Dr. Olicker is still with the team for Part 2. The team discusses the decision of transporting a neonate patient to the closest hospital vs. a facility with inhouse neonatal specialty care services as well as complications with the ductus arteriosus as well as the difficult decision of determining a the viability of a neonatal patient's viability for EMS.
Prehospital Paradigm Podcast
Understanding the Neonatal Patients for EMS - Part 2
(upbeat music) - So for neo-no-care, how important is doorway assessments? You are the pediatric assessment triangle. - I'm not familiar with the term pediatric assessment triangle. (laughing) - That answers my question. - What is this pediatric assessment triangle? - It's a doorway assessment that has to do with three aspects of basically just looking visual of the patient and just their appearance as part of it. And that to me is huge doorway appearance. Like is the baby crying? Is it not crying? - So I will tell you there's a lot I can tell you about a baby's condition just by looking. - Sure. - While I don't necessarily have a named tool, although with the exception of heart rate, I guess the app guard score is-- - The app guard. - Is an assessment. - The app guard kind is the one with the pediatric. - But you can tell a lot about a baby's condition by are they breathing? Are they crying? Are they pink? Are they flexed? - So same, same, but different. It's, yeah. - All right, we've talked about the term baby who has everything going for it. May have some primary apnea. May have some things that we have to work through. - You look terrifying. Let's talk about the sad part here. When is a patient not viable? And when is resuscitation futile? - So I will tell you that that's gonna be a really hard thing to determine in the field. The real answer that we're using right now is that we are not resuscitating below 22 weeks. 22 weeks is at the moment, considered the lower limit of viability. There's not really a weight that is considered to be viable or not viable. - And we certainly wouldn't know the weight in a field delivery. - It's generally based on maturity and maturity is a function of mostly gestational age. But that's not gonna be something, unless if you come in and a baby is gelatinous and, - Yeah. - Well, 22 weekers are gonna be gelatinous. This is probably not the part you want in there. (laughs) But if you come in and well, I say there's no lower limit of weight. If a baby is not breathing and you have no equipment that is small enough to help breathe for that baby, that's a baby that we're not going to be able to help. - Yeah, that's fair. - And that happens to us in the delivery room too sometimes and we'll be counseling families with babies who are around that age of period viability and we'll tell them that sometimes a limiting factor here is that we don't have any equipment small enough. But you're not in the field going to be able to tell a 22 weeker from a 24 weeker or a 22 weeker from a 20 weeker or 19 weeker. - Absolutely. - Or a 21 weeker. - Sure. - And at that point, it's, the rules are sort of still the same. So you want to get that baby warm and keep that baby warm. In this case, you're not going to want to dry and stem. What you actually do is wrap them in plastic. And you can use, depending on what you have where you are, you can use saran wrap, you can use, you can put a baby into a Ziploc bag with the head sticking out. We, right now we're using kind of fancy, sophisticated ponchos that have a little head covering and it has Velcro down the center. But before we had the ponchos, we just had plastic bags and we put the baby in the bag. And that's because they have so much surface area and their skin is so permeable that you're going to lose a lot of both their just general blood volume or fluid volume through their skin and they can get cold very quickly. And so you want to keep that baby warm and the way to keep that baby warm is going to be wrapping them in plastic. And so of all of the things we've talked about, the things that you can stock on trucks, if plastic wrap is not something you carry, that can be very useful. You want to put the hat on and we're talking about the same hat. So the same one that might fit you. - Putting on a 19 week or 20 week or yeah. - Or we'll put on a baby. So you get your baby, you put your baby in your bag, you wrap your baby in plastic. And at that point, it's exactly the same. So airway, breathing. When babies are at the edge of viability, these are babies that we often talk to families about. It's not progressing to compressions if we can't get a heart rate above 100 with just airway and breathing. And that's because as we talked about before, the issue is generally not the heart. The issue for periviability is always going to be maturity of your lungs. - Lungs, right. - And if your lungs are not mature enough to exchange gas, then no amount of compressions is going to - Is going to help. - is going to get oxygen throughout your body. - Now I think for some of the listeners hearing this, they're gonna revert back to what we were just saying a minute ago that as long as the placenta's doing what it's supposed to be doing, why cut and clamp the babies getting oxygenation through the placenta? Why can't we leave that baby attached still then and not cut it and transport? At what time does that circulation stop? - I mean, circulation stops when your placenta separates and I don't think you have a good, you don't know when your placenta has separated. And even when you're at that point, you do want to establish airway and breathing. But even in these smallest of babies, we still do delayed cord clamping. And it can actually be most important for these smallest of babies to get that little bit of extra blood volume on their way out. - I guess less so we don't have that confusion. What do we mean by delayed? We mean, obviously not immediately, but two minutes, five minutes, 12 minutes. - We use 30 seconds for the small cities. - There we go. (laughing) - You don't, you don't, especially in bigger babies, you don't need to use that 30 second cut off and you're right, there are bigger babies who, I mean, if you want to go extreme with it, there are some families who choose to not cut the cords at all. And your vigorous healthy term baby, if a family wants to stay connected, that's okay. In a baby who needs resuscitation, we, for the tiny ones, we use 30 seconds. - That's good to kind of put up. - If babies are doing well, for the tiny ones, they're just about always going to need resuscitation. Below 32 weeks, even if babies are crying, we put all of those babies on CPAP. And you'd be surprised that 24-weeker will often come out crying. - Wow. - We can often resuscitate even your smallest of babies with just CPAP or just a few breaths and then CPAP. - That's so cool, that is cool. - CPAP, right, it's not an invasive-- - We should do a bit on that. - Are you giving a lot of surfactant? - Not in the field. - No, no, no, no, all you. - Personally? - Well, Nick, you are-- - Yes. - Yeah. - We do give a lot of surfactant. So, for people who aren't as familiar with it, surfactant is a detergent lung substance in your lungs. Your lungs make it throughout your life. It is, there are two types of primary lung cells. The type one cells kind of surround those sacs that hold air and the type two is the one that produces surfactant. So surfactant is this kind of slippery detergent like material and it's job is to break the surface tension of water. And so, if you think about a pool and doing a belly flop, think about how much it hurts with just trying to break the surface tension of that water. So then if you were to just drop a little bit of soap on there and think about that breaking apart more easily, that's what you're hoping for for opening up the lung. And so it overall increases lung compliance, which makes it easier to ventilate and easier to oxygenate and to do so with much lower pressures. A baby starts to produce an adequate amount of surfactant to support its needs somewhere between 32 and 34 weeks to a stationary age. And so, under that, it's very common to need surfactant. Over that, it's less common, but some babies still needs surfactant. - I wanna go back to ages and deliveries and more transportation. So it's funny you say 22, 'cause I know that. Obies cut off for taking a patient's 20 weeks. So we have taught, and it's in our protocol, at least locally, that 20 weeks is the cut off. So if you're 19 weeks, we go to the local emergency department, they will see you and assess you. If the patient's 20 weeks, we say you need to go to a ER, that's OB capable, that has OB services there, 'cause right now, I don't have OB services at my hospital. So it's interesting to me that OB will take them at 20 weeks, but you're, say, viability is 22 weeks. So I think that making it easy for our listeners, at least in our med control, is that if it's 20, or if it's below 20, so 19 weeks below, any ER is appropriate, 20 and above should go to a facility that has OB services, or if, let's say they have a history of premature deliveries, or this is a highly complicated pregnancy, if they have the ability to go to a place that has NICAs available services, that should be the destination. And picking those destinations is important, and maybe if it's gonna add five more minutes to your trip, the local ER is 20 minutes away, but my NICU center is 25 minutes away, in that pre-me of 20 to 38 weeks, that you should go to a NICU center. - With the caveat that if you are sure that you're going to be able to get to that place with a NICU center, so you're much more likely to have a better outcome delivered inborn than you are delivered outborn. And if you're going to have a pre-me or a complicated delivery, you'd rather have it in an ill-equipped ED than in your truck. - I've got a lot more services in my ER than just the guy driving and the one in the back. - Mm-hmm. - Yeah. - You're the guy in the back. The, you get to deliver-- - There's a problem. (laughing) - Like I was saying earlier off, I've delivered one in the field and it was an attack scene, it was just, I'll never want to do it again. - All mine, which is only three, I just was essentially there to bear witness. I mean, it was, let's take a, okay, it's coming out. And you know, it was, I was just, I was just there cleaning up the mess. I wasn't really there to actually, I've done nothing to manipulate, help a child out ever. It's, they've all just come out on the cot. That was my time in East Cleveland and it was just like, oh, the kid's out, okay, cool. There we go. Now let's do the things I know. - And sometimes you can bring your NICU services to where you need them to be. - Also true. - So if somebody rolls into, we were talking about earlier, if somebody rolls into a freestanding ED that isn't associated with an OB service or a delivery service or a pediatric service. If you need to, you can get on the phone and you can get both OB services and in the particular case I was talking about, you got a NICU fellow too. And we were able to get together a team to safely deliver these were 32 week twins but to safely deliver by C-section 32 week twins in the OR of a freestanding ED with no delivery service. - Wow. - So, it's-- - That's terrible. - Right. - It was-- - That's a day. - Exciting. - Yeah. - But I mean, use the resources you have and sometimes the resources aren't where you are but they can be brought in. - Correct. - And the scheduling of NICUs is actually backwards from what we're accustomed to with trauma, right? - So, we're always go to trauma one or trauma two and then this is actually-- - It's the opposite. - Yeah, so a level one NICU is, or level one's not a NICU, a level one nursery is going to be your normal newborn service. - Got it. - Level two is-- - Two brings you what services? - So two, two, you have a special care nursery. These are places that can take up to, or no younger than 32 weeks or can keep no younger than 32 weeks. They can deliver CPAP. They can certainly do things like fluids and antibiotics and blood sugar management and that kind of stuff. Once by the textbooks, they can, (laughs) by the textbooks, they can keep ventilated patients up to 24 hours as long as they are improving. That's going to be very dependent on-- - Seems subjective, but okay. - It'll be very dependent on your level two NICU. None of the level twos in the area that we're in actually have that capability right now as far as I know. This is all a point of controversy that you may want to take out too. (laughs) - Well, we don't have to spend any time on it, just the fact that it's backwards that the higher universe better in your world or the better than-- - Right, so not better, but more equipped. - More equipped. - So a level one's going to be your normal nursery. A level two can take as young as 32 weeks by the books and they can do respiratory support up to CPAP and we're not in base of ventilation and they can do your fluids in your antibiotic management and things like that. Once you're past that, you're looking at your level three and these are the places that are going to have your surgical services and are going to be able to manage invasive ventilation. And level fours are going to be the places where three Bs and fours are sort of different names for the same services. So there used to be three A and three B and now I think we mostly talk about three and four, but your level fours are going to be the places where you're doing things like ECMO and preparing babies for cardiac surgery. - Yeah, all of the cutting edge stuff, got it. - Okay, where are those centers throughout Merphist, Ohio? - Level fours. - Well, I guess Akron's probably going to be-- - So Akron Children is a level four. They have a network of delivery hospitals that have level threes. So Akron takes deliveries, I know from Summa, from Akron General, yeah, Summa Akron General and those are their two main ones that go to Akron Children's. And those are both technically level threes. Everything at Akron Children's is an outborn unit and so they don't actually have a delivery service there. They get all of their babies from their delivery services. So their delivery services have the level threes. The level four is at their children's hospital. I come from UH. Rainbow is our level four, so downtown. We have just started, we've just opened two level twos. So we have southwest on the west side and we have a Hoosian on the east side and pretty soon tri-point is also going to be opening as a level two. - Hooper. - And then we have a fairly extensive network of level ones or normal labor on our service. - Sure. - The clinic has its surgical services and its ECMA services, downtown at its main location. - Thank you, that's right. And then it has an east side and a west side delivering hospital and those also operate as level threes. So they have Fairview on the west side and Hillcrest on the east side. Metro just moved its level four, so it had the level four and I think they're pretty proud of this but they moved from their older big-based hospital to now a level four still serving the same area but they have single bed units the same way that we do at Rainbow which is nice for the families there. - Yeah. - So yeah, those are gonna be our main level fours in the northeast Ohio area. Rainbow Cleveland Clinic main campus at Metro. Akron is south of us but their main level four is gonna be Akron Children's with its two level threes. And then when you're moving to other areas, nationwide has a level four with-- - Columbus. - Yeah, nationwide Columbus has a level four with a large network of level twos and threes. I know since Nanny has its main level four and I know it has a big network of level twos, I'm not actually sure about level threes but every place you go is gonna have slightly different strategies for how they serve their community and how they serve their encachment area. And so, and they're really doing what they think is going to be best to serve their patient population depending where they are. So places have found that it is helpful to the community to have delivering services close to home. And as we said before, the majority of deliveries go well. The majority of deliveries are normal pregnancies with normal newborns that never need anything more than normal newborn care. And so for those families, having your newborn care close to home is really important for a more specialized care just because of the nature of it and the needs for equipment and the needs for people and the needs for 24/7 very acute care. It has to be more centralized. - Yeah, of course. So just kind of getting back to, we touched on this a little bit. We've clearly focused on the airway, the breathing, ventilation, oxygenation of the kid. Let's talk about some monitoring tools and what is and isn't different. We certainly talked about pulse oximetry a little bit. So let's get back to that 'cause there's some nuanced stuff with pulse oximetry in the newborn. And then also, let's talk about capnography. You said you just did a piece on capnography and without getting into the nitty gritty of cap now, I guess let's just start with that. Does anything change from what I'm used to if I'm putting capnography? So if I put an advanced airway in this baby, are my waveforms any different? Are my values any different? Am I looking for the same things? Are there other nuanced things I need to know about it with capnography? - The biggest thing to know with newborns and capnography, especially in the field when you're moving or not in the field in the truck when you're moving, is going to be, your number is not going to be as reliable as just having a waveform. So what you're using for capnography isn't really going to be an assessment of whether or not you are achieving ventilation to the CO2 that you are targeting. What you're really trying to see with your capnography is just my airway is in good position. - It's a good placement. - If I don't have a waveform, my airway is not in good position. And if I do have a waveform, my airway is in good position. There's, I've heard a misconception that if you have an esophageal intubation, you'll still get a waveform. You won't. - I agree. - You. (laughs) - We'll see you a slope. - Yeah, exactly. So, especially, especially in the-- - I hope that's not a misconception. - I don't. (laughs) - That shouldn't be a thing. - When you have been delivering bag max ventilation, sometimes you have actually bagged CO2 down into the stomach. And so, in esophageal intubation, you might see CO2 initially. - Value, right. - Yeah, you might see it initially, but no waveform, and it'll go away. - Right. Yeah. - And it'll come back. - And not come back. But as long as you have a waveform, you have a tube that is doing its job. Beyond that, because of the small title volumes of babies and limitations of the equipment, it's hard to get a reliable reading necessarily. - So, what you're really looking for is a waveform. - It's just waveform. Oh, that's great. - That's good to know, though. - That's great information. Because we-- - Well, when you're talking about this is your title volume. - That's your title volume. - That's probably the sampling. - That's the sample size of-- - That's probably the sample size. - Of a side stream, yeah. - Yeah, so. - Yeah, absolutely. No, that's a great point to the, because we spend, at least in this area, I don't want to speak to the rest of the view. In the viewing area, but certainly in this area, I think we focus a fair amount on the value itself and it's impact on what that means to metabolism, perfusion, ventilation. - This is another point where babies are a very different group than older kids and adults, and especially pre-term babies. Babies are remarkably resilient with derangements in their blood gas. And so babies can be remarkably resilient when they're retaining CO2, and while you will look at an adult with a CO2 of 55, and be very concerned, I will have a respiratory therapist hand me a blood gas with a CO2 of 55 and say, "Great, we're in target." - Meh, meh, meh. - Yeah, exactly. Meh. (laughing) - And the reason is we work in a world of permissive hypercapnia and for a couple of reasons. So one of the things that we're really trying to avoid with mechanical ventilation is going to be trauma, so trauma to the lungs, so barotrama and volutrama and even an elective trauma. And so the less pressure we can give, the less trauma that we are causing to those lungs. But also having rapidly decreasing CO2 is not going to be good for perfusion, especially brain perfusion either. And so babies are remarkably resilient with CO2s that are a little bit higher, and some of these older babies, not ones that you're going to see straight after delivery, but in some of our chronic babies, if you get, because they've seen higher CO2s for so long, and you probably don't even want to know what some of these higher CO2s babies have seen for months are, but like triple digits. - Sometimes. - Really? - Wow, that's nice. (both laughing) - I've had babies who have triple digit CO2s for at least a week at a time. - Ooh. - Wow. (both laughing) - It's not a sign of health. (both laughing) - Understood, but still, it's still, wow. - But when you, sometimes when you have babies who are riding CO2s that are higher in the 60, 70 range for a long time, you get their CO2s into the 30s or 40s, and their brain doesn't tell them to breathe anymore. - Look, I mean, that scans, I mean. - Yeah. - Even for the adult population, right? - So I'll tell you that 55 doesn't, it doesn't really bother me, I see for the adult time. - Over 100 I get concerned, for the, I guess, for my education, are they compensated? - Yes. - Um, the, the, this is, I mean, stating the definition, which is gonna sound silly, but the more chronic ones are gonna be compensated. - Sure. - And so when you have a newborn with a CO2 over 100, that is a very sick infant. When you have a more chronic, so once the-- - They've been there for a month, and their CO2 is 80, but their pH is normal. - It's usually longer than a month, but when you have, especially these kind of, these babies who started off in that periviable range, you have very immature lungs. They go on to develop significant lung disease just from the amount of ventilation that is required in order to help them exchange gas. And as these babies get older, again, not a sign of health, but you'll see blood gases that are like-- - They're just hypercarbic. - 735-108 with a blood carb of 55. - Oh, so there are chronic sea openers that have been living there. - I mean, I have a chronic super years at 70s, 80s. - Sure. - They're normal. - They live in there, right? - They live there, right. - They're bicarb 40/50s. So, if I saw it in a kiddo, sure. - Yeah, we would. - If it's compensated, I'd feel better, but I'm still like, I shouldn't see that in a kid. But you're telling me there's kids like that, so. - There are. They are chronically ventilated. - Not thriving, but living. - They are chronically ventilated. These are babies who often go on to go home with tricks and vents. - Tricks and vents, yeah. - Well, it also tells me that I get a lot of haddies, kids. So I will probably-- I haven't seen one blood gas that bad here from haddies, but I will now. - Now you're on the lookout. - Now you're on the lookout. - And now you're on the lookout. - I mean, I would hope that's an inpatient blood gas. - Yeah, I think that if they're at long-- these long-term facilities, though, these kiddos, they're obviously chronically sick. And I think that they do a good job of trying to keep them in that facility. And they're a little slower to push them out into the hospital system, because I think they try to manage them maybe a day longer than what they should until they're really, truly sick. - That's a thing. - They now need to go back into the acute hospital system and out of the long-term care. So that's been my experience with the long-term kiddos. - Yeah. - All right, pulse oximeter. We talked about campnography and somehow spiraled that into-- - Spiraled into bad blood gases. - And into some gases, pulse ox. There was a couple of things we talked about off air that I said we definitely need to, and that was the pre-post ductal thing and normal sats for a newborn. - For a brand new barn. - For, yeah. - So-- - So the entry-- - What are the high points there? - High points. So a baby's going to come out with a sound of about 65, which is about what the entry to your environment is. That's why your baby's going to be blue. You have 10 minutes to get to a sound of 90. Another, I mean, I guess this is a little bit of a tangent, but another important change in NRP over the last decade or so has been, there was a time when all babies were resuscitated with 100% oxygen. And then we moved on to resuscitating preemies, I think with 100% oxygen, but doing less in term infants. And we have found over the years that more oxygen is not better. In fact, the less you can use, the better. - Better, okay. - And especially in preemies, hyperoxia can sometimes be just as bad as hypoxia. And so we, NRP is pretty specific for term newborns. So we always start resuscitation of the term newborn at 21% and go from there. Certainly if you were starting compressions, you should have escalated from there to 100%. - But, I mean, I was gonna ask, at what point do we start cranking that up? But that's a great. - So you start cranking that up, and I brought you those little cards, but you can see it on there. But if you're looking at NRP, it actually tells you what your stat should be at what point in time. And if your stat's not where it should be at that point in time, then you start cranking it up. - Our protocol has the same table. - Then you start cranking it up. And you're not cranking from zero to 100, but maybe you're cranking from your number zero. But you're not cranking from 21 to 100, but you're maybe cranking from 21 to 30, or 21 to 40, and seeing where you got. And so, yeah, there's your nice little table. - I think that's a good point to make, because we might be doing everything right, but it's retreating the patient, not our machines. And we need to sit back and realize that there is a difference here, that we are switching states of oxygenation, and that it's gonna take a while to get them up to where our normal is. - Yeah, so if your baby is three minutes old and their stat is 72, that's actually fine. There's no need to escalate from there. And so, that's-- - That's gonna be a high stress, low frequency thing for us, though, so for somebody who's used to all the time treating patients and making their sats, at least 96 and above, it's hard for us to see somebody in the 60s, 70s, and not act, but we need to calm down, relax, know our clientele, and take that breath and pull out sorta dose. - Well, we haven't gotten to drugs yet. - No, I would say, if they're breathing and they're breathing vigorously and fast, 40 plus times a minute, I think they're good. - And they're pinking out. - And they're pinking out. - Yeah, this is great. - I mean, for a term, newborn, if they are breathing and pinking up, these are babies who may never see a pulse ox at all. And as we said, most newborns are healthy, and most newborns never see a pulse ox at all. But for a baby who does require resuscitation, (indistinct) (laughing) - You're, where you want to monitor the pulse ox is also gonna be important. So in adults, when you think of the ductus arteriosus, you only think of it in terms of the patent ductus arteriosus, and you think of it as being pathologic. All babies are going to be born with a patent ductus arteriosus. It's part of fetal circulation. - Required. - Yep. So the other part of fetal circulation is that blood is shunted away from those collapsed lungs. They're not exchanging gas in utero. And so the lungs are collapsed down. The blood vessels are going to be small too, and babies are born in a state of high pulmonary vascular resistance. And that is to shunt blood away from the lungs when they're not using them. So the lungs get just enough blood to grow during fetal circulation. But otherwise the blood is shunted back into systemic circulation. So babies are going to be born with high respiratory, or high pulmonary vascular resistance, and as they start to breathe, those lungs are gonna open up and the pulmonary vascular resistance is going to drop. So when you have high pulmonary vascular resistance, you're gonna have less oxygen exchange or less oxygen and delivery, which means, and as early on, so initially, the pulmonary vascular resistance is going to be higher than your systemic vascular resistance. And that's what it's supposed to be, right? So you shunt your blood across that ductus into systemic circulation. As your pulmonary vascular resistance drops, it becomes lower than your systemic vascular resistance. First, it'll be bidirectional, and then it'll be all left to right. So when you have blood shunting across your ductus arteriosus, everything before that, so everything that is coming from your lungs is going to be oxygenated, right? So blood that is returning from your lungs and going out the left side of your heart into systemic circulation is going to be fully oxygenated. Blood that has gone to your lungs, but the pulmonary vascular resistance is just too high and can't get in, is going to shunt back right to left across that ductus, and it's going to mix with that oxygenated blood and cause overall less oxygenated blood. So a better measure or a necessary measure of if you are exchanging oxygen is going to be, what is your pre-ductal set? What is the saturation of the blood that is being delivered to my lungs and then coming back-- - Back across. - Yeah, going back from the lungs, back into the systemic circulation, the way it's supposed to. So from the lungs, since the pulmonary veins back to the left atrium, not making it to the lungs across the ductus arteriosus, back into the aorta. Does that make sense? - It does. - For anybody that's seen an anatomy book, but-- - I was going to say this is something that often-- - This takes me back to the first year of med school. - This is something that often requires pictures. - Yes. (laughing) - No, no, explain it, wolf, in post, we'll throw some pictures in there. - Yep. - Okay. So the way postnatal circulation works is if you start at the left ventricle, you have blood that is pumped from the systemic side of your heart, so from your left ventricle, out through aorta to your body, it goes to the capillary beds, comes back through your veins, through the vena cava into your right atrium, goes from the right atrium to the right ventricle into the pulmonary arteries, goes to the branch pulmonary artery to the lungs to get oxygenated, and from the lungs is going to go into the pulmonary veins back to your left atrium. So it's all a nice series. In fetal circulation, you have high pulmonary vascular resistance, and that is because you're not using those lungs to exchange gas, you're just getting them enough blood to grow. So blood, as it's supposed to, during fetal circulation, is going to go through your pulmonary arteries, but the resistance is going to be higher, and so some of that blood is going to go to your lungs, a little bit of that blood is going to go to your lungs, but the majority is going to cross the ductus arteriosus from the pulmonary artery back into the stomach circulation. So from the pulmonary artery into the aorta, all babies are born with this ductus arteriosus open. It's supposed to close your taut in med school that you take your first breath, everything slams shut. That's not actually really how it works. - That doesn't scan. But it usually closes in the first several hours to a few days of life. But when a baby is first born, that opening is still there, and the pulmonary vascular resistance at the moment of birth is still going to be high. It takes a little bit of time for it to drop. You want it to drop quickly, because that's how you start to oxygenate blood, so now your lungs are the organ of oxygenation, and so you need them to be able to get blood into their lungs to oxygenate, but it takes a little bit of time for that pulmonary vascular resistance to drop. And so when a baby first comes out, they will still have some of that blood going through the pulmonary artery, crossing that ductus arteriosus, and going back into the stomach circulation. But now your lungs are actually oxygenating, right? So during fetal circulation, the oxygen saturation of that whole system is going to be about the same, because the lungs aren't oxygenated. So blood goes, blood comes into the baby through, in this case, in every case, blood goes into the baby through the umbilical vein, and it is oxygenated there. At that point, it is oxygenated coming into the umbilical vein from the placenta. At that point, everything in the baby is using oxygen. It's not in any way absorbing, it's not bringing it in from anywhere else. So everything in the baby is using oxygen, and it brings the oxygenated blood back out through the umbilical arteries. So you're going to have oxygenated blood at that point going in through a pulmonary vein and de-oxygen coming out through a pulmonary artery, pulmonary through your umbilical arteries. But in that case, the lungs are not going to be a organ of oxygenation. Once they're open and once the baby is not attached, they're placenta anymore, all of the oxygenation is coming from the lungs. So if you then have de-oxygenated blood going from the right side of your heart out the pulmonary arteries to go to your lungs, but the pulmonary vascular resistance is higher, then some of that blood's going to go through just like it was before, but some of it's not. And so you're going to have de-oxygenated blood being shunted from where it should be going in the lungs across that ductus arteriosus back into the stomach circulation. So then if you think about the aorta, the ductus arteriosus comes off what is before the ductus arteriosus. So in that little part of the ascending aorta that is before the ductus arteriosus, you have the blood supply to your right arm and the blood supply to your head. Everything else is going to be supplied after the ductus arteriosus. And so if you think about it. - So it's vessels, duct vessels. - Right. - In order, essentially, right. - And we could talk more about them if you want to. - No, but to make the point why where to sample it is. - Exactly. - They need to understand this part of it. - Right. So the blood vessels that supply your right arm are going to be coming off the ascending aorta before your ductus arteriosus. So that is going to be all blood that was going from your left heart that has all come directly from your pulmonary veins back into the left-sided circulation. Everything after that. So except for your head and your right arm, everything after that is going to see the influence of whatever shunted right to left across your ductus arteriosus. And so if you have increased pulmonary vascular resistance, that sat will be lower. If your cardiac anatomy is normal. - We'll say that the cardiac anatomy is normal. (laughing) That sat will be lower. Eventually they will match. - The pre and post. - Eventually your pre and post should match. But in the very beginning. - The right side. - Yeah, just so we can say that simply the left side and the right side will eventually match. - Catch up, yeah. - Is that a sign that the ductus is closed? Do you guys use that at all? - So it can be a sign that the ductus is closed. If you don't have a ductus arteriosus, then you don't have a pre and post ductal sat. - Fair. - So people will still try and measure them. But if you don't have a ductus arteriosus, then your pre and post ductal are going to be equal because there's nothing to shunt across. But it can, if they are equal, it can also just be a sign that your pulmonary vascular resistance has dropped and you have equal PQPS. - But if they were initially different? - If they are initially different. So if you are in-- - And now working towards each other, that means we're closing. - No, that means-- - Not necessarily. - So if they are initially different and working toward each other, the most likely explanation and actively working, so your post ductal is rising. That is more likely a sign that your pulmonary vascular resistance is dropping. - Okay. - Yeah. - What-- - They're exchanging this. - What do you do for a ductus has decided to not play the game and it's not closing? - For the ductus? In the very beginning, we wait. This is sort of a hot topic in neonatology and especially in pre-term neonatology. - You gotta change everything I learned in med school now? 'Cause I know the answer is, I had this question. - I think I know the answer to this too, which is weird. - So I'll tell you that we almost never do open legations anymore if that's what you're thinking. - Oh, God no. - But the short answer is we do close them. We usually give them some time to close on their own if they do not close on their own in the hospital setting. If we think we are having issues with the ductus arterioses, first of all, you'll have signs from the baby, so you will have a murmur. It's not generally that classic machine-like murmur that we learned about in med school, although it might be in older kids and adults, but in babies, it sounds more like just a systolic murmur. - Okay. - You'll have your murmur. You'll have signs of turbulent flow, and so you'll have widened pulse pressures. You'll see, you can not really see most of the time, but you can feel pulses in the baby's palms, and those are all signs that you have an open ductus arterioses or a patent ductus arterioses. This is never going to be something you wanna close during that initial high pulmonary vascular resistance time, because if you were to close it when your pulmonary vascular resistance is high during that initial kind of dropping of your pulmonary vascular resistance, what the body is using that ductus for is to shunt across, and if there's no word of shunt across, then you can have an acute pulmonary hypertensive crisis if you close off that opening. But later, after your pulmonary vascular resistance is dropped, you'll start to see the opposite through that ductus arterioses, so rather than right to left shunching, which lets you know that your pulmonary pressures are high, you'll start to see left to right shunting, and that is just the high systemic pressure shunting back toward the lungs, which can cause over time fluid overload pulmonary edema. Initially, when you have pulmonary over circulation, you'll see higher sets, but as you start to develop things like pulmonary edema, or even if you go way down the line, you can actually develop pulmonary hypertension from pulmonary over circulation, but in that middle point, that's the point at which we start to think about closing the ductus, when we are having difficulties with oxygenation because of pulmonary edema, when we have signs that we have turbulent flow with your wide and pulse pressures, and your pulmonary pulses, and I'm doing a really bad job explaining this, so that's right. - Are you doing it chemically or mechanically? - So, that's what I was getting at. So, when we first start to see it, so when we think of PDA might be starting to give us an issue, so we're starting to see signs of pulmonary edema, we will start doing it medically. We'll first try to do it medically, so there are multiple ways we can do this, the traditional one that you probably learned in men's schools, Indison. So, you can use Nsad, so Indison has sort of fallen out of favor. If you're going to use an Nsad, you're more likely the one is going to be ibuprofen. More recently, there's some data that Tylenol or acetaminophen can also work to close your ductus. And so, often times, because in the case of trying to close a ductus, babies will often have things like acute kidney injury, and that's from the turbulent flow, stealing blood away from the renal arteries. So, if you have acute kidney injury, you can make acute injury worse using an Nsad, and so, Tylenol has kind of come into favor because it has less side effects and less effects in the ways that our babies are already sick. And so, we'll usually start with either, usually now, Tylenol, but either Tylenol or ibuprofen, and we'll give sometimes more than one course of Tylenol or ibuprofen. And if our ductus is still open and still causing us issues, at that point, we move on to mechanical closure. And in recent years, we're not doing open PDA legations anymore. What we're mostly doing is catheter device closures. - Wire, yeah. - Very cool. - And-- - And when I say "we," these are dumb-- - Cardiologists. - Cardiologists. - Not us. - Cardiologists. (gentle music) (gentle music) (gentle music) (gentle music) (gentle music) (gentle music) You [BLANK_AUDIO]