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Creation of a Radial-Cephalic Arteriovenous Fistula

Nahel Elias, MD, FACS, Sahael Stapleton, MD
Massachusetts General Hospital

Transcription

INTRODUCTION

Hello my name is Nahel Elias. I'm a transplant surgeon at Massachusetts General Hospital. The procedure today is an arteriovenous fistula at the wrist, so it's a radial artery to cephalic vein or radiocephalic AV fistula creation. The procedure consists of dissecting through the skin, identifying the cephalic vein, and dissecting it for an adequate distance. Then mobilizing it towards the artery, identifying the radial artery, and- also dissecting it for an adequate distance. Ligating the vein distally and cutting it just proximal to the ligature. then mobilizing the vein towards the artery, and performing the anastomosis between the vein to the artery in an end-to-side fashion. Following that, we'll close the skin after assuring hemostasis, and that's the end of the procedure.

CHAPTER 1

Left wrist AV fistula- he’s positioned - he’s marked. So this is the- cephalic vein as identified by palpation. This is the radial artery. And we’re going to make an incision curvilinear to extend it if we need an extra length on the cephalic vein to get to the artery. This is the numbing medicine. A pinch and a burn.

We’re making an incision through the skin. You can go down to 25 on the Bovie, please. A straight. J please. So I don’t know if you can see the vein- it’s over here. I'll take an Ohms retractor, please.

And Debakey's, please. So now that we identified the cephalic vein, we're going to encircle it and mobilize it for an adequate distance to bring it over to the artery. Can I have a vessel loop please? So this is the cephalic vein of the wrist. We’re going to mobilize it for- a good length, so we can get it down to the artery. Stay closer to the vein. Yes. Mobilize a little further distal, on top of the vein. Or superficial to the vein. Yes. If you turn your tips away from the vein, it's a bit safer. It may be easier for you if you retract the vein with this, and then use your scissors, so that will be your counter-traction. This looks good enough. Alright, let me just get- there's a little bit of a bleeder right here. Right here. We'll need a quick buzz. Let me just retract this, and if you can retract… Let's grab that tissue there. Perfect. So getting a good length on this vein is essential to mobilize it to the artery, and not have it under tension- when it's under tension tends to- narrow or occlude. So if you hold this for a sec. That's the reason I make my incision curvilinear, this way if you want to get more length on it, you can extend it that way. Do you ever have to superficialize these ones? Very rarely on the forearm. In the upper arm, patients with a larger-size arm, and they- they may have to have that. Sometimes there's- a thin layer of fascia within the subcutaneous tissue holding the vein down, and then you definitely have to superficialize it. But the cephalic vein in the forearm tends to be superficial.

Let's go deep through the tissue here. So if you hold this up, you'll just go straight down. Yes, and this is where you go, kind of- longitudinal. Okay. So a curvilinear for the cephalic, and a longitudinal for the radial? Yes. Well essentially, for the subcutaneous tissue, you’re going longitudinal for both, right? Along the vessel. This way it’s less likely that you’re injuring any structures in there. It's more comfortable when the patient is under local anesthesia. You can divide this a little more. So the artery is over here. I'm feeling it underneath this. Yep, here it is. So if you grab this. See the artery? Yes. So go through there. Quick buzz right there. Can I have the other forceps, the right angle forceps? So grab the tissue opposite to me. So similarly, you want to dissect the vessel for an adequate distance. Now we don't need to mobilize it as much, so the dis- careful of the skin- we don't need to mobilize as much of a distance, but- Hold on to this. A good distance will make it easier to- clamp it. So we'll take another vessel loop please. See this artery is relatively smallish in size. And a SNaP. And that's an important reason to do the Allen's test before you do this because you could be mobilize- taking away significant amount of the blood flow into this artery- diverting it into the vein. I'll take another vessel loop please? Actually, why don't you dissect this. Tie that off, or? Yeah, there's a small branch, why don't we tie it off. I'll take a 3-0 tie, please, or do you... 4-0 or smaller, please. 4-0 tie, please. So with a vessel this small, very little tension on this- on the tie. When you're tying, but also when you're cutting. Scissors. Okay, bring the knot down. Don't retract the vessel too much when you’re tying. So use 2 vessel loops on the artery. And depending- SNaP, please. Depending on the size of the artery, you may have to double loop these vessel loops, but this is a smaller artery that I think just retracting it like will do. And I use these to occlude it and retract it. This way you have minimal trauma to the artery when you're doing this. Okay. We’ll tie it over here, we should be fine.

3-0 silk tie, please. Let me just retract for you. This way you get all the length you can on the vein. Yes.

So at this point, important things to think of is make sure the vein is not twisted. So an easy way to do that is to dilate the vein. We flush it with hep-saline, which is also useful to dilate the vein. So I start with a forceps or a SNaP to dilate the vein. Hep-saline, please? So why don't you occlude the- just kind of almost like a tourniquet on the arm. This is a straight enough - short enough cord? Yes. So you don’t mark it or anything with a marker? Yeah, yeah we don't need to. Doesn't look like it's done. So this is what you want to make sure is not twisted in here. Looks pretty good. Schwartz clip please. The other thing about the length of the vein, when you have this much length on it, a little bit of a twist- you know if you have like 45 or even up to 90 degrees- not a big problem. Okay. Make sense? And we see how dilating it makes it really have a good size. I like to do this so we don't have to put a retractor underneath, but it looks like we will need it. I'll take the Ohm's retractor please. This is going to be a bit in our way.

CHAPTER 2

So I'm going to cut it at an angle to spatulate- you got the iris scissors? So we're going to make an arteriotomy over here and anastomose these 2 together. I'll take the beaver blade- white towels actually first. And one more. So you see the length of this. Once you see the flash of blood, that means you're in the lumen. Okay. Knife down. We’ll take the iris scissors next. I'm going to make sure it's not bleeding, so that means your vessel loops are holding- properly. Then extend the- arteriotomy, only on the- one side, make sure you don’t get the back wall. Hep-saline please. Oh, there’s a little bit of bleeding from the distal end, so I'm going to retract this a little bit tighter. This is where sometimes double looping the vessel loop is beneficial. It looks like we got it. And you know it’s the distal end, you just saw it coming from that direction? Yeah, so when you dry it, you see where the blood is coming from. The other- helpful thing you can do is flush it with hep-saline, and then you'll see where it's coming from. Okay. And either way, when you retract one end, you're putting traction on both in a way. Okay. This looks like a long enough anastomosis.

So this is long enough that we can actually sew it from outside. Sometimes I sew the back wall from inside, but we can do it either way with this one because we have enough length on the vein. Yeah, just grab the other end. Now opposite to me, I'm going to do the heel first. And you know we’ll- we’ll take another stitch like this please. You want to tie it or snap it first? I'm just going to snap it. And what we’re going to do is we’ll have you start the back wall. I'll take a shod please. So you can take it outside in, in the 2. Have the vein inside out on the artery. Yes. Take the same needle. Take it inside out on the artery. You can almost do it forehand I think better. Yep. So you noticed on my side, I did inside-out then inside-out with the other needle, but if you go outside-in on one side, you can do inside-out with the other. So you see this is a small artery. So just be careful in the size of the bite you take. Yes, perfect- take it. So we can tie that. Wet my hands please. My left. More, more, more, more, more, more, more, more, more- thank you. Shod please. I always put a sliding knot in my first 2, so- you get it all the way down. Shod this, then we're going to sew with this. So you're going to swing this on the other side of the vein. This way you can see your loop holes nice. Outside-in on the vein, inside-out on the artery. Straightforward vascular anastomosis. First corner stitch especially if you’re not at the- the corner, you do it in 2, which makes a lot of sense. Freer in the lumen. I got it - just got to get the wall open without the… So one thing you can do is just put a- one of your jaws like that, and then- go ahead, try that. I can do it from here for you if you want. It's maybe easier. Yep. Yes, nice. Your next stitch or the next one, you should be able to start taking it in one. And as we go further from the corner, I will be retracting. By me retracting, I will be opening the artery for you. There’s a little cuff, is that okay? Yeah, that's fine. We have a long vein - we have a… yes. Nice. Take slightly bigger bites on the artery is okay. Okay. Remember we did a linear arteriotomy, and we’re replacing it with a cylinderic structure, right, the vein. So the artery is going to be bigger, in diameter, so if you take some of the- diameter out by your suture, it's not a compromise. Nope, you're good. Can you see what I'm doing? I'm pushing the wall of the vein into the lumen. So my forceps is essentially preventing you from back-walling right now. Don’t move your hand, please. Yes. Straight through across. The less you manipulate the vessels, the better. Do you find that for the vein as well, or is it more… More for the artery, but yeah, veins can take it. Corner in two. So because we haven't tied it down, you could almost take it in one, it's not that much more of a problem. One thing may be easier is for me to take it this way, but see how your angle is? Try to take it. Okay, I think we can swing it back. We'll start with the vein, with the the corner stitch first. We'll take this one underneath, or? Yes. So take the end of it, and pass the end of it. Hold onto this needle. Just going to check the vessels, make sure- so, I don't think we took the back wall. The other important thing to check is we didn't narrow the lumen coming down. Okay. So if you grab the vein open. That's good. And this is nice and wide. It's good. Now, if I tie this… So if you grab the vein under tension. Just a minimum amount. So if the vein is shorter and you don't have the ability to twist it over and sew it from outside, you could sew it from inside the lumen, so I'd be sewing both sides from my side, but in that situation, I usually do the corner stitch as a U-stitch, and not tie it down. Tend to be tougher too, if you tie it down to be able to- take that all the way. If you're doing one stitch, and you're not doing a U-stitch at the, and you're not tying it down, you want to make sure when you tie it at the end, you don't tie it too tight because you could purse-string it, and minimize the flow in the vein Okay. Kind of like- I was watching that liver transplant. Yes, when we do the venous anastomosis on the portal vein, we leave it loose. I was surprised how loose it actually was. Yes. You can always make it tighter, right? You can take stitches in it and narrow it, but you don't want to loosen it, and you don’t want it too tight, then you have to redo it. So again, I’m taking the corner in two. Don’t move your hand, please. He's helping me sewing. You want the jewelers there? Yes, I've got them right here. Just at the corner, I don't mind using the- the right angle so I can- put it in the lumen. Put the tip in the lumen, and- see it a little better. Wet my hands, please. You can cut your corner stitch.

So first you open the vein, but as you saw, the vein didn't have back bleed because of valves- Schwartz clip back to you. So we will take the distal corner, which still has arterial flow, we'll see how it- the vein… So we have a nice distal- the distal is open, the proximal is open. By doing that, it kind of like gently refills it as opposed to forcefully? Yeah, it’s still- I mean an arterial- the radial artery has good flow from, you know when you have a normal Allen’s test from both sides. And you can feel a nice thrill to it. And you see, we retracted the artery quite a bit that now, I mean the vein is not under tension, and it's straightened out. Maybe we can take out this band to minimize- the angulation there. Do you have the doppler probe open? And see by occluding it proximally, you lose the thrill, which means that it's a single outflow, which is essential for these. The longer the distance of the vein with single outflow, without branching, the better the fistula will be, the better it will mature. Okay. Vessel loops back.

See when I occlude it. You lose the diastolic flow. You will have some systolic flow- which means there's no flow in it. Okay. Perfect.

CHAPTER 3

This looks hemostatic. Looks pretty good. Good. So, I usually- the trouble with these, if you have any bleeding, is the vein is so thin that it will be occluded by hematoma that I prefer not to close it completely watertight with two layers or anything like that, so I just do interrupted, deep dermals in the skin. Okay. I use Vicryl, with a small needle, and just do them about 3 to 4 mm apart- inverted, deep dermals. Do you have the 4-0 popoffs? and Adsons with teeth? Do you do like a Histoacryl closure then? No, I just do Steris, and this way- and don’t put the Steris all the way. Sutures scis please. So essentially a deep dermal. just approximating and leaving a little bit of a- separation in between the sutures. Still, look at the skin. It comes together nicely. Yep. At least if it bleeds tonight, it won’t compress and clot the fistula- that’s the point. And sometimes you have little bleeding from the skin or the sub-Q, Some patients who are uremic, their platelets aren’t working well - all that factors in. So you see how I separate them? So if there’s a hematoma, I will escape through. Release our popoff. Needle down. And you just do the same thing from your end. Sure- I'll take another stitch, please. And now we feel the thrill very nicely over here. So the deep dermal inverted- you're starting the sub-Q essentially, get some of the deep dermis. Yep, leave the epidermis apart. And then cross-over superficial and come deep. And it's important to avoid the vein when you're sewing these. That would be a problem. The attending would be frustrated. A little bigger bite. I find it easier to do subcuticular or deep dermal, when you're pulling the opposite side, when you're everting the stitch, it's easier for you to- let me just make sure this is on the right… So you see we got both ends, one on each side of the loop- that's not right, so we got to bring this underneath. Yep. Perfect. I intentionally did that to show it on the video. Oh. So you see, your side, when you pull it- that's perfect, you evert it nicely, and now you sew through it. The opposite side, instead of grabbing the epidermis, try to evert it as you were trying to do. Grab the dermis? Grab deep dermal and pull it out, and you can grab it underneath this. So grab it here and pull it. So this was the arteriovenous fistula creation- radiocephalic, the radial artery to the cephalic vein at the wrist. The case went smoothly, nothing unusual. The artery was a bit on the smaller size, relatively speaking, but it was still had good flow, and it had nice thrill at the end. The vein was a reasonable size, and dilating it gave us a little extra diameter that was- that improved the flow. The length of the vein was also adequate, we got a nice length on it, so… It went smoothly, nothing unusual, standard arteriovenous fistula.