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Arteriovenous Fistula Creation

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

Transcriptions

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 a 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 ensuring hemostasis. 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. We’re going to make an incision curvilinear to extend it if we need that 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. Can go down to 25 on the Bovie please. Straight. J please. So I don’t know if you can see the vein - it’s over here. Take an ohms retractor 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. Nice. Mobilize a little further distal on top of the vein = superficial to the vein. Turn your tips away from the vein so it's safer. Maybe easier for you if you retract the vein with this, and then use your scissors - so they'll be you countertraction. This looks good enough. Alright, let me just get there soon - over there - later right here - quick buzz.

Let me just retract this and if you can retract… So getting 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. 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 have to superficialize it? Very rarely in the forearm. In the upper arm, patients with the 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. This look pretty good. Alright. So the artery, we felt it right here.

Let's go deep into the tissue here. If you hold this up - just go straight down. This is where you go, you kinda longitudinal. Curvilinear for the cephalic and longitudinal for the radial. Well, essentially, for the subcutaneous tissue, you’re going longitudinal for both along the vessel. This way, it’s less likely that you’re injuring structures in there. It's more comfortable when the patient is under local anesthesia. You can divide this a little more. The artery is over here. I'm feeling it underneath this. Yep, here it is. So if you grabbed this. See the artery. 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 - careful - we don't need to mobilize as much of a distance but - hold on to this - good distance will make it easier to clamp it. Another vessel loop please. See this artery is relatively smallish in size. That's not good. 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 so - tie that off? Yeah. There's a small branch - why don’t we tie it off. Take a 3-0 tie please - oh, 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 coming. Scissors. Okay bring the knot down. Don't retract the vessel too much when you’re tying.

So you still got two 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 that will do. And I use these two occluded and retract it. This way you have minimal trauma to the artery when you're doing this. Okay. You want me to hold it for you? 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 forcep 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 we don’t need to. Doesn't look like it's done. So this is what you want to make sure it's 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. And we see how dilating it makes it really have a good size. So this is the artery. So I retract the artery. So I usually use these towels but can use this. Actually, let’s retract it over to your side is better. 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 ohms 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? Take another forcep - curved one is fine - the right angle one. So we going to make an arteriotomy over here and then anastomosize these two together. Take the beaver blade - white towels actually first. So you see the length of this. Once you see the flash of blood that means you're in the lumen. Knife down. We’ll take the iris scissors next. 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. I’ll take a sponge 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. 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 you see where it's coming from. And either way, when you retract one end, you're putting traction on both in a way. So 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 - no pass it 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. Take a shod please. So I’ll shod these two together. Take a second stitch. So you can take it outside in the two. 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. So you noticed on my side I did inside out than inside out with the other needle, but if you go outside and in one side you can do inside out on the other.

So you see this is a small artery. Be careful on 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 two so you get it all the way down. Shod this then we going to sew with this. So you 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. Just straightforward vascular anastomosis.

First corner stitch especially if you’re not at the - the corner, you do it in two 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 it one of your jaws like that and then going to try that. I can do it from here for you if you want. It's maybe easier. 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. 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. I just - make sure to - make sure that we’re not too long. You're good.

Can you see what I'm doing? I'm pushing the wall of the vein into the lumen so my forcep 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 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. Start with the vein with the the corner stitch first. Take this one underneath? 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. So if you grab the vein open. That’s good. And this is nice and wide - it's good. Now if I tie this. Tie yours to it. Hold on a second.

So if you grab the vein under tension - just a minimum. 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'll be sewing both side 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 tied 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 corner and you're not tying it down, make sure when you're tied at the end you don't tie it too tight because you could pressure it and minimize the flow in the vein. 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 I don't want to loosen it. You don’t want it too tight and 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. Sorry. You want the jewelers? Yes - got them right here - just at the corner, I don't mind using the corner - 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.

So first you open the vein, and 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 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 straightened out. Maybe we can take out this band to minimize the angulation there. 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 this. The longer the distance of the vein with single outflow - without branching - the better the fistula will be the better - 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. 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. I use vicryl with a small needle and just do them about three to four millimeters apart - inverted, deep dermals. You have the 4-0 pop offs and adsons with teeth? You do like a histico closure or - 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 - leaving a little bit of a separation in between the sutures. Still, look at the skin that comes together nicely. At least if it bleeds tonight, it won’t compress and clot the fistula - that’s the point. 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. See how I separate them? So if there’s a hematoma, I’ll escape through. These I pop off. Needle down. You just do the same thing from your end. Sure - I'll take another stitch. And now we feel the thrill very nicely over here.

So the deep dermal inverted - you start in the Sub-Q essentially, get some of the deep dermis and pull the epidermis apart and then cross over superficial and come deep. And it's important to avoid the vein when you're sewing this. That would be a problem. Attending would be frustrated. Take a 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 - 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. Perfect. I intentionally did that to show it on the video.

So you see the 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 and try to evert it as you were trying to do, grab deep dermal and pull it out and you can grab it underneath this - so grab it here and pull it. Here - let me show you. So if you - if I'm - if you're almost, you want to do this. See how it's easy to do. You can see it better - it’s everted better - yes.

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 to 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 went smoothly - nothing unusual - standard arteriovenous fistula.