Transcription
Hello everybody. Today we are going to talk about some of the complications, mainly the procedure complications. I labeled it as a complication in the CAD lab, but since it is a procedure where we are accessing the either the arteries or the veins, so they it can happen with anybody who is doing a procedure, either is in ICU, in the emergency room. So while if you are putting a central line or arterial line, a line, triple lumen, but I will mainly focus on in the cath lab where we do the left heart catheterization, number one, and number two is the right heart catheterization.
So basically, what we are doing in these procedures is putting IV lines into either the veins or the arteries. In a cath lab, you will see that they will have these different catheters and sheaths, which they measure with the what we call like a French. I'll just circle this; they will say six French, four French, 10 French, 18 French. So what does that mean? Basically, if you want to get an idea, the each French divided by PI, which is 3.14, equals millimeter. So basically, if you have a 6 French catheter, I just rounded off from 3.14 to simply 3, so it's gonna be a 2 millimeter catheter. So when we do TAVR in the hybrid room and and for the structural, we usually put bigger sheaths; they can be up to 14 to 18 French. So let's say, for example, if it's a 14 French sheath and you divide it by 3, so you get somewhere 4.6 millimeter of a catheter. So this kind of give you a rough idea of how big of a catheter that we are going to be putting in the arteries and the veins. And the bigger the catheter, the more chances of complication.
So with that, we come to this picture 1, or picture I, little picture A, where you are accessing the femoral artery for the left heart catheterization. Picture B is left heart catheterization through the radial artery. So for the most part in the cath lab, about 90 to 95 percent of the cases that we do are radial access, and as you all know, it is more safer, it's easy on the patient, less chances of bleeding and complication, but they're still there. A number of patients where you have to go through the femoral access to complete the procedure.
So let's start with figure A. So I have here, and that this arrow is your femoral head in relation to the femoral artery. This is your common femoral artery; I'll just mark this, and this is where you want to get the access into the common femoral artery. The reason for that is it is an artery just that just lies on top of the femoral head, so that if you have to press to achieve hemostasis, you can do that, and number two, it is big enough to kind of accommodate a bigger sheath. So when we are trying to get access for into the into the common femoral artery, we use a fluoro; we can put like a hemostat here, we fluoro it, and basically what we are looking at is this femoral head, and what you want to do is to access the femoral artery in the middle of the femoral head, and that's gonna be your perfect stick. And as I said, for the obvious reason, if once you are done with a procedure, you can press the artery against this femoral head to achieve the hemostasis.
So there are two things that can happen; it can be an up, what we call like a high stick, or it can be a low stick. So it can be a high stick, and number two is your low stick, and both of them are a problem, and I get I'll get to it why it is so. Let's come back to the fig picture A or a figure A. Here I want you to look at this what we call like an epigastric artery. So this is your epigastric artery. So if you stick the common femoral artery above the epigastric artery, this is called a high stick, and it can be a problem, and this is because the common femoral artery is a retroperitoneal structure here. So if you access the artery right here, and once you are done with the procedure, you take out the sheath and you try to achieve hemostasis, if you put pressure here, you don't have any bony structure to kind of collapse the artery, so it's going to keep losing blood, and a potential life-threatening situation or a complication that we label as our RP bleed or the retroperitoneal bleed. It is very important to to diagnose this and to suspect for it, especially if you have a somebody who had a difficult access. So it's very important when you are in the cardiac catheterization lab that you know we give a sign out, okay, was it a difficult access? How was the access? It was high or low, because that can help and to pay and the people who are taking care of the patient upstairs in the CV ICU or wherever the patient is going. What happens with the RP bleed is there is slow bleeding into the RP or retroperitoneal space; you might it might not be obvious as as somebody who has a hematoma, so it is, as I said, is invisible bleed, but you cannot see that, and by the time you realize or you suspected or the patient start having symptoms, and the symptoms will be back pain, or they will become hypotensive, tachycardic, and potentially go into shock. So it's very important to kind of you know suspect this, diagnose it earlier before the patient goes into that full-blown, as I said, and becomes an image shock, requiring transfusion and things like that. And the easiest way you can do that is sending the patient to for the CAT scan, and if the patient has a CT scan that shows an active using of the blood, then you know you might ask the interventional colleagues to kind of deal with it, or the CT or the surgeons to kind of repair that, but it, as I said again, it is very very important to kind of recognize this earlier.
Some of the other complications that can happen in the femoral arterial access is if you have a low stick. So there are two arteries; the common femoral artery divides into SFA's, superficial femoral artery, and another artery is the profunda femoral artery. So the profunda femoris is called the left main of the leg; we don't usually hear about it, but it's a very important artery; it goes and supplies the femoral head, all the structures around the hip bone. So that's why, as you have the left main in the heart, the profunda femoral artery is known as the left main for the leg. So if you have a low stick, what can happen is most commonly we see what we call like a pseudoaneurysm. In a pseudoaneurysm, there is a puncture artery, and the blood is just contained with this small adventitia layer, and it can potentially rupture and and and there can be a big hematoma. If it is a small pseudoaneurysm, you know it can be easily taken care of just with the compressing with an ultrasound or the the vascular surgery or the interventional colleague can inject what we call like a thrombin into the neck of that pseudoaneurysm. Another complication is basically if you have a low stick, and then if the patient end up getting a closing device, and some of the closing devices that we use are called an Angio-Seal. The Angio-Seal has a footplate that goes inside the arteries lumen, and it is dissolved dissolvable over the period of weeks, but if you imagine if you put a small in a small artery like in a superficial femoral artery, you put that footplate, it can totally obstruct the artery, or it can clip the other artery or another profunda, and same goes true with the profunda access as well. And of of course, as I said, you have these; if you see this here, the bifurcation is below the femoral head; obviously, again, if you have to achieve hemostasis and you're pressing it manually, you might not able to achieve hemostasis since there is no bony structure behind that. Another potential complication that can happen is if you put the needle and that goes through the vein, the femoral vein, which is medial to the artery, and then into the artery, and once by the time you are done with a procedure, the patient comes back, you start to hear the bruit and the thrill and maybe an hematoma, so that could be another potential complication, what we call like an arteriovenous fistula. Arrest you all know it can be bleeding, it can be infection, and and some other things, a nerve injury. I won't go into detail; I'm just going to stick to the pertinent that you need to know.
Let's come to the picture B here, the radial cath that we do; they are two arteries that you can access; either it's a radial artery or the ulnar artery. You might not see us accessing the ulnar artery that frequently, and the reason for that is it is a deeper structure, and it's hard to kind of put a TR pen or compressing compressing device on it to achieve hemostasis. So basically, most of the time we do radial, and of course, if you have somebody who goes radial is not good, you will not to go to the other because he can potentially jeopardize the circulation of the hand. And the reason we do the radial is we know even if the radial artery is from both, you have this superficial palmar arch and you have a deeper deep palmar arch, which kind of shunts the blood in both direction, so even if you have a thrombosis of the radial artery, most of the time it's not a clinic you know of clinical significance. And to give you an example, most of the surgeons, that's cardiothoracic surgeons, they sometimes use the radial artery to kind of use as a conduit for the bypass surgeries. Another potential complication that can happen in the radial artery is what we call, and is very important to kind of recognize this, is the compartment syndrome. If there is a bleeding, big bleeding into the to the forearm, is it it is a very you know compact space wrapped around with the fascia, you can have compartment syndrome, and it is very important to recognize that.
With that, we come to picture of the procedure two, which is right heart catheterization. Ultrasound-guided is the basic and required technique; we we don't do anymore of the blind sticks; ultrasound guidance is the is the way to go. Basically, you want to make sure that you are going into the vein, not into the artery, sorry, you know basically you are trying to make sure that you don't go into the artery and you are going into the vein by compressing it, and then more preferably using a micropuncture, you should use a micropuncture needle, then you put a wire in, and when you put the wire in, I've just draw it here, you need to see how far the wire goes. If the wire goes straight, then you are in the vein, but if you put a wire in and it kind of goes along like this, like as if the arch of the of the the aorta, or it goes like this and just curls here in the top portion of the chest, that means that you're hitting the aortic valve. So it's very important when you put the wire in the micropuncture to put it kind of way; you can even let it go all the way to the IVC just to be sure that okay you are in the venous system. A complication that can happen in these patients, obviously, as I said, you can have bleeding, you can have hematoma, which can be potentially devastating because of its close proximity to the Airways; the airway can get compromised. Another complication that I want you all to kind of understand is in this case also what we call is a low stick; we usually don't talk about it, but it is very important. If you are accessing the vein, try to access it in the middle of the neck, so you want to make sure that you are in the middle of the neck, because if you have a low stick in patients who are obese and have a short neck, you have this pleura here, so going down here, and if your needle is directed down, sometimes what you can do is what we call like a pneumothorax or hemothorax; that is something that you have to kind of keep in mind when you're doing this procedure, but I think for the most part when we do ultrasound, it is a safe procedure. Thank you very much.