Podcast Transcript: Catheter Shapes: Basic to Challenging Cases

[Dr. Aaron Fritts]
Yeah. Fantastic. Well, these are great tips. I want to get into some of the questions for challenging cases. Sabeen wanted to know, left gastric and IMA can be tough to cath if there are stenoses. Any shape that can help? You know, the IMA, I kind of glossed over it when we talked about the mesenterics, but I think it's the most challenging vessel to catheterize, so if you guys have any tips for IMA, for like a GI bleed.

[Dr. Shelly Bhanot]
I mean, one that I've seen a couple of times it's worked for me is the RIM catheter, that nice curve can help back you into that origin.

[Dr. Kumar Madassery]
Yeah. The I and the M in the word RIM is for inferior mesenteric. The reason why that catheter has that name is because it was designed to help you with that. So some people use it. Actually, I know other specialists sometimes use that catheter for up and over aortic iliac alone, but that catheter has that nice, short, tight curve on it that when you're coming down that, that IMA comes just above the aortic iliac bifurcation. If you oblique your image when you do a run, you'll quite often see the origin if it's not heavily diseased or stenosis.

As you're coming down with that RIM, you're able to hook it. I'll usually start first with just a SOS. Quite often you'd be surprised if you just torque and angle as you come down, you'll be able to catch it. If that doesn't work, then I'll try something else. I would say if you're having trouble, truly, you can do a good DSA run in an oblique, a little bit off-center, and you might often find it, but between the SOS and the RIM, it's usually very feasible.

Now, sometimes it might be so tight that you got to get a glide wire or even a micro catheter through your base catheter to try to get in there, but those are step one, two, three for me on those, but they are challenging, and make sure it's actually there.

[Dr. Aaron Fritts]
Make sure it's there and make sure it's not occluded. If they had a CTA, take a look at the CTA, and you don't even need to mess around with the IMA if there's no bleed there.

[Dr. Kumar Madassery]
Exactly.

[Dr. Aaron Fritts]
I think it was old school teaching Kumar for me is, is like, you have to do three vessel. You know, celiac, SMA, IMA for all GI blades, but then CTA has got way better and it's like, no, you don't.

[Dr. Kumar Madassery]
No. That's exactly how I was taught. If you didn't check all of them, they'll say you didn't complete that procedure, yeah.

[Dr. Aaron Fritts]
Yeah. Now that CTAs are much better, and if you can actually see the bleed, there's no point in checking them unless you just don't see anything.

[Dr. Kumar Madassery]
Back in your time, Aaron, it was all wet film, so you had to wait. You had to go run process the film, hang it on the wall, get the dark goggles on.

[Dr. Aaron Fritts]
That's right. Well, we were there all night for one GI bleed.

[Dr. Kumar Madassery]
That's why you lost all your fingers, you know, back in the day.

[Dr. Aaron Fritts]
All right. Sabeen had some more questions for you, Kumar.

[Dr. Kumar Madassery]
Of course he did.

[Dr. Aaron Fritts]
He wants to know, what about tough up and over access for legs, like a really torturous bifurcation? Any tips for that?

[Dr. Kumar Madassery]
Yeah, Shelly, I don't know if you've been in any of the really tough up and over. Do you remember any cases like that?

[Dr. Shelly Bhanot]
Honestly, I feel like a majority of our cases doing an Omni flush, getting up and over with the Bentson or Glidewire through the Omni helps a lot. For the really difficult ones, I mean, very rarely I've seen you pull out the RIM catheter to get us up and over. Or sometimes if you're able to get a wire just a little bit over that arch and if you're having a hard time advancing the wire, getting more distally, then you switch to a crossing catheter to help you advance that wire to get more stable.

[Dr. Kumar Madassery]
Yeah, I think it depends on what you think is the reason why you're having trouble. If it's because of a steeped bifurcation versus a tortuous, heavily diseased bifurcation, that's going to be, I think, my mindset. I usually always start with an Omni. If I can get a wire down all the way up and over into the common femoral or SFA on the other side, and if the Omni is not going, then I switch to a straighter catheter, either a straight flush or a Glidecath, or sometimes like Shelly said, a crossing, like a recanalization support catheter because those are all smaller and smaller.

If it's for a really difficult case, then you can try a tip-deflecting sheath up and over to help you anchor, to get your wire support all the way down because sometimes all you can get up and over is a glide wire, which is not supportive for much of anything, so you might need something else. If it's super difficult and nothing's really working, what I'll do in those situations, I'll stick the contralateral common femoral artery retrograde. I'll keep a small 018 access. I'll get that wire up and I'll put a bareback snare. I'll grab the wire from the aorta. I'll bring it down.

Now I have a flossing access to then advance my catheter and sheath up and over. Then all I had was an 0.018 hole, like a micropuncture hole. I've done that a few times where nothing else is working and it's not a case where I can just go anti-grade down the leg. Otherwise, I'd prefer to do that anyway. Those are kind of my steps, is either get a smaller catheter, a more hydrophilic catheter to go up and over if I have good wire access, even a glide wire.

If not, switch to a support catheter and then put a stiffer wire through a support catheter because once you get a stiff Amplatz, super stiff, whatever, Lundquist, then usually anything will go over it as long as you practice riding the sheath over the dilator right before you get to the arch. That's the one thing that people still mess up. They'll get a wire, even a stiff wire, and they're advancing their sheath, and all of a sudden now, their wire goes up in the aorta. Usually, it's because that dilator is stiff and it's tapered down, so as you're pushing, it becomes a little bit of a spear, so it's going to push your wire at the bifurcation straight up.

When you get to that aortic arch, you just peel off the sheath from the dilator, let that go over. Once you get the sheath over, then you put the dilator back all the way. Those little things will help those difficult things, and Sabeen needs a lot of help in most of his cases.

[Dr. Aaron Fritts]
That's a good tip. Sabeen, I hope you're listening.

[Dr. Kumar Madassery]
Sabeen, just call Shelly, just FaceTime Shelly when you need help.

[Dr. Aaron Fritts]
That's great man, that’s great. All right. To finish up, we don't need to talk about flush catheters. Everybody knows when and how to use those. I mean, there's your pigtail and you got your SOS Omni flushes. We're typically using them in the aorta in the major vessels. I don't know. Any tips on flush catheters?

[Dr. Kumar Madassery]
Just remember, if you're using a flush catheter and then you put a wire through, especially glide wire or something like that, just remember that a lot of times, you may be going through the side holes. So there's been times where I've been called into cases because that's the fun part of training people is that something's stuck, something's not going right. That's because now you have a stiff wire somehow through a side hole of a catheter and now it's stuck and it's not going. Just be very mindful of thinking about where things are happening when you have a sidehole flush catheter.

Flush catheters, make sure that you remember that you can go really high on your pressure. Check the books, but you can go 900, you can go 1,000 psi on those because as you come down with different types of catheters when you're doing power injections, you have to lower your pressure. They're not built for that, but flush catheters are meant to give you an incredible jet stream effect of that contrast. That's what you should be using for your diagnostic angiograms, if you can, for the aorta, for the legs. The Omni flush, the straight flush, the pigtail flush, those are all catheters that are meant to give you great images compared to what you can with the others.

[Dr. Aaron Fritts]
Yeah. I've never seen that happen, Kumar, but that is good advice to go through a side hole but also just make sure you unfurl it before you pull it out, especially if you're in the heart. Really, if you're anywhere, you just want to get that wire all the way through, unfurl it before you remove that catheter.

[Dr. Kumar Madassery]
We'll use those pigtail flushes when we're going into the pulmonary arteries because sometimes, some people like to use the APT2 or create one with a pigtail flush with the back end of a Benson that's bent. When you're doing those kind of things, just be careful and remember where you are with those in terms of the loop.

[Dr. Aaron Fritts]
Oh, that's a great tip to create one with a regular–

[Dr. Kumar Madassery]
You know, you're talking about old school era. That's how our former predecessors all got trained. A lot of them, they take a Bentson wire at the back end of it, and they'd bend it a few centimeters from the origin, and you take your pigtail, you put that in your right atrium and then what they do is when they put the back end that's bent that pigtail now becomes bent so now they form like you know what we use now, like a APT2, which is basically an angled pigtail, and they use that to push and twist. I mean never push the wire out of the flush catheter obviously because now you have a sharp end, but that's what I was actually taught originally by one of my partners now when I was a resident was to use that method.

[Dr. Aaron Fritts]
That's great because some of these places don't even have the angled pigtails. What's the other one? It starts with a G.

[Dr. Kumar Madassery]
Grollman.

[Dr. Aaron Fritts]
Grollman, yeah. The Grollman or the–

[Dr. Kumar Madassery]
That's a tough thing because once a lot more people are using big large devices in the pulmonary is you want to be very careful because if you've done enough of these earlier on, you know what you have to watch out for when you get your catheter through one of the cords of the valves, and perforate things. Now you have pericardial fusion and death. You can avoid all that with the proper technique, and one of those is knowing how to use these catheters.

If you use just a Berenstein or something to get into the main pulmonary artery, that's probably okay to just do a quick picture but when you're putting in a 20 French, whatever device, you don't know what you went through, so that's why I think people have reverted back to remembering how to use a pigtail to get up there or a Swan or pushing a Fogarty over a wire after you've gotten access just to make sure before you put this big garden hose up there that you didn't cause a problem.

[Dr. Aaron Fritts]
That's a great point. Okay speaking of venous cases, the last two I wanted to talk about before we finish up are access catheters for TIPS and then we talked a little bit about adrenal vein sampling but we can touch on the right adrenal because it's where I talked about left adrenal. But for TIPS, I usually use just the multi-purpose or a hockey stick but sometimes the angle's tricky, right? Shelly, what's your go-to for TIPS getting into that right hepatic?

[Dr. Shelly Bhanot]
Yeah for the hepatic vein similarly, the MPA is our go-to. I have pretty reasonable success with that.

[Dr. Kumar Madassery]
Yeah, we'll go MPA as a primary thing that we have open for every even transjugular liver biopsy because you have to get to the same vein for those things. My method is usually MPA and by the way, MPB is like an MPA but it has side holes at the tip of it, but MPA is all you need for those situations. But if the MPA doesn't go, and there's some nuances to remember how to get in there and most often people aren't high enough because you're seeing the heart and you're thinking, "Oh, wait. I'm too high," but really you're not there yet because the hepatic confluence is probably a little higher.

If that doesn't work, then I'll go to Cobra, a C2, but the problem with that is when you get high up near that confluence, you're going to pop into the right atrium easily. My last go-to ditch effort that I'm not sure if many people use is a Launcher. It's a coronary catheter, but what it is is basically imagine a SOS but upside down, so basically when you put this catheter down and you form it in the IVC, now it comes with a catheter-like-- so it's got like a question mark with a flat line. So what happens is when you come up now with that catheter and it's got this question mark, as it's coming up towards the heart, that horizontal tip will catch the right hepatic vein. So that's my last go-to.

The problem with that is you can't really advance it into the hepatic vein. If nothing's working, I'll use that to get a wire down and then switch out to another but honestly, that saved me a few times when nothing else was working.

[Dr. Shelly Bhanot]
I remember in the beginning of the year, I was doing a transjugular liver biopsy and having a tough time getting into the right hepatic. That was such a nice case because we tried everything. We tried the MPA. We tried the Cobra. Everything just kept buckling out. I remember when he asked for the Launcher everyone in the room was like, "What?" and the tech came back, took a few minutes to find it, but it actually nicely seated us into the right hepatic. Then we were able to complete the case shortly thereafter.

[Dr. Kumar Madassery]
You know, one thing important for trainees is when we talked about walking around and looking at supplies. Walk around to the other specialty supplies too. A lot of things that everybody's adopted from IR has come from understanding the shapes and the lengths and the uses that other people are using. I mean, we learn in transradial how to use Sarahs and Jackys for viscerals because of the coronary catheters. That's where they're from. If you just rely on what you have, you'll never be able to improvise in situations, which is what our specialty kind of is about, so understanding what all is out there and when you can use it I've learned different things.

I’ve used the Penumbra select long catheter for UFEs from the radial because it just made sense for me from a neuro standpoint. They use it for that. It's long and it's nice. You never know what you're going to use but understand the shapes, why, how, I think that's important.

[Dr. Aaron Fritts]
Well, you just made a great point Kumar. I realize, this whole discussion has been centered around femoral access. It's all about where you're coming from. If you're coming from radial or you're coming from IJ, it's going to be a completely different angle. I mean, we're just talking about TIPS we're talking about coming from the IJ, but last one that I want to talk about is the right adrenal, which is maybe next to if not equal to the IMA as one of the most frustrating vessels to catheterize. What do y'all go to for a right adrenal?

[Dr. Kumar Madassery]
I mean, you can use either a SOS with some extra side holes. You can use a Cobra, a SIM. The problem with the SIM sometimes I think with that is and again, I preferentially and luckily don't have to do a lot of these, but the problem with the SIM sometimes, it gets you too far deep into it because of how long that that front end is, so I think having something else like a SOS or a Cobra may have a better shot when you make extra side holes because you need to be able to get the aspirate through it with a check flow or whatever else you use in there.

It depends again how far you are off your IVC wall being able to hook that. I think personally the right adrenal is probably harder than any other vein.

[Dr. Aaron Fritts]
It is frustrating and challenging, yeah.

[Dr. Kumar Madassery]
How about you? What are you using?

[Dr. Aaron Fritts]
Me? Thankfully I haven't had to do a right adrenal in a long time. It's similar to you. I passed that off to somebody else, but from what I remember it was always try a Cobra first, then SOS. That the algorithm.

[Dr. Kumar Madassery]
One of our one of our IR friends in Canada, Bao, he always talks about he puts a micro wire, micro catheter to offset the catheter so it's not stuck against the wall. He keeps that in there as a little balancing act so that you're actually within the lumen and have a lot better access in there.

[Dr. Aaron Fritts]
Okay. He just aspirates through the micro catheter?

[Dr. Kumar Madassery]
I think Bao just stares at it and somehow it works. He's a magician, but he has usually a tuohy in the back, so he has dual access approaches there.

[Dr. Aaron Fritts]
All right. Interesting. All right, guys. Well, that's a lots of great tips and tricks you guys provided. Thank you so much for coming on the show. Anything I left out?

[Dr. Kumar Madassery]
You know, I think it's interesting because not a lot of people think and I'm glad you guys took some time and effort to talk about catheters. If you think about what the process was probably like when Forssmann is putting a Foley catheter in his arm, or Ben Franklin put some kind of metal tube in his brother for bladder stones, and where we are now our daughter and you know Bill Cook became best friends to improvise on his plumbing interests, it's incredible where we are at now. I think it's important to take some time to understand the beauty of these products. There's a lot of effort that goes into these.

If you ever go visit any of these companies and see how these things are made, which a lot of people should do if you get into this, it's incredible what goes on when you just open this little thing and you know not me but somebody drops it and like, "Oh let's get me another one." You don't think about what all went into that process.

[Dr. Shelly Bhanot]
Also, all the time I have juniors being like wow, how do you know this, or how did you get there, and it's really just time. I can't impress enough on any juniors who might be listening to this podcast, feeling really overwhelmed with how many catheters we went over, that's just going to come with time and experience and doing more cases and seeing more cases. Everyone will get there.

[Dr. Aaron Fritts]
Yeah, and for the trainees as you get older is take the time. Like I remember some of my junior attendings and fellows, they would draw like what a Cobra looks like and what vessels it can access and really drew it on a whiteboard for me so I could visualize it instead of having to look it up in a textbook. The power of teaching goes a long way too. Just five minutes at the end of the case just saying, "Hey, do you know why we use that catheter?" Stuff like that. Thank you so much enjoy the rest of your Sunday. Thank you to our audience for tuning in again.

[Dr. Kumar Madassery]
Thanks so much everybody thanks for the wonderful AV technology support from everybody. Thanks, Sabeen, for staying off mic and camera. I'm sure hiding somewhere.