BackTable / VI / Podcast / Transcript #97
Podcast Transcript: Nephrostomy Tube Placement: Basic to Advanced
with Dr. David Field
Dr. David Field from MedStar Georgetown University Hospital walks us through indications and technique for placement of Nephrostomy tubes, as well as some advanced tricks for the non-distended collecting system. You can read the full transcript below and listen to this episode here on BackTable.com.
Table of Contents
(1) Referrals for Nephrostomy Tube Placement
(2) Nephrostomy Tube Placement for Dilated Collecting System
(3) Nephrostomy Tube Placement for Non-Dilated Collecting System
(4) Complications of Non-Dilated Nephrostomy Tube Placement
(5) Post-Operative Care for Nephrostomy Tube Placement
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[Aaron Fritts]
Hello everyone and welcome to the BackTable podcast, your source for all things IR and endovascular. You can find all previous episodes of our podcast on iTunes, Spotify, and BackTable.com. This is Aaron Fritts as your host this week, and I'm very excited to introduce our guest today, Dr. David Field from MedStar Georgetown University Hospital. Welcome, David.
[David Field]
Thanks for having me.
[Aaron Fritts]
Before we dive into our topic today, just want to say a quick word from our sponsor RADPAD. RADPAD was developed by physicians for physicians, clinically proven radiation protection during digital subtraction angiography. Don't bet your career or your health on anything less. Trust RADPAD radiation protection shields for all your fluoro-guided interventions. See radpad.com for more information. Contact info@radpad.com for a free radiation evaluation and a no-brainer radiation protection cap and let them know you heard about it on the BackTable podcast.
[Aaron Fritts]
I'll let you introduce, give us a little bit of background about where you are with your practice, David.
[David Field]
Right. I have been at Georgetown since 2014, and I've grown to love all those urinary involved procedures, like prostate embolization. We do renal cryoablation as well. I've found that to be where I like to spend most of my time. Of course, we do a very broad scope of things at Georgetown, including a lot of interventional oncology, which I don't personally do, but we do quite a lot of, so it's a very broad practice and a lot of UFEs, as well. Dr. Spies is one of the forefathers of the UFE, so we do a lot of those there as well.
[Aaron Fritts]
Okay, so it's interesting. You guys kind of have little subspecialties amongst the department?
[David Field]
Yeah, each of us have our little niche. One of my partners likes to do all the venous work, and some people like to do the uterine artery, Dr. Spies and Dr. Caridi, who just left, and then one of my partners, Emmett Lynskey, does a whole bunch of portal venous hypertension work. He does more TIPS in a week, I think, than we did maybe in a whole year when we were fellows, so he'd really grown that practice a great deal.
[David Field]
We each have our own little niche.
[Aaron Fritts]
Yeah, that's impressive. For any listeners who are interested, we did have Alex Kim on a couple of months back to talk about his interventional oncology practice.
(1) Referrals for Nephrostomy Tube Placement
[Aaron Fritts]
And we also had Saher Sabri come on to talk about endo leak treatments, so also some great episodes. Anyway, let's dive into the topic today. We want to talk about placement of nephrostomy catheters. Just for, we have a lot of trainee listeners, can you talk through just the placement of a regular neph tube, the most common indications, and let's just start there with the most common indications and where are those referrals coming from?
[David Field]
Sure. The absolute most common indication is urinary obstruction, of course, whether that's from a stone or from a tumor. It doesn't really make a whole lot of difference for the fact that there is hydronephrosis, so most of the come from either urologists who have tried to place a stent from below and were unsuccessful, or from oncologists whose patients have developed hydronephrosis, or some of them come from the ER with urology on board as well for obstructing stones, and obviously with a great deal of variety in terms of urgency. The septic patient with an obstructing urinary stone, it's an emergency; the patient who has a hydronephrosis that has gotten slowly worse because of an obstructing pelvic tumor, it's not quite so urgent. What it comes down to, it's basically the same procedure.
[Aaron Fritts]
Both of those referrals come in from urology and maybe even the ER, GYN?
[David Field]
Yep. Not a lot from GYN, some from GYN onc, but mostly urology is probably the most common referral.
[David Field]
It's certainly where we are pretty good about taking patients in the middle of the night if they have a stone that they tried to get passed from below. I don't think they dump patients on us.
[Aaron Fritts]
Right, so when you get that referral, is it usually a phone call straight from the urologist or will they have the ER call you?
[David Field]
It's probably a mix of 50-50. Usually the urology resident will call our resident.
[Aaron Fritts]
Gotcha, because they've already seen the patient, worked him up, determined if--
[David Field]
They've already seen the patient. They know why or why not. Either they've already tried and they can't get it from below, or they know why they can't, or the patient is so sick that they can't tolerate more general anesthesia.
(2) Nephrostomy Tube Placement for Dilated Collecting System
[Aaron Fritts]
Sure. Okay, well so just, before we dive into the more advanced technique, I did want to quickly walk through the placement of just a very straightforward dilated collecting system neph tube. Maybe talk a little bit about single stick versus double stick technique and what you prefer.
[David Field]
I definitely prefer the single stick, but I think to sum it up, I remember being, certainly as a resident, a little bit intimidated by a percutaneous neph. I'm not really quite sure why, but when it comes down to it, it's really just a drain. The trick is that the target is often a little smaller than it would be for a, like an abcess drain for example, and it also is moving. It's a moving target because the patient is breathing, obviously, and so when the kidney is moving, it can be harder to stick. We do these really under, for a dilated system, under ultrasound guidance 99% of the time. I think it's very important to scan the patient in the room before the patient is prepped. A lot of times, techs will like to get their patient prepped and then you're left with a window there that is really of their choosing, so I really try to ultrasound the patient ahead of time and have a very good idea of the pathway and a very good idea of where we're going to stick on the skin for proceeding, certainly looking at prior imagining.
[David Field]
Almost all these patients have CTs ahead of time. Even if it's non-com, that's fine, but it's very important to know where the colon is, obviously, how far in you're going to have get to into the kidney, what the angle is, where the kidney is related to where the ribs are, and having that in your head before you even scan the patient is important.
[Aaron Fritts]
Right. We'll walk through the potential pitfalls and complications a little bit later, but with the pre-prep imaging, are you marking exactly where you think you're going to go in before they prep it out?
[David Field]
Yes. Before they prep, I will mark on the skin where I intend to start the needle, and I will mark off where I intend to put the probe so that they know where I need space, because nothing's more annoying than needing to ultrasound where there's a drape because you can't see through the drape, and you need a pretty big window in the draping, so I will let them know where I'm sticking and where the probe's going to be so it doesn't come back to bite you later.
[Aaron Fritts]
Okay. You mark your spot, they prep it, everything's ready, you walk in, put your gloves on, your drape. Walk through what equipment you're using. What's on your back table, and how you get the drain in from there.
[David Field]
Sure. We make sure we use a good high-quality ultrasound, obviously, first--the diagnostic ultrasound machine, not one that we'd use for, say, just like easy vascular access. I like to use the INRAD needles for this. I typically use their 21-gauge INRAD, and the INRAD needle has the scored stylet that has scoring over the last couple of centimeters so that it makes it very, very easy to see under ultrasound. Certainly if the patient is large, some people just don't image very well, it can be very easy to lose the tip of a needle in the retroperitoneal fat and using the INRAD needle is a huge help. The trick is seeing your needle the whole way and I'll see a lot of trainees who will start the needle, and advance, and advance, and then they'll look for it. If you don't see it all the way in, it's going to be hard to find later on.
[David Field]
That being said, once you have your needle in the retroperitoneal fat and you can see the kidney, you can see your target, at that point, it's important to go very definitively because next time the patient takes a breath, the posterior lower pole calyx, which is hopefully dilated, will move and then you can't see it. If you can see it, and you can see your needle, then it should be one definitive move through the cortex and into the calyx. We always do these from posterior inferior, or almost always, and then once I can visualize the tip of your needle in the calyx, I will take the stylet out and if I get urine back, I don't inject at that point. I put the wire in under fluoro and if the wire goes down what can only be the ureter, I don't inject at that point because certainly if the patient's infected, you don't want to over pressurize the system. There's really nowhere else the wire can be going, right?
[David Field]
Then I usually use an 018 Nitrex wire, or the 018 wire that comes in the AccuStick set, but I think the 018 Nitrex is just a little bit better. I try to get it down the ureter before I dilate up with the AccuStick. Sometimes it won't go, but at least make sure you have enough stiff wire in the renal pelvis so you can upsize.
[Aaron Fritts]
Really quick, before you upsize, for our trainees, what's the danger of overpressurizing that patient when you inject contrast?
[David Field]
Right, if the patient is infected and then you inject, overpressurizing the system, you can cause a great deal of bacteremia and sepsis and the patient can start rigoring right in front of your eyes.
[David Field]
It can go from bad to worse very quickly.
[Aaron Fritts]
Which we've probably all seen before. If you've done at least a few neph tubes, you've probably seen that happen.
[David Field]
That, or with biliary drains as well, obviously.I think it happens a little more often with biliary drains in my experience.
[Aaron Fritts]
Now you're at dilating.
[David Field]
Right. Under fluoro, get the AccuStick set in, keeping the wire very straight, and certainly the AccuStick set that we have, there's a radiopaque marker on it. The tip of the set actually sticks out a little farther, so if you overadvance it, it can make making the turn a little bit difficult. You've just have to make sure you get the metal part through the renal cortex before teeing off the first tee off and then get the final tee off into the renal pelvis. Then at that point, take everything out and you should get copious urine back. I will always inject at that time just enough to prove that the AccuStick set is in the renal pelvis and that you can get a good idea of your course through the renal parenchyma.
[Aaron Fritts]
Yeah, do you guys collect samples of the urine and send that off ever?
[David Field]
Absolutely, often. I will almost do it, especially if a patient is obstructed and infected definitely. The flip side of not overpressurizing the system if you decompress the system, then it's hard to work in, right? So you want to leave enough hydro that you can get your wire in and get your tube in behind it. If it's really dilated, I'll send a sample once we get the AccuStick set in, or you can also just send it off the tube after you get the tube in.
[Aaron Fritts]
True, yeah. Real quick, a lot of times that urine can be a little bit blood tinged, right, because of all the manipulation. For the new IR or the trainee, that was one thing that was kind of hard to get used to is how much blood is worrisome, you know?
[David Field]
Yeah, right. It takes a very little bit of blood to make urine look pretty red, so Kool-Aid is absolutely fine. If it's frank blood, it's a problem, and, of course, if it’s pulsatile, it’s also not the best. If you get your tube in and it's just a venous bleed, it'll probably tamponade.
[David Field]
If you've made one stick with a 21-gauge needle, the chances of really having a significant bleed are pretty low.
[Aaron Fritts]
Right, right. All right, well great. Then you take your picture, right? You always want that final picture.
[David Field]
Right, you give the AccuStick a second, and just try to make sure that you are in the renal pelvis, and at that point, then you have to get your wire in, and we just use an Amplatz wire, and once the floppy coil is in the renal pelvis, then it's just a matter of dilating and then just put in usually an 8 1/2 French, a Cook multipurpose drain.
[Aaron Fritts]
Okay. If it's like a frank pus, do you ever upsize?
[David Field]
Yeah, sometimes we'll go to 10. But, of course, every time you dilate, take out the dilator and put in the next stylet, you're also going to expose the bloodstream to the pus there, right? That's a little more manipulation, and it just depends. It's easy to upsize later.
[David Field]
I wouldn't really go past the 10 to a French.
[Aaron Fritts]
Okay, so that's a great walkthrough. Let's take a step back real quick in terms of, and this applies to both basic and a more advanced technique that we're going to talk about here in a little bit, is approaching these patients, you already talked a little bit about pre-procedure imaging, but what labs are essential coags, and then what are you doing for antibiotics?
[David Field]
Yeah. Well, we used to give Cipro, but that's not the greatest anymore, so we've been giving ceftriaxone immediately pre-procedurally these days, which has been working well. Yeah, obviously, you need to know their recent coags. I think the latest SIR guidelines suggest that an IR of 1.8 or lower is fine, so above that we would correct with FFP or whatever needs to be corrected. platelets 50 or higher is fine.
[Aaron Fritts]
What about a patient who's been on aspirin?
[David Field]
Baby aspirin, don't care, but certainly 325 aspirin or Plavix or any of the platelet inhibitors, optimally, would be a five-day hold, but obviously if the patient is infected, you can't wait that long, so you have to balance the emergent nature of the procedure with how sick they are.
[David Field]
I also wanted to say if you make a stick with your 21-gauge needle and you think you're in, but you're not, the tendency is to inject a lot of contrast. I've seen a lot of trainees who will inject some when it's not a calyx. I certainly did this a lot. I would be like, "Oh, maybe it is. Maybe I'll inject some more and maybe it'll look like a calyx." It's fine to puff your needle back very gently, but if you inject a lot of contrast trying to show that you're in and you're really not, it's just going to make things harder for you down the road because there's invariably a little bit of air in with the contrast so it's going to make ultrasound very hard, fluoroscopically, it's going to obscure things. So, I think it's important to, if you're not in, just go back to ultrasound, try it again, and not inject too much contrast into the perinephric space.
[Aaron Fritts]
Yeah, I think that's really good advice because I've seen it'll just look like a bomb went off and especially with the non-dilated collective system, which we're about to get to, but like you said, there's a big stone in there and you're injecting contrast and then you have no idea where you're going.
[David Field]
Right, and then later one, you can be in, you can be injecting, but you won't be able to see it.
(3) Nephrostomy Tube Placement for Non-Dilated Collecting System
[Aaron Fritts]
Right, right. Let's talk a little bit about this is kind of a technique that you've worked on over the last several years in terms of getting good success at getting into a non-dilated collecting system, because I, myself, and I've seen others struggle and struggle and struggle, and before you know it, you have two hours and an hour of fluoro time and you're still not in. And you think, “Do I keep going?” You know you've got a whole list of procedures to follow and you're already behind, and you think, “When do I call it quits?”
[Aaron Fritts]
I'm hoping that you can help some of us out there who struggle with that and to try and prevent that with some technique. First of all, tell us some common scenarios where a non-dilated collecting system needs a neph tube.
[David Field]
Right, sure. The patients that we do the most on are patients who have stagnant calculi who are needing percutaneous access for stone removal by urology. Also quite commonly, and probably increasingly commonly, are patients who need complete urinary diversion, patients who have had Fournier’s gangrene and have leakage from a damaged urethra, patients who have a pelvic malignancy and who have a physical vaginal fistula that just will never heal because they're just going to keep leaking urine through it, patients who have had pelvic radiation because of a tumor and have radiation cystitis and have just continuing hematuria. All of these patients need urinary diversion and often we will get asked to do that. It's really almost never an emergency, it's just these are chronic problems that just need to be fixed.
[Aaron Fritts]
Right, so it's usually preoperative or perioperative having maybe something to do with, or related to, a tumor, I guess.
[David Field]
Just patients whose quality of life is such that their perineum is continually bathed in urine and it's just skin breakdown, or they have such bad bleeding from their bladder. Some of the patients have bladder tumors, so the urokinase and then urine just makes them continually bleed. It's never bleeding enough that they are unstable, but these patients need continual transfusion just to maintain their blood loss.
[David Field]
If you can remove the urine bathing the tumor, that often will help it stop. Of course, these patients have completely nondilated systems, and that makes it very hard to get into.
[Aaron Fritts]
Right, so let's talk about that. How do you approach these guys?
[David Field]
The way to get in them more easily is to make them a: easier to see, and b: bigger. At Georgetown, we have a Phillips system that has a guidance software package attached to it, like XperGuide CT, and we basically can do an on-table DynaCT and then the cone beam CT image that is generated allows you to pick a target calyx and the entry point on the skin, and you thereby know that there's nothing in between the skin and the calyx, and it will create the exact fluoroscopic angle under which to stick the system. Once you've selected your target, and your skin entry, the C-arm goes to a specific position and then on the fluoro screen, there is a target where you start your needle and then under fluoro, you just advance it straight down along the beam. About halfway through, the machine will rotate to the other 90-degree angle and then you can follow your needle to the target. Does that make sense?
[Aaron Fritts]
Yeah, so are you trying to stick right down to the stone? Is that what you're trying to do?
[David Field]
Right, well we pick the target. If it's a stone, then it's an easy target, right, but if it's a nondilated system for urinary diversion, I will give the patient IV contrast and I usually give them about 90 milliliters, if it's unilateral. If it's bilateral, I will usually give about 75 on one side and then have to give some more on the second side. But if you give the patient the IV contrast with a 10 milligram chaser of Lasix, the system will pump up right under your eyes.
[David Field]
As long as the patient is ready to go, then you can give the IV contrast, give the Lasix, and then you do your DynaCT and you will see the calyx light up and pump up because with the Lasix you actually have a much better target.
[Aaron Fritts]
I see. I gotcha. They're already prepped and draped and then you give the IV contrast, give the Lasix, and then how long do you usually wait before you do your cone beam CT?
[David Field]
I usually wait about five minutes. Yeah, but during that five minutes, intermittently fluoro, and if you start to see the calyx appear under fluoro then you go ahead and do it.
[Aaron Fritts]
Then you work on like a timer? Are you pressed for time after that because-
[David Field]
No, not in that instance because once you've done the DynaCT, you have your target.
[David Field]
You can define your target based on the image you get from that fluoroscopic CT, and even if the contrast empties out of the calyx later, you can still use it as a target because you're just asking the computer to define that target for you.
[Aaron Fritts]
I see, and if the patient moves, does that matter?
[David Field]
Well yeah, if the patient moves, it's a hassle. We will often do these with anesthesia. The patient's prone, so they always like to tube the patient, so they can do apnea, they can do breath holds.
[David Field]
That actually makes it much easier, so we do the breath hold right before the DynaCT. They're motionless. Then as you move the needle, you also ask the anesthesiologist for apnea and that makes it much, much easier.
[Aaron Fritts]
All right. Yeah, so those are great tips. Are you using ultrasound at all in those cases?
[David Field]
In those cases, often not.
[Aaron Fritts]
It's just pure CT and fluoro?
[David Field]
Exactly. I will often ultrasound ahead of time just to get more information about where the kidney is related to anything, or to give a general area to be prepped, but often just the fluoroscopic guidance that is provided by that Phillips system.
[David Field]
I know that when Dr. Kim was on the podcast a few weeks ago, he talked about doing angio ablation, and this is the same system that he uses for guidance for the ablation probe into the liver.
[Aaron Fritts]
Ideal for just basically helping to direct your needle exactly where it needs to go without any guess work basically is what it sounds like.
[David Field]
Exactly. There's no guesswork. You know where you're going to end up, you know where you're going to start, and you know that there's nothing in the way, right?
[Aaron Fritts]
In the way, right. No colon in the way.
[David Field]
Yeah, exactly. If you think that there's pleura in the way, you can just bring your skin entry point more inferiorly. The tricky part is just following the dotted line, basically, that the software produces under fluoro.
[David Field]
You still use an NRAD needle just because that's what we use, but we drive with a hemostat under fluoro, and that's really the only difficult part is staying along the path that the software has determined.
(4) Complications of Non-Dilated Nephrostomy Tube Placement
[Aaron Fritts]
Okay. Are there any pitfalls to deal with, like where you, obviously, want to keep an eye on your angle, could be aware of the pathway the tube needs to make even though it might be the shortest pathway, the angle might not be right. Can you speak to that a little bit?
[David Field]
Right. Well, I think that's mostly important when you're doing access for a urologist who wants to do stone removal either the next day or the same day because they like to come in a really direct path from the skin to the kidney. Whereas if you're doing something under ultrasound, your tendency is to have a little bit of an inferior to superior angle on your needle. When you're doing it for a urologist, you want to think about how they want to be looking at the kidney when they do the stone removal and try to come in as direct a path as possible.
[Aaron Fritts]
Gotcha. That makes sense. We already talked a little bit about bleeding and we talked a little bit about avoiding crossing the pleura, what happens if you do cross the pleura? Have you had that happen, and what do you do in that case?
[David Field]
I personally have not. I have not had that happen. I think it's really important to be cognizant of where it is. If you're below the tenth rib, you should be fine.
[Aaron Fritts]
Yeah, and then any other complications to worry about?
[David Field]
Other than bleeding and sepsis, nothing. These people are not typically infected, right, because they're non-dilated. We really just worry about bleeding.
[Aaron Fritts]
Right, and I guess, ever seen a situation where there's been injury? We talked about trying to avoid the colon, but injury to any other organs?
[David Field]
Yeah, I've not. I've not seen that personally, and I think that really is one of the main points of safety when you're doing a nephrostomy of any sort is being very cognitive of where the colon is and where other things are, and under an ultrasound, it can be a little bit hard to see a colon that is potentially decompressed in that area.
[David Field]
Looking at the pre-procedural imaging is very important and also just being cognizant of what is between the skin and the kidney.
[Aaron Fritts]
Right, and with that, a lot of times morbidly obese patients it's almost impossible to use ultrasound or it's extremely limited. In those cases, even for the dilated kidney, do you guys find yourselves using DynaCT more often?
[David Field]
Occasionally, but it's really mostly for the non-dilated patients, because it involves anesthesia and it involves just a little more of a hassle, right?
[David Field]
A lot of people don't have this capability, right? So we should probably talk about how you can do nondilated systems if you don't have the magic of the software that will tell you how to guide your needle. You basically have to predate yourself. What I did before we got this system was ultrasound the patient first, and plan a path into the kidney just under ultrasound, making sure there's nothing in the way, making sure that I'm hitting the right part of the kidney, and then I will mark on the skin where I'm planning to stick. Then I would actually put the C-arm in position so that I can stick down that path, so you tilt a little a little LAO if you're doing a left-sided stick.
[David Field]
At that point, with everything ready to go, like the 21-gauge needle in hand, that's when I give the contrast and the Lasix, and at that point, you do have a very short, or a relatively short, window of time during which you're able to stick because you do it directly under fluoro. So, you just intermittent fluoro until you see the calyx appear. It will get a little darker, a little bigger, and then you have to stick definitively. It's really just the same thing. I will fine tune the patch by basically putting like a hemostat at the point I know I'm going to start at on the skin, and then moving the II so that directly overlies the dilated and newly apparent, opacified calyx. Then I just stick straight down the beam, parallel to the beam, into that calyx.
[Aaron Fritts]
I gotcha. Head on, right down the barrel basically.
[David Field]
Exactly. You're looking right down the needle. Exactly.
[David Field]
I will always take a still shot as well because then you get a much better picture of what you're sticking, but then actually stick under fluoro. Then, once you think you have made it there, then you have to bring the II to the lateral position and you can tell whether you are through and through potentially, or you're not quite there yet, but you'll be very close.
[Aaron Fritts]
Right, then you have to use your triangulation.
[David Field]
Exactly. Exactly, you're basically doing what the fancy Philip's software does for you.
[David Field]
You can do it yourself. In that case, you do have to move relatively quickly because the contrast will empty out of the collecting system.
[Aaron Fritts]
Have you ever had to re-inject?
[David Field]
No, but certainly have not been in when the contrast has gone away and, in that case, you know you're close, you know your needle is close and then you just have to figure out exactly where you are and then re-stick and inject a little bit of contrast, again, not injecting too much not to obscure your path. It's definitely more challenging than having the software do it for you.
[Aaron Fritts]
Right. I mean, obviously, a lot of people don't have fancy software.
[David Field]
Right, exactly. As long as you have fluoro and the trick really is the IV contrast and the Lasix to puff it up. I'll give 10 milligrams usually per side.
[Aaron Fritts]
Okay. In terms of the next step, once you get that needle where it needs to go, do you ever inject air?
[David Field]
Sometimes, especially if there's obscuration by previous attempts, that certainly helps. It also helps if you are not quite sure where you are and it looks like you may not be in. But air, obviously, if non-dependent, whereas contrast is heavier, right, and the patient is prone, so if you inject contrast it's going to preferentially fill anterior calyces as opposed to posterior calyces.
[David Field]
Of course, you want to be in a posterior calyx, so air is certainly good for that.
[Aaron Fritts]
When you already have contrast in there?
[David Field]
Yeah, when you already have contrast. It's good for negative contrast.
[Aaron Fritts]
There have been times where I've stuck down straight down on a stone, for example, right? If the stone fills the collecting system and I know I'm in, I can't get my wire to pass because I can't get around the crunchy stone. What do you do in those kinds of issues?
[David Field]
Just keep trying, and use different wires. As my mentor used to say when I was training with him, "If something doesn't work, don't keep trying it. Try something else." Just try a different wire. If you have enough stiff wire to get your AccuStick set in, then you can almost always get it. 018 Nitrex, I think is really good for getting past stones. You can also, if you are able to once you're in, you can pump up the collecting system by just injecting more saline or contrast, or both, right, dilute contrast. You don't want to obscure your wire but you can also, if you know that you're in, you can pump it up.
[Aaron Fritts]
Yeah, I think I've tried that with saline just so I don't obscure it. And just in case you're not all the way, you'll get that resistance. It kind of feels similar to doing an arthrogram.
[Aaron Fritts]
Yeah, it's like you kind of know if you're in or not if you get that resistance or not. I would always try a little bit of saline to just create some space around the stone and then try the wire again real quick.
[David Field]
Right, right. A couple of times I've actually gotten through a stone with like the NRAD needle or whatever we're using, and if you're doing it for urology access, they don't usually mind that because you're just basically leaving them a pathway to get to the stone. They just need solid access to the bladder, right, so if you go through a stone, they're fine with that. I certainly would say before I do any PERC access for lithotripsy, I always make sure that I know exactly where the urologist wants to approach the stone to make sure everybody's on the same page about the access point.
[Aaron Fritts]
That's a very good point. Starting out, I made the mistake of not calling the urologist ahead of time and I would just put it where I thought they were wanting to go based on experience, and then I got some angry phone calls. I've talked to IRs about this. Everybody has a different opinion on it, but I just made a policy like any of these stone ones for lithotripsy. I just call the urologist ahead of time and say, "Hey, I'm looking at the CT right now. Where would you like this access?", and usually they really appreciate you asking them.
[David Field]
Absolutely, and you develop relationships with them and then everybody's much happier.
[Aaron Fritts]
Yeah, for sure. I think I had one or two cases early on in my career, first starting out, where I put it in the wrong place and I got thrown under the bus to the patient, too.
[Aaron Fritts]
The patient was not happy because the urologist said, "Hey, the IR doc put the tube in the wrong place. You've got to have this over again.
(5) Post-Operative Care for Nephrostomy Tube Placement
[Aaron Fritts]
That's never good either. I think that covers it in terms of the procedure itself and any kind of perils and pitfalls, getting access, how about postoperative care? Once you get the tube in, you get them cleaned up. What's to follow?
[David Field]
Well, we obviously check them. We follow them while they're in house, make sure they're not bleeding and that their urine clears over time, that their output is what it should be, and then they are, typically these are permanent tubes, so they will come for an exchange every three months. A lot of these patients need diversion because they have radiation cystitis, or they have a pelvic tumor, or what have you, and need really permanent diversion. We have been occluding the ureters either at the same time we get the first access, or a couple of weeks later. The moment you have access to the collecting system, it's quite straightforward. We've been using this EOS plug that is made by ArtVentive, and it's actually a vascular plug, but it comes in an 11-millimeter size that works very well for occluding ureters. It's very easy to deploy. We basically get an Amplatz wire down the ureter and it goes in very nicely through a destination sheath, one of the terminal destination sheaths, a six French sheath, and we get that sheath right down two-thirds of the way down the ureter and then deploy this plug through the sheath.
[David Field]
It's a two-step process of deployment and it has this, almost like a spring that opens up and it's PTFE covered so they're quite good at occluding ureters.
[Aaron Fritts]
That's just for the purpose of chronic diversion?
[David Field]
Yeah, patients who have non-healing wounds because they have urinary leakage or perineal wounds and who we know are going to need really permanent urinary diversion. Neph tubes will divert most of the flow, right, but there's still the path of least resistance flow down the ureters for some of the urine, so if simple diversion is not enough, then ureteral occlusion can finish the job.
[David Field]
Typically, one plug per side, and it's a 20-minute thing and you're done.
[Aaron Fritts]
Before the plugs, were people using coils for that?
[David Field]
We were doing this thing where we would cut the pinkie off of a glove and shove it down with an Amplatz wire, it didn't work very well. It was very hard to deploy. Took a much bigger sheath, so the EOS plug is very much much easier. Yeah.
[Aaron Fritts]
Yeah. Oh yeah, so the last question I have, what should the expectation be in terms of the timing of clearing of the urine? When should you be worried when it doesn't clear?
[David Field]
Yeah. If it's not clearing, I would make sure that you're checking the hemoglobin, right, and then see if the hemoglobin is falling at all. If it's not falling, then I wouldn't be too worried about it, but if there's a steady drop, then I'd be worried about a pseudoaneurysm or something like that.
[Aaron Fritts]
Yeah, you'd just do a CTA?
[David Field]
Or sometimes we'll do, if we're really worried, you'd do an actual renal angiography. You've got to pull the tube out, like in the biliary. IIn almost all cases, it clears after a couple of days.
[Aaron Fritts]
Okay. Well, that was pretty much it. Do you have questions for me? Do you have anything to add for the trainee or any young people out there, any other pitfalls to avoid?
[David Field]
I typically will do standard nephrostomies with the 21-gauge needle and then an 018 wire and then the conversion to an 035 wire. I think it would be fine to do a very dilated perc neph in a not very fat patient with a 19-gauge NRAD needle and then go straight to an 035 system, especially if you are really in a rush, right? So you don't necessarily have to go conversion of a 018 to 035, but certainly that's the way I trained, and probably you as well.
[Aaron Fritts]
Yeah. I mean, the obese patient with that dilator, I mean, you've got to have a steady track to go over. In a skinny patient, and they're septic, and you just want to get a tube in really quick, I agree with you.
[Aaron Fritts]
All right, well that about wraps things up and we really appreciate having you on, David.
[David Field]
Thanks for having me.
[Aaron Fritts]
Definitely good to catch up. For our listeners, again, you can find all prior episodes on iTunes, on Spotify, Stitcher, basically any podcast platform that's out there, we have our podcast on, so it should be pretty easy to find. You can also look on our website, backtable.com and we actually have a new web app that has a lot of procedure information, including how to place a nephrostomy tube, so please check that out, and we're adding to it weekly. Thanks again, and everybody have a great day.
Podcast Contributors
Dr. David Field
Dr. David Field is a practicing Interventional Radiologist at MedStar Georgetown University Hospital in Washington DC.
Dr. Aaron Fritts
Dr. Aaron Fritts is a Co-Founder of BackTable and a practicing interventional radiologist in Dallas, Texas.
Cite This Podcast
BackTable, LLC (Producer). (2020, November 30). Ep. 97 – Nephrostomy Tube Placement: Basic to Advanced [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.