BackTable / VI / Podcast / Transcript #278

Podcast Transcript: Minimizing Complications for Lung Biopsies

with Dr. Robert Suh

In this episode, host Dr. Chris Beck interviews chest and interventional radiologist Dr. Robert Suh about his lung biopsy technique, including how he approaches pain management, and his take on the best way to seal the biopsy tract to prevent air leaks. You can read the full transcript below and listen to this episode here on BackTable.com.

(1) Lung Biopsy Setup

(2) Consenting for Lung Biopsy Procedures

(3) Cytopathology during the biopsy procedure

(4) Size Threshold to Biopsy Lung Nodules

(5) Managing Subpleural Lung Nodule Biopsies

(6) Characteristics of a Good Lung Biopsy Sample

(7) Ending the Biopsy Procedure: Blood Patch vs. Hydrogel Plug

(8) Managing Pneumothorax

(9) How to Use the BioSentry Device

(10) Pneumothorax: When to Watch and When to Treat

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[Dr. Christopher Beck]
Ladies and gentlemen, welcome to the BackTable Podcast. If you're a new listener, welcome. For all of our regular listeners, welcome back, and thank you, guys, for listening. You can find all previous episodes of the podcast on iTunes, Spotify, or really wherever you get your podcast. You can also check out the website, find all of our previous episodes and some additional content. That website is backtable.com, very easy to remember. Subscribe to the podcast, leave us a review, or reach out to us on one of our social media channels. Just let us know how we can make this podcast a better resource for our medical community and for you, and we're going to do our best to make that happen. We take the feedback really seriously, we read it all, trust me. Now, a quick word from our sponsor.

Today, we're going to be talking about techniques for a successful lung biopsy with Dr. Robert Suh. Dr. Suh is an IR doc out of UCLA. Rob, welcome to the show.

[Dr. Robert Suh]
Thank you very much, Chris. It's a pleasure to be here this morning.

[Dr. Christopher Beck]
Before we jump into the topic, Rob, will you just tell us about your background and about your current practice, and how it looks at UCLA?

[Dr. Robert Suh]
Yes so, it's kind of interesting because way back when, I did an interventional radiology fellowship, and I was looking for jobs at the time, but there really weren't the best jobs in the mid-'90s there for interventional radiologists, even though those were the only positions they were hiring for. So, my program director came up to me and said, "Hey, Rob, how about going and getting some extra chest training and coming back and being our section chief?" That's what I ended up doing, is going and getting the chest training. I was at Loma Linda for about two years, and eventually, I ended up back at UCLA where I did my second fellowship in chest and then it all started from there.

At UCLA, we've got a unique practice in that it's very organ-specific. A lot of the interventional radiology work gets done out of the cross-sectional sections as well as the interventional radiology section in general and so I've been able to focus my entire career pretty much in the chest and in the lung, both diagnostic and procedure-wise.

[Dr. Christopher Beck]
Really? So, the way it's split up is there's the thoracic section and so that's you and a couple of their intervention radiologists and some body radiologists where all the thoracic interventions are done by that group?

[Dr. Robert Suh]
Yes. What we did was not to exclude anybody. We took everybody on the general IR side that was interested in performing lung procedures as well as any thoracic radiologists who was doing high-end lung procedures and we made a group.

[Dr. Christopher Beck]
Cool. All right, that's a good way. So tell me, in a given week, what does the board look like for you or even if you want to break it down by day, week or month, what's your patient selection look like? What kind of cases are you guys doing?

[Dr. Robert Suh]
So for me personally, I've downsized my clinical practice only because I have additional academic and administrative responsibilities. So I'm pretty much doing procedures one to one and a half days and then clinic another half day, and then I do another day of diagnostic imaging, and then I have administrative days in the week. You know in order to address patient selection as well as operator skill and locale, because we've increasingly expanded into the outpatient arena with most of our procedures, we have a triage system. When it's your day to screen, you identify the patient needs and their typical ask for what they want for biopsy.

We also look at the outpatient center if it's appropriate for that and if it can be done by kind of the general pool of thoracic skillset or does it need to be done at a higher level skillset because, for instance, a 1 centimeter nodule there are few of us that do that, but not everybody in the lung group does those types of nodules. And so that's basically how we screen, so we make sure that it's appropriate for the patient and their lesion, has the target, the locale in terms of outpatient versus hospital, and also the operator.

[Dr. Christopher Beck]
When you say hospital versus outpatient, all the procedures or the lung biopsies are done as outpatients just whether you want to do it at the main UCLA campus versus one of the satellites where you might not have as many resources available?

[Dr. Robert Suh]
Correct and the hospital setting is both at Westwood, UCLA, and also Santa Monica.

[Dr. Christopher Beck]
Okay. Are there any patients that you guys need to see ahead of time to either talk with them or families or additional workup or are these patients kind of teed up and ready to go for biopsy?

[Dr. Robert Suh]
In general, we don't see patients beforehand in terms of a clinic visit unless they're, let's say an ablation or potential ablation patient. Then we may talk about the biopsy beforehand. But we generally see the patients before the procedure as in most practices. On occasion where patients or their families wanted to talk to the interventional radiologist to do the procedure who's doing the procedure, then we certainly can set that up in a clinic setting.

[Dr. Christopher Beck]
All right so the patient gets to you guys the day of the procedure. What does the workup look like as far as you already have your imaging, they've already been approved for a biopsy, so just what are some of the things you get them ready for either antibiotics-wise or sedation-wise?

(1) Lung Biopsy Setup

[Dr. Robert Suh]
So I think the first thing is you look at the board and what's going on and go through the cases. Sometimes we have residents and fellows as you can imagine. It's important to sit down and go through the target and the needs of the patient and the procedure, and then when I see the patient, it's really just running through the procedure, just what they're going to expect, and then I'd like to conclude that with maybe some expectations that I have for them in that I think one of the keys to have a successful procedure, and especially a lung biopsy, is to put the ball back into the patient's court, so to speak, so that they feel like that they have some sort of skin in the game.

So one of the last things I lead with is I ask them if they remember when they had their CAT scan or PET scan and if they remember that they took a big breath in and held it. Usually, they go, "Yeah, yeah, I remember that happened,” and I go, "Here, we just want you to take a small comfortable breath." Something that whether I ask them or our fellow or our technologist, just try to do it the same way each time. I think in many cases that sort of takes the, I guess the nervousness or the anxiety from the procedure because when they're laying, they're on the table, they're concentrating on something else and focusing on trying to do something else.

[Dr. Christopher Beck]
Yeah that's nice. So let's dig in a little bit into the breath-hold thing. Are you basically talking to your patients ahead of time in anticipation that you may have to do some breath-hold maneuvers throughout the case?

[Dr. Robert Suh]
In fact, we talk to all of them.

[Dr. Christopher Beck]
Yeah. About that.

[Dr. Robert Suh]
Yeah.

[Dr. Christopher Beck]
Do you do it on inspiration, expiration, or it depends on where the lesion ends up?

[Dr. Robert Suh]
No. Just a small breath in and hold it. It's like end tidal inspiration.

[Dr. Christopher Beck]
Okay. Are all the cases being done with moderate sedation? Local?

[Dr. Robert Suh]
Yes. So you know every so often there may be a need for general anesthesia or deep conscious sedation. But most of the time they're going to be moderate or mild conscious sedation.

[Dr. Christopher Beck]
Mild to moderate conscious sedation, keeping them light so they're not completely snowed and obviously not able to comply with the breath hold. You keep them a little bit light.

[Dr. Robert Suh]
Right. Of course, they're going to have to be awake or somewhat awake. In fact, over the years I've gotten to use less and less benzodiazepines and narcotics. So what I might do is start with something like one milligram of Versed, 50 mm of Fent, and then I give something like Toradol or IV acetaminophen to really give pain control if needed. But, the secret to having a successful lung biopsy is really knowing how to numb the parietal pleura.

[Dr. Christopher Beck]
Okay well what we want to do is uncover all the secrets. So let's hear about it.

[Dr. Robert Suh]
Yeah, so again, if you think about it, probably one of the most sensitive structures that the needle crosses when it's going percutaneously from the skin into the lung into the lesion is the parietal pleura because it's somatically innervated just as the skin is. The way that we numb up the pleura is that you bring the introducer needle or that 19 gauge coaxial needle we typically use for lung biopsy, and we just carefully bring it up to the pleura and you can see the target is what's called the extrapleural space and you'll see a little black band of fat there and that's just inside the endothoracic fascia, but outside or superficial to the parietal pleura.

The trick is to get your needle there and then go ahead and administer about 10 cc's of lidocaine or sometimes if it's a longer procedure like an ablation, we may put bupivacaine, but, again, 10 cc is the low minimum for me. I use at least 10 cc's if not a little bit more. Then once that's numb, it makes the procedure go so much easier because the patient doesn't feel the needle moving or tugging on the parietal pleura with respiration. As you know, the lung itself doesn't have somatic nerves, so once you're in the lung, they don't feel it anyways.

[Dr. Christopher Beck]
Once you have your needle in that position, once you inject the lidocaine like say you're putting down 10 ml of lidocaine or ropivacaine or bupivacaine, do you get that little lens shape fluid? You can see it on CT, where you get this little lens of fluid that's covering the parietal pleura.

[Dr. Robert Suh]
Yeah, perfect, Chris.

[Dr. Christopher Beck]
All right, good good. All right, I like it. So one of the other things you touched on, needle size. Whenever you guys do your biopsies, which kind of devices you're using, which needle size are you guys using?

[Dr. Robert Suh]
We're typically using a 19 gauge introducer needle, and 20 gauge sampling needle. These are the semi-automated type that you manually put out the capture chamber, and then it clicks and cuts off the sample. On occasion, if it's a large mass, and it's pretty safe, I'll go ahead and use a 17 gauge introducer needle with an 18 gauge core. But again, I think for things like ground glass lesions, 1-centimeter, 1.5-centimeter nodules, using the 17, 18 gauge does cause a bit of hemorrhage, whereas hemorrhage isn't too much of a problem, but it's the coughing that the hemorrhage causes that's a problem.

(2) Consenting for Lung Biopsy Procedures

[Dr. Christopher Beck]
One thing that I meant to mention, so I'll go back to it as far as your consent forms, whenever you consent your patients, I assume there's all the standard stuff, pain bleeding infection, risk of pneumothorax, risk of needing additional surgery or a chest tube or something. Do you guys discuss rare instances of stroke or death for the consent?

[Dr. Robert Suh]
You know, to go back in time, way back early in my career, I had two big complications, and they had to do a systemic air embolus. I kind of rethought, well, what should be in the consent, or how should you approach the consent at that time, and I even consulted with our risk management lawyers at UCLA. I think they gave some very practical advice, which I still hold to today, is that, I think, when you do an informed consent or you're talking about a procedure, it's really about making sure that the patient is informed about things that can commonly happen. Commonly is people's definitions vary a little bit, but things that you're most likely to anticipate or expect with the procedure.

Now, things like air embolism, death, stroke, all these kinds of things can certainly happen, but they're well under the 1%, if that, threshold. So the advice that I got is, well, you can mention them in passing, but I don't think when you give the numbers that in terms of how often or frequent these things happen, the patient is not going to say no to the procedure based on that. Again, you can mention these things in passing, but I generally don't.

(3) Cytopathology during the biopsy procedure

[Dr. Christopher Beck]
I think that's solid advice. I mean, there's such outliers, but it's like one of those things if you haven't had that complication, you probably know another interventionalist who's been through it, and it's just one of those things that I don't want to overly alarm the patient's for something that can be 999 times out of 1,000 a very routine procedure, but the same time, I was just curious about how you guys handled it. All right, so going back to the techniques, so we said typically 19 gauge introducer with 20 gauge needle. Do you guys have pathology on site to evaluate the sample or tell you whether or not you have adequate tissue, non-necrotic tissue something like that?

[Dr. Robert Suh]
When we do the biopsies in the outpatient in the hospital setting, we definitely have a cytopathologist on board for these cases. At Santa Monica, the outpatient site or center is just across the street, and so in those situations certainly you can have a cytopathologist come. But when we're in the true Outpatient Imaging and Intervention Center, then we don't have access to cytopathologist and so here basically the sample is placed formalin and then ensured that it gets to pathology, but there is no onsite evaluation of the tissue.

[Dr. Christopher Beck]
You can figure out which ones are going to be at the outpatient versus the hospital site. How do you triage which ones will need access to cyto and which ones won't?

[Dr. Robert Suh]
You know that's a good question, Chris, but we really don't use that as a form of triage as I mentioned in the algorithm that we use to this day. I suppose if something looks very necrotic or it's been biopsied multiple times without a diagnosis at the time of screening, you kind of know that. In those situations we may as another measure of screening, we may place that patient where cytopathology would be available.

[Dr. Christopher Beck]
In our practice, we don't have good access to cyto. We can get them on request and it creates a scheduling burden, but we do re-biopsies or if you think you're going to be in necrotic tissue and so you have a lot of opportunity to redirect the needle. But sometimes I think if you have a 1-centimeter nodule and your cytotech says, "Hey, we don't have good tissue." Some of the things that we biopsy are exceedingly small now what more can you do other than make a couple more passes and then keep your fingers crossed? I was just curious.

[Dr. Robert Suh]
No, I think you're right. I think we're being asked to get smaller and smaller. The ones that we often do, the higher skillset biopsies if you will, they're all routinely about a centimeter, centimeter and a half in tight locations. You're right, how much more tissue can I get safely?

(4) Size Threshold to Biopsy Lung Nodules

[Dr. Christopher Beck]
Is there any size threshold to which you guys will not biopsy?

[Dr. Robert Suh]
In general, no. Again, size threshold we've biopsied successfully 3 and 4-millimeter nodules. I think the rule of thumb for us is that if you can see the nodule on soft tissue windows, then it's probably fair game, but it's also where the nodule's located. A 5-millimeter nodule down by the diaphragm might be very tricky unless you have a very good patient with good breath-holding. Certainly, a 5-millimeter, 4-millimeter nodule up in the apex or in the upper lung may be very easy to get.

[Dr. Christopher Beck]
I want to talk a little bit more about size and location and basically how the lungs look. How do you approach these patients when you have a nodule that's FDG avid, it's up in the lung apex but it's just surrounded by emphysema. It just seems like it's emphysema and then the nodule. What y'alls approach to something like that?

[Dr. Robert Suh]
Well, you know in the old days you just try to find a little passageway to get in there to go through as best as we can say is normal lung as possible to minimize crossing the emphysematous cyst. Certainly, it's not worth going through a bullae because those are going to end in chronic air leaks that they'll never shut down. This is also where we can now collaborate with our interventional pulmonology colleagues because they can maybe access this from inside.

[Dr. Christopher Beck]
Y'all have a pretty good relationship with interventional pulmonologist?

[Dr. Robert Suh]
It's been great. I don't know what their numbers are, but obviously, they're not taking away from us because we're busier than ever. I think it's good for the system and good for patient care that you have multiple routes of tissue access.

(5) Managing Subpleural Lung Nodule Biopsies

[Dr. Christopher Beck]
Sure. Seems to be in terms of lung nodule biopsies, plenty of work to go around. This is another scenario. How about the nodule that it's not pleural based, but it's just right outside the pleura. One of the challenges that I see with those nodules is that if you go the shortest distance from skin to target, you have so little purchase within actual lung parenchyma. I'm interested to see do you approach that in a different way?

[Dr. Robert Suh]
I know there's a traditional teaching always go the shortest route possible or cross as little as lung as possible, but I think for truly subpleural lesions that are maybe one and a half to 2 centimeters or smaller, the better approach is to cross as much lung as you can in a tangential fashion. It was interesting because way back when Mike Wallace out of MD Anderson had a nice paper looking at yield and complications related to 2-centimeter and smaller lesions within the subpleural lung. What they found is simply that, if you come tangential and cross lung as much as lung as possible, the yields are substantially better than if you come at it the short, very perpendicular approach.

Interestingly enough, they had more complications with the long approach and I think there was another paper by Kho in radiology that showed that you're making a more oblong hole which is technically bigger than a rounder hole from a perpendicular approach, but I've not really seen that to bear out in real life. We always approach these types of areas and nodules in a tangential or long approach. What you really are striving for is to have the nodule and the needle move consistently as much as possible. If you go into the lung, and let's say you have 3 centimeters in a tangential approach to get to the nodule, as you're steering to that nodule, the tip and the nodule will move together more or less and you'll ensure needle tip and nodule consistency through respiration.

[Dr. Christopher Beck]
Along that vein, in terms of once you have your needle in position and ideally needle and nodule are moving together in respiration, so you're going to go take your passes. Between each pass, do you replace the stylet, and then are you imaging between passes?

[Dr. Robert Suh]
Again, we're taking samples with the same breath hole. As you scan, as you're moving your needle to the nodule and you have repetitive scanning, you start getting a feel for how that nodule and how the needle tip relationship becomes. With the breath holds, again, if they're good, then you're going to have a very consistent relationship. We breath hold, take the sample, and then we put the stylet back in, and then let the patient breathe obviously.

I don't really re-scan in between samples because the proof's in the needle. If you open the chamber and it looks like there's a core of tissue there that looks consistent with the target, then you know that you've gotten good samples or representative sample potentially. If for some reason, let's say you had good yield the first couple passes on a small nodule, then the third or fourth pass starts looking a little bloody and flaky, then in those situations, sure you should re-scan and make sure the needle didn't jump forward or it's completely off in terms of the angle or trajectory.

[Dr. Christopher Beck] Once you've made that first pass, that pristine look that you had at the nodule sometimes can be pretty obscure depending on if there's any bleeding around it. We have plenty of trainees who listen to the podcast, Rob, but can you unpack what a good biopsy sample might look like when you unsheathe it?

(6) Characteristics of a Good Lung Biopsy Sample

[Dr. Robert Suh]
I think what you're looking for is something that's whiteish or tan. When you unsheathe that sample, you're like, "Whoa." If you see a little tan core, maybe if it's a small nodule, let's say it's a 5-millimeter nodule, that tan core may be 5 millimeters long and then there may be some bloody tissue on the backside or the deep side of it, and then you feel pretty good.

We do touch prep now and not aspirations or FNAs and so sometimes how they do the touch prep, you may not get all of the cells or any cells onto the slide. It really is experience and sometimes just taking a leap of faith. If you're getting reasonable cores but they're not seeing anything on the touch preps, you take a few more cores and then you say, "Okay, I'm going to trust my judgment and my experience and leave it at that."

[Dr. Christopher Beck]
I think it also goes back to the point where you're in pathology says they don't see anything, but you're biopsying a 5-millimeter nodule, you've already made four passes. It's like, "Good luck trying to find that nodule again and have an improved positioning." So how many cores do you take roughly, ballpark?

[Dr. Robert Suh]
That's a really good question because I think the role of biopsy certainly has changed or evolved over the years. Before it was just simply to make a diagnosis and primarily it was for malignancy and in some cases just to confirm what looked like it would be a benign diagnosis. Now as everybody knows, it's the age of biomarkers. With biomarker sampling, you generally need more tissue than just to make a diagnosis. Here, again, there are many papers but really very few that tell you how many cores you need to take to get adequate sampling. In general, if I'm using the tissue retrieval device, then I'll generally minimum four, but I try to get between six and eight.

[Dr. Christopher Beck]
Nice, it's good tissue there.

[Dr. Robert Suh]
Again, I think if you look at some of the papers and what I've been able to extrapolate, if you assume about 90%, 95% cellularity of the target, then two 1-centimeter passes with an 18 gauge end hole biopsy device generally can run next generation sequencing. If you are using, for instance, a side hole 18 gauge gun, then it's about a 2 to 1, and if you're using a 19, 20 system with a 20 sampling, then it's roughly about 4 to 5, to 1 compared to the side. You're taking a reasonable amount given if you're using the smaller needle.

[Dr. Christopher Beck]
I think it's also a good opportunity to confer with your pathologist and it's always good to be checking your samples, ask them how much they need and then as you're giving them tissue you have that feedback with the pathology group. I always think it's good to collaborate with our pathology colleagues who always feel like you get what you get, and you don't say shit was the expression that one of my old attendings used say, but I think we're evolved past that now where if you just work with them to help get them the tissue, but still minimize the invasiveness of the procedure.

[Dr. Robert Suh]
No, I totally agree, Chris, it's really about communication and dialogue with your pathologist because at some places they're running so many immunohistochemistries off the slides that they exhaust the tissue just making the diagnosis. There has to be sort of tissue protocols in place in terms of how many slides are going to run for IHC versus what are you going to hold over for potential next generation sequencing if needed?

(7) Ending the Biopsy Procedure: Blood Patch vs. Hydrogel Plug

[Dr. Christopher Beck]
Yes, for sure. Once you've taken your samples, you have good tissue, either by pathology or just your Gestalt cases done, pull the needle, blood patch, anything else?

[Dr. Robert Suh]
Well, okay, the blood patch. So, I think majority of people just pull the needle out.

[Dr. Christopher Beck]
I think you're completely right.

[Dr. Robert Suh]
Then they just maybe put the patient to pend-in and hope for the best. Historically, I've used the blood patch and maybe it's because I did my residency and interventional radiology fellowship at Loma Linda, and one of the earliest if not the first papers on blood patching came out of Loma Linda by a guy named Ronald McCartney. But in '74 and '75, he described in two papers the blood patching technique in the first and then I think they ran a series of 50 patients in the second.

For very long, I've used the blood patch just because of how I was trained and my familiarity with it, and that all started to change in the mid-2000s. We participated in a trial for the hydrogel plug called Bio Seal back then. After the trial, the plug disappeared and then eventually resurfaced after it was FDA approved in 2013, and it was called BioSentry, not BioSeal anymore.

And so we did some work with the BioSentry and having some familiarity with it and what I started to do with that was to put it in every biopsy where we crossed lung, and then I kept the same follow-up routine in some patients for the first 50 I think, then I started to ratchet the observation time downwards. Today, I pretty much put the BioSentry in every patient, I keep the patient on the table for 3 to 5 minutes and then we do our posts and if there is no pneumothorax and it was an uncomplicated straightforward biopsy, I just send the patient home within 30 minutes, and I don't even get a chest X-ray.

[Dr. Christopher Beck]
Wow, that's nice. I really now have to dig into this. So BioSentry hydrogel, is this the same hydrogel material; I don't know if you're familiar with Terumo coils. They have a hydrogel coil. Is it a similar material?

[Dr. Robert Suh]
I'm not really familiar because I'm not really using some of those vascular products.

[Dr. Christopher Beck]
Okay, what exactly is the hydrogel? Is that too technical of a question?

[Dr. Robert Suh]
No, it's basically a polymer as anything else and it's really highly desiccated so it's like a little straw about 2.5 centimeters and you can prime it by putting a little saline or lidocaine in the well as you're deploying it but it's supposed to pick up the moisture from the tissues, and within five minutes, it should fully expand. It's about four times the volume, it grows in length as well as in width to plug that parenchymal but more importantly, the hole in the visceral pleura.

[Dr. Christopher Beck]
Does it go through just the introducer needle that you had in for the biopsy?

[Dr. Robert Suh]
Correct. That goes with the 19 gauge introducer but you can also use the 17 gauge introducer. There's a handle that you set the skin to pleural depth and then it pushes the plug down where ideally with a 2.5 centimeter plug, 2 centimeters is within the lung or the subpleural lung and then about 5 millimeters hangs out. As that grows it crosses both the lung and the pleura.

[Dr. Christopher Beck]
If you're deploying that hydrogel, can you still do the deployment? Because you mentioned if you have an uncomplicated biopsy, but let's say you have a biopsy where you have a very small pneumothorax that you see during the biopsy so you're getting your needle in position. It's not one of those ones where the lung is just totally deflating that you have to address on the table. This is a little small sliver of a pneumo, same deployment and everything.

(8) Managing Pneumothorax

[Dr. Robert Suh]
That's a great question. Yes, more or less. What you do is let's say you've taken all your samples and you're about to take the needle out and so before you take the needle out you should always scan the patient so you know what the lay of the land is. Instead of measuring from the skin to the pleura. If you had no pneumothorax what you do is you still measure skin to pleura but you have to measure to the visceral pleura.

If the lung is down 2 centimeters, then you're going to add let's say another 2 centimeters to that length. You'll still deploy it within the lung and it'll be hanging out into the pleural space where the pneumothorax or the air is also there. Then if it's large enough what you do is just put the coaxial needle or the introducer needle back into the plural space and simply aspirate it.

[Dr. Christopher Beck]
Yes, just suck it out as you're pulling it out.

[Dr. Robert Suh]
Right. I think people sometimes don't interpret pneumothorax the right way. They get bothered by the pneumothorax but, having a pneumothorax is relatively inconsequential. It's really whether or not you have an active air leak. By putting the introducer needle back into the plural space, aspirating on the air, when you feel the lungs sucking up against the needle, you can just wait 30 seconds, a minute, couple minutes, after that if you can't suck any air out, that means that you plugged the hole or the hole is sealed and it's a non-issue at that point.

[Dr. Christopher Beck]
The BioSentry device, can you work it in normal parenchyma in addition to if you have some really crummy emphysematous lungs towards the apices it's still fair game for deployment, no issues there?

[Dr. Robert Suh]
Yes, you can put it in obviously unhealthy lung or tissue but, I don't think anybody really knows if it works as well. I don't get the sense it does because, for instance, if you put it in a lot of emphysema or cystic lung, I know from our study that because the substrate of the lung is so abnormal, there's not a tight seal along that plug even though the plug has expanded and the air can still probably leak out because the cyst walls just aren't as tightly wrapped around the plug. In interstitial lung disease it's a little bit the same way with fibrosis not being more compliant lung. In those situations, those are patients that I would certainly watch longer and do chest x-rays more old school like our previous practice as opposed to what I do with the healthy straightforward cases.

[Dr. Christopher Beck]
Got you. Easy to use? I'm sure anyone can go and look up a picture. Is it bulky? Is it small? Is it just a little device that you go and throw in? Does it take 20 minutes to prep? I was just looking for ease of use because there's plenty of good devices out there but, if they become cumbersome as actually doing the procedure, it becomes more of a headache than a hindrance to actually getting it done.

(9) How to Use the BioSentry Device

[Dr. Robert Suh]
Right no, I get it because you don't want to make things more complicated in your daily life. I think it's a pretty easy to use device. It just simply comes with a little canister, that lure locks with a plug in it and it has a handle that you set the skin to pleural depth and then you lock it in and it's like I said, a pusher that goes over your coaxial needle and it abuts the skin. Then once it's flush with the skin then you pull the coaxial or introduce your needle up into the handle, and so it pushes the plug to the certain depth you want and then it basically unsheathe it at that location. With anything there is a little learning curve, but it's pretty small with this.

I think the things that people make errors with or operators have problems with is sometimes they push the plug in too deep and so it's completely embedded within the lung or they're not fast enough in terms of putting the plug in and it gets stuck in the needle and in part maybe they didn't flush the needle because there may have been some back bleeding and a stickiness as you know. I think one of the tricks is maybe flush the needle especially if you're starting to get some blood back into the cannula. What I'll do is I'll take a few millimeters off my calculated depth because as I mentioned before, the ideal location is two centimeters in with half a centimeter out, but you could do 50/50 if you wanted to. That way it sort of prevents you from putting it too deep.

[Dr. Christopher Beck]
Okay, the other thing I wanted to ask you about and this was what really grabbed my attention, because I'll just tell you in our practice whether we do blood patch routine complicated, it's three hours hold, one hour chest x-ray and then the a three hour chest x-ray and if that one looks good they can go. You're sending some of these patients home 30 minutes after biopsy, basically just enough to let the anesthesia wear off, no x-ray?

[Dr. Robert Suh]
That's correct.

[Dr. Christopher Beck]
That is great. All right, say you didn't have the BioSentry, what's the old school way of y'all's protocol?

[Dr. Robert Suh]
The way I used to practice and still some of us do because not everybody has gone my way. I have to say that this is something I do, but not everybody in the group practices the same way. How we used to do the follow up is like very much like what you've already elucidated. They go back to the observation, but they lay in that position or dependent side down for about an hour and a half, first chest x-ray, then a second chest x-ray at about three hours to four hours, somewhere in that period. Then if that looks okay, then the patients were allowed to go.

I think some of that follow up really harks back to some of the literature on pneumothorax after lung biopsy, given that most of the biopsy that had pneumothoraxes occurred in that first hour, but the far majority happened in the next three hours after that first hour. That's why people generally keep their patients three to four hours in the past. Despite having used the blood patch for so many years, we still had some delayed pneumothoraxes that showed up on that second chest x-ray and a few over the years after they went home. We looked at that as well, with our initial blood patch stuff.

So, I think in 124 consecutive patients, about 6 of them have delayed pneumothoraxes with the blood patch, but only one required a chest tube. If you see I guess the pneumothorax on the second chest x-ray or getting a little bit larger than you just naturally get another one after that.

(10) Pneumothorax: When to Watch and When to Treat

[Dr. Christopher Beck]
Yes. What is y'all's practice in terms of if you have a pneumothorax? I think it's always easy. It's like the pneumothorax where the patient's symptomatic and enlarging, it's like okay, no brainer put a chest tube. Can you walk me through your algorithm, which pneumothoraxes are getting watched and which pneumothoraxes are getting intervened?

[Dr. Robert Suh]
I think the biggest thing is when you have a large enough pneumothorax on the table, it's important to do something about it then. It saves you a lot of headache later because that way you don't rely on these indirect methods to ascertain whether or not you have an air leak. Indirect methods would be like repetitive chest x-rays. If you have a large enough pneumothorax on the table, simply put a catheter or put the introducer needle back in aspirate the air.

Like I said, once you get all the air out and the lung is sucking up against the needle, if you wait and observe and maybe scan a little bit if needed, but if you keep the patient on let's say for five minutes, you'll know if you've got an active air leak or not. If you don't have an active air leak, it's done and the air's out of the pleural space for the most part. Again, you're going to get good visceral parietal pleural acquisition when you put that patient dependent.

It's probably going to be a non-issue. If you do have active air leak, then by aspirating it helps you because now you could triage how fast that air leak is going. Now you could say, well, this person we got to put a chest tube in, but they'll do fine with a Heimlich versus I need to admit the patient and put them on wall suction because the air leak is so rapid.

[Dr. Christopher Beck]
Have you guys worked to differentiate the parenchymal, the blood patch from something called the plural blood patch where you do some plural injection with higher volume 50 to 60 ccs of the patient's blood?

[Dr. Robert Suh]
I know that technique was elaborated by the group out at Wisconsin with Fred Lee and I think you try anything that's going to help you in the long run, because we're all very busy and the last thing we want to do is keep adding to the bottom of our to-do list. Sometimes we'll do that. We'll put in 20 to 30 ccs of IV or fresh blood back into the pleural space. Again, I think it works better if you have less air in the plural space because then, of course, if let's say the patient is prone and you have a posterior lung puncture and let's say you got reasonable-size pneumothorax. You could put the blood in and then put the patient supine and get those plural surfaces to touch and so the blood's dependent in there, but you have a better chance of success in my opinion if you take all the air out because now you're coupling the blood plus the hydrostatic coupling between the visceral and parietal pleura. I think in any case, you could put those in or put the pleural blood in, but I would still recommend or advocate for taking the air out first.

[Dr. Christopher Beck]
Like you said, there's probably better opposition of the blood between the visceral and the parietal pleura if you've evacuated that potential space. Yes, completely agree. Is there anything, Rob, that I didn't bring up, as you said earlier like one of the secrets to a good case? Is there anything I didn't ask you about that you need to share with us or our audience?

[Dr. Robert Suh]
I just wanted to circle back to the use of the hydrogel plug because the group at Memorial Sloan, the paper by Maybody, they did look at that and found that the blood patch was non-inferior to the hydrogel plug, but I don't know. I just never felt as comfortable with the blood patching as I do with the hydrogel plug. Probably because the hydrogel stays where you put it, whereas the blood diffuses out of the track potentially. I use the plug on everybody and I think it's a good sauce. You can use it on everything.

[Dr. Christopher Beck]
All right, I like that.

[Dr. Robert Suh]
I don't know. I think meticulous technique, spend a little time on patient positioning. Don't settle for just prone and supine, but sometimes we'll bump up the side and it's not really just bumping up the side but sometimes we'll put in a very focal cushion to get the back to- let's say if the patient is prone, maybe you want to open up that rib space a little bit more so you could put a little small pillow or a towel ball I guess so that the patient extends and then the ribs and the spine open up better and it just allows you for better access.

[Dr. Christopher Beck]
I totally agree with that. I just want to second that for some of our younger audience and some of the trainees is that you do not have to settle for the positioning that your techs and nurses put the patient in when you walk into the room. Sometimes it's having the arm down, sometimes it's having the arm up. You never know that what just tweaks that rib in just the right way that something that was previously just hiding under the ninth rib all of a sudden it opens up and it's like light from the heavens that make the biopsy a thousand times easier. Just a little on the front end can make everything easier on the back end. I'm with you, Rob.

[Dr. Robert Suh]
Yes, for sure. Then the other thing is that I think a lot of people turn down biopsies because they look at the diagnostic and, oh no, it's behind the rib but these are all relative. You can position the patient to move things around as you said, that makes something that look inaccessible completely accessible, if you spend a little bit of time in working with the patient.

[Dr. Christopher Beck]
I think if you do these enough, you feel like they always look accessible on the CT, the pre-procedure scan, and then for whatever reason your first scan it's like they're always immediately behind the rib. [laughs] You always think what's the luck? It always feels like that. It's just negativity bias and what you remember. All right, Rob, thank you so much for coming on. We really appreciate it.

[Dr. Robert Suh]
All right. Thank you, Chris. It's been my pleasure. Happy holidays.

[Dr. Christopher Beck]
Thank you, sir. To our audience, thank you for listening. If you guys enjoy the podcast but want more, check out the show notes of this episode. Those are going to be able to be found at backtable.com. Remember, the show notes are where we can find that link for some free CME. Very nice. For others interested in supporting the show, [music] like, subscribe and share this podcast on social media or just go old school, tell somebody about it. That really works out. That wraps things up. We'll see you next time in the BackTable Podcast. Thanks again, Rob.

[Dr. Robert Suh]
Thank you

Podcast Contributors

Dr. Robert Suh

Dr. Robert Suh is a chest radiologist and interventional radiologist with UCLA in California.

Dr. Christopher Beck

Dr. Chris Beck is a practicing interventional radiologist with Regional Radiology Group in New Orleans.

Cite This Podcast

BackTable, LLC (Producer). (2023, January 3). Ep. 278 – Minimizing Complications for Lung Biopsies [Audio podcast]. Retrieved from https://www.backtable.com

Disclaimer: The Materials available on BackTable.com are for informational and educational purposes only and are not a substitute for the professional judgment of a healthcare professional in diagnosing and treating patients. The opinions expressed by participants of the BackTable Podcast belong solely to the participants, and do not necessarily reflect the views of BackTable.