procedures. You know, one would maybe suspect that mechanical thrombectomy would have better outcomes. Now, this is, you know, I should mention, any, again, any patient that had a complete contraindication to bleeding was already moved, in our studies, into the mechanical thrombectomy group. So that's not to say that catheter-directed thrombolysis is safe for those patients. And here's a forced plot of our data for that. So regarding conclusions, we found that both catheter-directed thrombolysis and mechanical thrombectomy were equivalent regarding mortality rate in severe bleeding. You can argue that these are probably the most important outcomes regarding to safety and efficacy of the devices. And again, that is kind of with the caveat that mechanical thrombectomy is reserved for patients with a severe contraindication to thrombolysis. Mechanical thrombectomy did have a clear advantage over CDT pertaining to ICU length of stay, so pertaining to both cost. And then if we end up in a scenario with another pandemic where ICU beds are shorted, that is something to consider. Limitations. Again, there's only three retrospective studies that we looked at. A fourth study has come out. It did this April with around 1,500 patients. It had similar findings to what we found. There's no randomized control trials yet. Peerless, I think, is expected to complete, I think, next spring, looking at the Floetriever device versus catheter-directed thrombolysis. Again, device variability, that's just kind of a part of life. It is noted, too, a lot of the devices were not FDA approved in the catheter-directed thrombolysis group, and then device manufacturer funding. Any questions? Great. That was very good. So I have a, let's clap everybody. Clap, clap, clap. So today we're going to talk about the safety and efficacy of tracheobronchial stents in malignant airway obstruction. So this is a system make review. Sorry, interrupt. Are you a fellow, a resident, a pulmonary fellow? Yes, here I'm a chief resident. There you go. Thank you, I missed that. Okay, very good. All right. Just right there. And so we have no financial relationship to disclose. So tracheobronchial stents has been historically used to treat the malignant airway obstruction. So role is solely palliative. So improvement symptoms and quality of life, and there's really not much data regarding a safety and efficacy. So basically we collect all different kind of database, POMAD, OVAID, and Cochrane. So we collect until March 3rd of 2023. So only article published in English language were included. Abstract case report were excluded. Out of 76 study, 12 articles were selected. So results, so we have number of 1,041 patients and 1,028, they were malignant airway obstruction. And we have two retrospective study, eight prospective study, and two RCT. Both silicone and menthol stents were used in those studies. So four study reported statistic significant improvement of FEV1, FVC after stent placement. However, one study failed to report any significance. So all study reported improvement in dyspnea symptoms, but they used a very variable dyspnea score, unfortunately. And medium survival time is very wide. You can see from two to 84 months, because all study was performed in a very broad spectrum time. And medium survival time greatly depend on type of malignancy and the location of airway obstruction. So no death were reported as a result of stent placement. So most common complication will be a stent migration, of course, and the restenosis and tumor engrowth, retention of secretion, and granuloma formation. So there's a list of the study. You can see the early study was performed in the 1996, and the latest by ZEN on the 2022. There's a couple study they report on FEV1, FVC. There is statistics significant. And also, you can tell the medium survival rate was pretty broad, unfortunately. And we have different dyspnea score, but they do have the symptoms improvement after the stent placement. And you can tell the most common complication will be stent migration. And also, interestingly, there's a study from the dialer, and they mentioned there's arrhythmia, too. There's 0.3%, and definitely mucus plugging and tumor engrowth from the gel. You can see it's 13.9% of tumor engrowth in the stent. So basically, trichobronchial stent placement in a malignant area with obstruction improves symptoms, and also quality of life. There's no survival benefit was reported. However, one study reported that patient who received the radiation along with stent replacement had a better survival compared to only stenting. And stent placement is a relatively safe procedure with a low percentage of complication. That includes stent migration, restenosis, and tumor engrowth, granuloma formation, and retention of secretion. Yeah, thank you so much. Any questions? So, anybody, any questions? Oh, then I'll ask a question. So, when you did this, did you differentiate between central airways, large airways, and? No, actually, yeah, we cannot, because of limitation of study. We cannot really do a subgroup analysis on the different airway, different locational airway. But we do look at what's different tumor location. So, but no, but not large airway or small airway. Were you able to differentiate between metallic and silicone stent? Unfortunately, yes. Also, another great question. Unfortunately, yeah, due to the study limitation, yeah, we cannot. Okay, very good. All right, thank you so much. Yeah, have a great day. Thank you, Chen. Okay, so I'm gonna talk about laryngeal tracheal stenosis, retrospheric management of our studies and our patients. So, I have really nothing to disclose in terms of financial or any other things. So, the objectives of this lesson is to just analyze the effects of different interventions that we perform in patients with LTS and to see what kind of symptom relief these patients have with different endoscopic treatments. So, what we did is we looked at our patients with laryngeal tracheal stenosis to see how much of a long-lasting therapeutic effects they had after different interventions. So, over a year, we had like 21 patients which we looked at. It's not that much of a large number, but then again, remember, this is not a very common disease either. So, what we looked at is the number of endoscopic interventions that we did from the time of diagnosis, whether they had simple or complex stenosis, whether, and their grade based on CM, cotton mare classifications. And then we also checked their pre and post grades and the time between each intervention for which they were symptom free. So, and we looked if it was statistically significant when pertinent. And so, just to give a, this is just to revise, a cotton mare stenosis classification is for laryngeal tracheal stenosis. Grade one is up to 50% obstruction. Greater than 50% up to 70 is grade two. Grade three is greater than 70%. And grade four, literally you don't see any lumen in the airway. So, our patient characteristics, most of our patients were females. We just had one male patient. And the most common etiology was post intubation about 52%. The next most common was idiopathic. GERD contributed some. There was post tracheostomy about 14%. Most of the stenosis were complex about 67%. And the stenosis grade was mostly between the grade three, grade two, and grade one. We didn't really have anything. So, the treatments that we did, all of them received a flexible bronchoscopy. And the interventions were mostly done in either by suspension lungoscopy or rigid bronchoscopy or combination of things. So, balloon dilatation and steroid injections with triamcylone was done in all the patients, standing about 29%. Thermal interventions with APC laser were done in about 19 to 20% of the patients. And we had very little patients who we applied cryotherapy or mitomycin. And one of the patient went in for tracheal resection and about three of them got a tracheostomy eventually. So, the results, most of the diseases we encountered were complex tracheal stenosis, 14 patients versus seven. And most of the interventions were in grade three patients mostly. And post interventions, most of them attained a grade one luminal patency. And 19 out of the 21 patients had improvement in their dyspnea scores by MMRC. So, like I told you, all of these people received balloon dilatations and steroid injections. The shortest mean time between interventions was about 28 days. And for complex stenosis, for simple stenosis, it was more than 27 days. The longest time between intervention, for which they were disease-free, was about 438 days mean. And for complex stenosis, it was 569. And number of patients who really went into get tracheo-tracheal resection was one. And now from these results, what we really looked at was to see if any of these interventions made any difference to these people. So, when we did the steroid injections, the mean dose we looked at was about 40 and more than 40. And we did see that higher doses really did not cause any kind of difference in between the time between interventions or in decreasing the number of interventions required for these people, especially if it was complex. And the different thermal interventions that we use, mainly using a hybrid cautery knife to make radial incisions, or by using a laser to make some radial incisions, didn't make any kind of difference. What we found out is that it really did not change the time between interventions too much. And the number of interventions, now also really did not decrease, but we should remember the fact that this is just a small subset of patients. It's not a lot of patients. Now, 19 out of 21 patients had improvement in their voice quality, and almost all of them had improvement in their MMRC scores. And so the conclusion is that, what we found is whether you use a higher dose of steroid injections or lower dose, it really did not change time between interventions or granulation formation. And number of repeat interventions is expected, as expected, were more in complex patients with stenosis rather than with patients with simple stenosis. And none of the thermal interventions that we did did not decrease much in terms of the time between interventions, especially if you attained a grade one post-Cottonmire result. So the clinical implications is that, though there's a lot of things that we can do with thermal interventions, even just with simple LTS, just simple balloon dilatations can give them effective dyspnea scores and improvement in their voice. And as expected with complex LTS, if they're a surgical candidate, consider it if possible. Otherwise, even with balloon dilatations and thermal interventions, the recurrence rate is still very high. Thank you.

laryngotracheal stenosis

interventions

balloon dilation

steroid injections

thermal interventions

cryotherapy

tracheal resection