Pediatric Vascular Access in Brief: Preoperative, Operative, and Postoperative Considerations

In the United States, there's an estimated 5 million central Venus catheter lines placed. And several of those are in the pediatric surgical patient, which is why today, we're going to break down the basics. Here at Cincinnati, we deal with a bulk of some of the complex uh vascular access as well as all the um catheter based access for dialysis. That's Dr. Alex Bondock. He's a pediatric transplant surgeon at Cincinnati Children's Hospital Medical Center. He's going to walk us through really everything that you need to know about pediatric vascular access. So, don't go anywhere. This is the stay current podcast. Before we get too far, let's review the types of central access. The first is central Venus catheter. These are not tunnelled, they're typically for temporary use in the hospital. They can have one to three lumens. We'll get more into the indications later. Next, there's a port, which is for long-term access on the order of months to years. The catheter is tunneled and there is a totally implantable reservoir for access. They're often used for things like chemotherapy and they can have one or two lumens. The broviac catheter is a tunnel line with a cuff and it can be used for months to years for things like chemotherapy, parental nutrition, frequent blood transfusions. They can have one or two lumens. Finally, hemodialysis or feresis catheters can be temporary if uncuffed or permanent if cuffed. They're for uses as their named, hemodialysis or feresis. The catheters can have one to three lumens. With so many patients necessitating central access, it's important to keep in mind some guiding principles. For example, where do we place central access? From a purely logistical standpoint, um chest and neck central Venus access is preferred. There's a fair amount of evidence to suggest an increase in the rate of complications and infection with femoral access. So that answers the question of where to put a line, but how about why? Well, the list of indica it can be extensive including a need for total printal nutrition, resuscitation or hemodialysis and really the list it just goes on and on. As for contraindications. Contraindications. If you have thrombosis, um if you have collateralization, if you have central stenosis of the SVC, then you start having to do more exotic uh concurrent procedures or use the groins or go to a different access point. While some complications can't ever really be avoided, there are definitely some pre-procedural considerations to keep in mind when performing the workup for a patient who just needs IV access. Unless they have some other congenital anomaly, usually a cardiovascular anomaly, I wouldn't say that it's routine that you have to get let's say an ultrasound would be our first screening test. But if there are, you know, this is line number four, five, six for a patient, then you're talking about starting usually what we like to do is a Doppler Venus ultrasound to look at the jugulars. You can sometimes if the child is small enough see the SVC and look at the subclavian. You might escalate that to uh a contrast enhanced axial image either MR or CT venogram to understand and even then, sometimes we're prepared to do venography trans, you know, um on the table with fluoroscopy at the time of the operation. Let's say we finished the workup and we're ready to place the line. What's the first consideration? Starting out from a positioning standpoint is critical. What I would tell you is especially in small children, neonates and infants is that the more versatile way to position the patient is over a vertically oriented shoulder roll. If you put it straight up and down parallel with the spine, you get not only hyper extension of the neck, but you get the weight of the shoulders to drop posteriorly. That will give you access to all four, you know, all the subclavian bilaterally and the jugulars bilaterally. Great. So positioning is critical to making the percutaneous stick easier for the surgeon. But pediatric patients, they come in all shapes and sizes. So what happens when you have a really small neonate? Is there a certain needle we should be using? For really small babies, many surgeons would prefer a cutdown. Dr. Bondock does have a suggestion for a needle you can use if you do place a line percutaneously. I like to use a micropuncture kit. The micropuncture kick comes with a 21 gauge finder needle, which is a lot different than the 18 gauge needle that comes with some tunnel blind kits. Okay, so they're position on the OR table with a vertical shoulder roll. We have our micropuncture needle kit. We're ready to place this line, but first I got to ask, do we want to use ultrasound or external landmarks? Using an ultrasound for an IJ um central line attempt is the number one preferred way of doing things. It's certainly the safest, uh the lowest risk of pneumothorax, the lowest risk of um injuring the artery of the carotid. Got it. So once you see the IJ on ultrasound, where on the neck do you want to puncture? Especially for large bore access like a dialysis catheter is to stick the patient as low as you can on the neck. Usually what I try to do is I take the ultrasound probe. The ultrasound probe is about 12 mm in diameter. So if you just sort of lever it against the clavicle, you have a pretty reasonable spot where you can um follow your needle in and you're sticking them pretty low. Wait, why so low? Why not in the mid portion of the neck? That leaves more of a catheter to curve in the neck. And so that's where I in my opinion you run into problems with patients if they when if and when they turn their neck or the more lax amount of catheter in the neck. I've seen catheter spit out of the of the SVC. It's strange, but I've seen it a couple of times. Let's say we've lost both IJ access sites or the patient is in a cervical collar, but the patient still needs central Venus access right now. Then we should consider a subclavian line and that's more of an anatomic placement. At the junction of the medial, the median and the medial aspects of the clavicle, I usually go at least a finger breath or, you know, almost a centimeter inferiorly and lateral. Um, and stick away because if you stick too close to the bone, you're not going to be able to lever under the bone. Um, and so that's the important thing is once you're sticking and you approach the clavicle, you don't want to turn your needle at a, you know, at a harder angle, like a 30 degree angle. What you really want to do is keep your needle flat and push down on the patient's skin. The direction you're pointing the needle in is also super important. I typically aim directly at the sternal notch and then if I can't get it from the sternal notch, then I start angling wider towards the angle of the mandible, moving in sort of a in a radial motion. So typically we want the tip of the catheter to be at the junction between the right atrium and the superior vena cava. Often chest x-ray or fluoroscopy are used in the operating room to make sure that the tip is in the right location. And if you have trouble finding where the catheter tip is located, Dr. Bondock has another tip for you. The what I was taught by our c nurses is that if you think of the trachea as the midline of the patient on an x-ray or on fluoroscopy and you draw that theoretical midline, you continue it from the carina all the way down. And then the right main stem bronchus acts as a hypotenuse of a right triangle. And you connect that theoretical midline to the hypotenuse. If you leave the tip of your catheter in that triangle, in the area of that triangle, that will always be the atrial caval junction. Another common option is to use fluoroscopy for line placement. I would tell you I don't routinely order x-rays if it's a single stick uncomplicated using fluoroscopy. That's based on some data out of Children's Mercy Hospital in Kansas City. Scroll down onto the media player. We're going to give you a link to the article below. Now, if something seems strange, obviously don't hesitate to get a confirmatory post-procedural x-ray to confirm line placement. What are some post-procedural complications we need to keep aware of? pneumothorax, um hemothorax, um injuring the artery, either the subclavian artery or the carotid artery. Um and then sort of very, very exceedingly rare things like chylothorax or thoracic duct injury. And then you have your long-term complications like thrombosis or catheter displacements or kinking. If it's a really, really long time, you got to consider actual degradation of that line. But one long-term complication that you really got to be diligent about is line infection. So how do you approach this patient? Your first clinical decision point is, is the patient septic from this line? If the patient is septic from the line, it's source control, right? The patient's in the ICU and sick, go to the bedside, under light sedation, pull the cuff, get the line out. What if the patient is not septic, but they are line dependent or they have complex vascular access issues? Then we figure out what is growing, um can we treat it? Is it sensitive? And then we do serial blood cultures. And that if you can achieve um uh culture negativity and sustain culture negativity, that line might be salvaged. The decision to remove a line or treat medically has become rather nuanced, especially for some patients with chronic central access needs. Societal guidelines can be found online and often our infectious disease colleagues are consulted for complex cases. You know, locking solutions have been around for a long time, but they are predominantly antibiotic locks. That's Dr. Paul Wales. He's a director of the intestinal rehabilitation program at the Cincinnati Children's Hospital Medical Center. And frankly, the problem with them is that you develop resistance. So that led some providers to utilize ethanol locks. Antimicrobial. It doesn't have any resistance. And it'll kill bacteria that are both planktonic, meaning floating around in the in the lumen, or sessile, meaning that they're embedded in a biofilm along the wall of the catheter. Problem is, the price of the ethanol in these locks skyrocketed. Leading Dr. Wales and his team searching for other solutions. They found one in Canada. And it's called uh Kitelock. And what it is, it's a 4% uh tetrasodium EDTA um uh chemical. What are the benefits of Kitelock? It's antimicrobial, uh there's no resistance to it. It's uh antifibrinolytic and uh antithrombotic. We'll give you links to all Dr. Wales publications on different types of locking solutions and some information about Kitelock. But keep in mind, you can't get this product everywhere. It has been uh licensed in Canada for pediatric use. It's now licensed in Europe and it's licensed in Australia. Let's finish up by talking about some less common scenarios. For example, what if you have a patient where you've exhausted all of our options for femoral, IJ or subclavian cannulation, but they still need central access. Something we consider is a trans lumbar line where um the IR doctors, you know, we work together again where they'll get access and you actually have to tunnel through the the the back musculature into the infrahepatic cava and then send a line up that way. Now a different scenario. The patient is crashing right in front of you and you have to get immediate access. One rarely used technique is just to cut down. My thought was you turn the baby's head to the right, you know, to the baby's left and usually right at the angle of the mandible, you can make a horizontal incision just lateral to sternoid and oftentimes the first big vein that pops up is the facial vein. And you know, you just you you what we do is or what I was taught to do is you bevel the catheter really hard because you don't really have any other way, you know, you're not putting a wire down that. You're just blindly passing the catheter. So if you put the bevel on it theoretically it, you know, it'll follow a path. It won't, you know, it won't bump up against um the vessel if it's cut flush. Thank you Dr. Bondock and Dr. Wales. That is a wrap on vascular access for the pediatric surgical patients. If you like this episode, leave us a comment, leave us a rating, whether you're watching us on YouTube, listening on your favorite podcast player, or the best way to get our content, the stay current pediatric surgery app. It's free on the Apple App Store and the Google Play Store. But until then, I'm Rod from Cincinnati Children's and remember, knowledge should be free.