Supine PCNL (Ambulatory): Who? What? When? Why? How? - James F. Borin
James F. Borin, MD, Director of Endourology, NYU-Langone Medical Center, New York, New York, USA.
Moderator: Evan Goldfischer, MD, MBA
James Borin: Thank you. All right. I'm going to, first of all, try and keep on time. Second of all, I'm going to talk to you a little bit about the revolution and the evolution of percutaneous renal surgery. We all know that PCNL started off in the prone position and done under fluoroscopic guidance. The evolution of the technique is now we're using ultrasound guidance and we're using smaller scopes, mini-percs. We're using endoscopic guidance to guide the needle in. Starting about 20 years ago, supine PCNL first came to the forefront, a report by Valdivia from Spain in 1998 over 500 cases. And fast forward to 2011, and the Global PCNL Study with almost 6,000 patients looked at PCNLs from large centers around the country... around the world, and about 20% of them were done supine, very few in the United States. But more and more people are, have grasped the benefits of the supine position.
My personal journey started about 10 years ago. So, in 2006, we published our experience with endoscopic-guided PCNL. So we would put the patient in prone position with a split leg. We'd put a ureteroscope up. We would guide our needle in, and this allowed us to, number one, select the calyx that we wanted and, number two, to see that the needle was coming right through the center of the papilla. I did this for a few years, but I found that the prone position was a bit tedious. The anesthesiologist didn't like it. The nurses didn't like it with the split-leg table. There was a lot of equipment in the room, and I thought there's got to be an easier way to do this. And so then I started flipping the patients supine and sort of taught myself how to do it, and I've been doing it for the past decade and I haven't looked back. Many people have had a similar experience. Once they started doing it supine, they never looked back.
Okay. So who can have a supine PCNL? Well, basically anybody. Other than perhaps a horseshoe kidney, any patient that you can do in prone position, you can do in supine position. It's really good for patients who have concurrent urethral stones, if you're going to work on the other kidney or if they have an ipsilateral urethral stone, if they have bilateral stones or if they have bladder pathology.
So what is it? It's a puncture at the posterior axillary line. It can be done in a variety of different positions. It can be done in the complete supine position. It could be done with a small amount of elevation. It was classically described in the Galdakao Valdivia position, which is also known as a running man position, which kind of looks like this. One leg is straight, one leg is bent, patient's in stirrups. Their torso is little twisted and you get nice access to the flank.
When should it be done ambulatory? Well, I think, first of all, you to have good patient selection. If you're going to do this at an ambulatory surgery center, you want to make sure that the patient is going to be able to go home. You want a healthy patient who's not obese. You don't want any history of infections. You don't want infection stones. You don't want someone who's been pre-stented for a long period of time. Anything that you can do to reduce your chance of postoperative sepsis. You also want a smaller stone burden. A single stone less than 2.5 centimeters or several small stones less than a centimeter is ideally suited for this technique, and this is often ideally done with a mini-perc set.
I'm also going to talk to you a little bit about what I call the hybrid procedure, which is when a patient is sort of on the borderline between ureteroscopy and PCNL. So why do I do it? Well, number one, I tend to use endoscopic guidance, and it makes it a lot easier when the patient is already in supine position to just throw up a ureteroscope. You can actually see the needle coming right into the system. You can get direct lower pole access, but yes, you can also get upper pole access. One of the criticisms of the supine technique is people say you can't get into the upper pole. You can absolutely get into the upper pole. It's not that difficult.
A recent meta-analysis that was published about two months ago looked at about 1,500 patients, prone versus supine, and they found that the supine position was faster than prone and there was a 33% reduction in postoperative fevers. So I do think that it may be a better technique. There was no difference in stone-free rates or complications or anything else, but it's faster and maybe a little bit safer.
Okay. So if you have a stone 1.5 to 2.5 centimeters, could do ureteroscopy, could do PCNL. Well, there are going to be certain criteria, which are going to make you lean one way or the other. Patient is elderly, on anticoagulation, you're probably going to want to do ureteroscopy. If it's a very hard stone, it's a thin, healthy patient, that may lead you towards PCNL. But sometimes you get a combination of both. You get a young patient, but they have a soft stone, and maybe you could get away with ureteroscopy, maybe not. You may have a very hard stone, but the patient has comorbidities. So, again, you're sort of in this limbo of what's going to be best for the patient? What's going to get me in and out of the operating room the quickest?
So this is where I do what I call a hybrid procedure. And so this is an example case. So I consent the patient for ureteroscopy and PCNL. This was a patient, you can see in the panel on the left, he has about a six-millimeter stone in the lower pole of the left kidney, a 1.5 centimeter stone in the proximal right ureter, and it had been there for quite a while. He had pretty significant hydronephrosis, and I wasn't sure if I was going to be able to get a wire up.
So we put him in the modified Galdakao Valdivia position. You could see he's in stirrups. We've marked out the posterior axillary line, the 11th and the 12th rib, and then I bring in an ultrasound. I do the ultrasound before we even start the case. Number one, I want to make sure that I can see the kidney well, that the positioning is good. We can see there's hydronephrosis. That red arrow is pointing out that nice big stone, and also I'm looking above the kidney to make sure there's just skin and muscle on the way into the kidney. I'm want to make sure there's no bowel, there's no liver, there's no spleen. This way I know that if I'm going to do a fluoroscopically-guided puncture, I'm not going to hit anything bad.
We throw up a scope on the left side. We dust the stone in the lower pole. We don't leave a stent, just a wire, goes up and this ureteroscope comes out, and then we did a retrograde on the right. I got contrast passed the stone, but I could not get a wire up. Even with the ureteroscope, it was too tight to get a wire up. So normally when you're faced with this situation, you can either try and drill through that stone, but it may turn ugly. You can flip the patient over at that point and get access prone like you're used to, or you can stop the procedure, send the patient to interventional radiology and get a nephrostomy tube.
We don't do that. Patient's all ready, prepped and draped. Everything is ready. I have all my equipment ready. I just have them open a needle and I pop a needle right into the lower pole. I still actually could not even get a wire down because it was so tight. We dilated the tract to 24 French and passed a flexible cysto-nephroscope down and took care of the stone. The ultrasound is six weeks later. You could see there's no stones and only minimal hydro. So this was about a year or so ago. Now I'm using the mini-perc set, which gives you very nice access all over the kidney, minimal bleeding. And these patients can be done either with a stent for just a few days or potentially even completely tubeless.
So I think that doing this in an ambulatory setting is reasonable and feasible. You have to have good patient selection. And I like my idea of the hybrid procedure because sometimes you might find that a patient you think needs a PCNL, you can actually do your ureteroscopy. You dust the stone and you avoid it. But it's much worse to be in a situation where you're breaking a stone up and it's just not going, and you know you're going to have to come back. That's when you can do your PCNL. Everything is ready and you get the patient in and out in one procedure. Thank you.
Evan Goldfischer: Very nice talk. Just a couple of questions. So have you done any of these tubeless at all, leaving nothing, no stent, nothing, just closing the wound and sending them home?
James Borin: I have. I've not always been happy that I've done it because sometimes there's a little bit of bleeding. There's a clot. They have a little pain. It all goes away. I haven't had to re-intervene on anybody, but I lean towards leaving something, either a small nephrostomy overnight if I'm going to keep them overnight, 5-French ureteral catheter or a stent for just a few days.
Evan Goldfischer: Do you typically keep them overnight or is this something that can be done in an ASC, and like you said, sent home with a stent or small nephrostomy tube?
James Borin: I think if you're going to do this as an ambulatory case, I would definitely leave a tube because I think that's going to decrease your chances of having problems. Certainly, a stent on a string is what I often will do. They come back in a couple of days. They can remove it themselves or I'll remove it. I think that's going to be the safest thing to do in an ambulatory setting, particularly if you're doing a mini-perc. If you're going to do a micro-perc, that might be different, but for the standard mini-perc set or even a 24-French perc, I would definitely want to leave a stent.
Evan Goldfischer: Okay. And for the needle that you're using, if you're going retrograde to puncture the calyx, this Lawson needle, Hunter Hawkins, or what kind of needle you're using?
James Borin: Yeah, so I started off doing this with retrograde with the Lawson needle. You pass it right through the ureteroscope. This is a good way to learn the technique, learn the positioning, you can see it come out the flank. I've since switched. Now I get most of my access antegrade. I find that it's a little bit easier to target the calyx I want. There is some thought to using a laser, a 365-micron laser and you can laser right through the flank. The problem is right now the laser fibers are not radiopaque, so you can't see where they're going, but that is a development that people are working on. Actually, Dr. Clayman taught me that, and he's working on getting a radiopaque laser fiber so that you could actually see it come out the flank. And I think that would make the procedure even easier.
Evan Goldfischer: Sure. We have a question here.
Audience Member: When you stick antegrade, so are you sticking with ultrasound guidance or are you sticking with fluoroscopic guidance? Do you put your ureteroscope into the calyx and just try to stick onto the-
James Borin: Yeah, so we do a combination. I'll use ultrasound to figure out where the kidney is, what the angle is going to be. And sometimes I'll just use ultrasound, but often I'll put my ureteroscope up, and then I can select which calyx because sometimes the retrograde pyelogram doesn't tell the entire story. And you may think that the calyx is perfectly situated, but it's actually aiming the wrong way or it's more narrow. So, it's really nice, and I have found that sometimes when I get the ureteroscope up, I realize, Oh, the calyx I thought I was going to do, that's not going to be the best calyx. Sometimes the stone moves, and so you can select another calyx, and then I'll just puncture right onto my ureteroscope watching it come in.
Evan Goldfischer: We did get a couple of questions here. I'll just field them real fast. What is a mini-perc set? And this is just a nephroscope with a metal sheath that's reusable, so it's less disposables, and it comes in graduated sizes I think from anywhere from 12 to about 22-French to make a smaller hole in the kidney. And the set that I use is made by Karl Storz. I don't know if other companies make it as well, but I know Karl Storz makes a good one.