WEBVTT 00:00:06.059 --> 00:00:09.800 Welcome to the bed. We'll go ahead and give you 00:00:09.800 --> 00:00:12.580 the story. This is all going to happen super 00:00:12.580 --> 00:00:46.950 fast. Welcome to the emergency room. Welcome 00:00:46.950 --> 00:00:50.469 back to the deep dive. Today, we are staring 00:00:50.469 --> 00:00:53.090 down the beast. And I say that with a healthy 00:00:53.090 --> 00:00:57.070 amount of, you know, respect, but let's be honest. 00:00:57.289 --> 00:01:00.390 Pediatric cardiac nursing is the monster under 00:01:00.390 --> 00:01:02.710 the bed for a lot of students. It really is. 00:01:02.990 --> 00:01:05.150 Even experienced nurses transitioning to the 00:01:05.150 --> 00:01:10.129 PICU find this stuff. daunting. It is massive. 00:01:10.230 --> 00:01:12.569 It's physically intimidating because you're dealing 00:01:12.569 --> 00:01:15.469 with these tiny humans. I mean, sometimes neonates 00:01:15.469 --> 00:01:17.370 weighing less than a bag of sugar. Right. But 00:01:17.370 --> 00:01:19.590 then intellectually, it's just so much to juggle. 00:01:19.650 --> 00:01:21.549 You have plumbing issues, which is the actual 00:01:21.549 --> 00:01:23.790 structure of the heart. You have electrical issues 00:01:23.790 --> 00:01:26.569 and then you have the pharmacology. Oh, the pharmacology. 00:01:26.629 --> 00:01:29.010 Which is a complete minefield because the safety 00:01:29.010 --> 00:01:32.230 margins in pediatrics are razor thin. What works 00:01:32.230 --> 00:01:34.909 for an adult can be a fatal dose for a neonate. 00:01:34.989 --> 00:01:37.329 Exactly. I was just looking at the stack of sources. 00:01:37.290 --> 00:01:39.409 as we have for today. And it's a stack. We've 00:01:39.409 --> 00:01:41.769 got this huge comprehensive textbook chapter 00:01:41.769 --> 00:01:44.269 on cardiovascular disorders, both congenital 00:01:44.269 --> 00:01:47.069 and acquired. And then we have these incredibly 00:01:47.069 --> 00:01:50.569 dense drug monographs for the real heavy hitters. 00:01:50.750 --> 00:01:53.829 We're talking alprosadil, indomethacin, furosemide, 00:01:53.989 --> 00:01:56.709 heparin. It's a lot of data to synthesize. It 00:01:56.709 --> 00:01:59.370 is a lot, but our mission today is to cut right 00:01:59.370 --> 00:02:00.930 through that noise. We are not just going to 00:02:00.930 --> 00:02:03.709 read slides here. We are going to cross reference 00:02:03.709 --> 00:02:06.689 the disease processes with that medication database 00:02:06.689 --> 00:02:10.009 to build what we call the Pareto 80 -20 guide. 00:02:10.169 --> 00:02:13.030 The Pareto principle. I love this. The idea that, 00:02:13.030 --> 00:02:15.490 what, 20 % of the causes lead to 80 % of the 00:02:15.490 --> 00:02:18.289 results. Precisely. So the goal is to give you, 00:02:18.330 --> 00:02:20.909 the listener, the 20 % of the cardiac concepts 00:02:20.909 --> 00:02:23.330 that are going to answer 80 % of your exam questions. 00:02:23.409 --> 00:02:25.409 And maybe more important. More importantly, yeah, 00:02:25.530 --> 00:02:27.439 prevent that. that failure to rescue scenario 00:02:27.439 --> 00:02:29.360 at the bedside. That's the real goal. Is moving 00:02:29.360 --> 00:02:31.539 from just memorizing lists of signs and symptoms 00:02:31.539 --> 00:02:34.340 to actually understanding the patterns. Exactly. 00:02:34.400 --> 00:02:37.539 If you understand the flow, the basic physics 00:02:37.539 --> 00:02:40.759 of the blood, you understand the defect. If you 00:02:40.759 --> 00:02:43.120 understand the defect, the medication suddenly 00:02:43.120 --> 00:02:45.199 makes perfect sense. You don't have to memorize 00:02:45.199 --> 00:02:48.400 that endomethacin closes the duct if you understand 00:02:48.400 --> 00:02:51.520 why the duct is open and why that's a problem 00:02:51.520 --> 00:02:54.659 in that specific kid. So we're orienting this 00:02:54.659 --> 00:02:56.800 whole deep dive for the learner today. Whether 00:02:56.800 --> 00:02:59.120 you're cramming for your finals, studying for 00:02:59.120 --> 00:03:02.020 the NCLEX, or prepping for your very first shift 00:03:02.020 --> 00:03:04.960 in the PICU, this is designed to keep you safe 00:03:04.960 --> 00:03:07.669 and get you those keywords. Yep. Let's do it. 00:03:07.830 --> 00:03:09.969 Let's dive in. So before we get into the alphabet 00:03:09.969 --> 00:03:13.189 soup of defects, the ASDs, VSDs, TOFs, you've 00:03:13.189 --> 00:03:14.469 pulled together what you're calling a master 00:03:14.469 --> 00:03:16.729 80 -20 map. I have. These are the high yield 00:03:16.729 --> 00:03:18.689 patterns that seem to apply across the board. 00:03:18.770 --> 00:03:20.629 Yeah. Can you walk us through this map? I feel 00:03:20.629 --> 00:03:22.409 like we can get this framework right. Everything 00:03:22.409 --> 00:03:24.590 else just kind of falls into place. Right. Before 00:03:24.590 --> 00:03:26.490 you even try to memorize a single defect, you 00:03:26.490 --> 00:03:28.210 have to understand the rules of the road. And 00:03:28.210 --> 00:03:30.650 pattern number one is simply the flow problem. 00:03:30.849 --> 00:03:33.969 It's hemodynamics. OK. And the golden rule here 00:03:33.969 --> 00:03:37.569 is simple physics. Blood follows the path of 00:03:37.569 --> 00:03:40.509 least resistance. Always. It's like water flowing 00:03:40.509 --> 00:03:42.789 downhill. It's just gravity. High pressure to 00:03:42.789 --> 00:03:45.069 low pressure. It's never going to decide to swim 00:03:45.069 --> 00:03:48.289 upstream unless something forces it to. Exactly. 00:03:48.469 --> 00:03:51.509 So think about a normal, healthy heart. The left 00:03:51.509 --> 00:03:54.150 side is the high pressure pumping system. And 00:03:54.150 --> 00:03:56.370 why is that? It has to pump to the whole body. 00:03:56.509 --> 00:03:58.830 The whole body. It has to push blood all the 00:03:58.830 --> 00:04:00.930 way down to your toes, up to your brain, out 00:04:00.930 --> 00:04:03.569 to your fingertips. It needs torque. It needs 00:04:03.569 --> 00:04:06.270 serious muscle. The right side, on the other 00:04:06.270 --> 00:04:08.990 hand, is a low pressure receiving system. It 00:04:08.990 --> 00:04:11.069 only has to get the blood next door. Just next 00:04:11.069 --> 00:04:13.069 door to the lungs. It's a very short trip. Low 00:04:13.069 --> 00:04:16.670 resistance. So just structurally, the left ventricle 00:04:16.670 --> 00:04:20.259 is physically thicker and stronger? Therefore, 00:04:20.579 --> 00:04:22.339 the pressure on the left is naturally going to 00:04:22.339 --> 00:04:24.040 be much higher than the pressure on the right. 00:04:24.180 --> 00:04:25.860 Correct. So just burn that gradient into your 00:04:25.860 --> 00:04:28.180 mind. Left is high, right is low. Now, what happens 00:04:28.180 --> 00:04:30.439 if there's a hole connecting them, a septal defect, 00:04:30.500 --> 00:04:33.060 for example? Physics takes over. Physics takes 00:04:33.060 --> 00:04:35.759 over. Blood is going to flow from the high pressure 00:04:35.759 --> 00:04:38.480 left side over to the low pressure right side. 00:04:38.759 --> 00:04:41.480 We call this a left to right shunt. Which means 00:04:41.480 --> 00:04:44.779 that nice oxygenated blood that was supposed 00:04:44.779 --> 00:04:47.199 to go out to the body it's already been to the 00:04:47.199 --> 00:04:50.019 lungs, it's pink, it's ready to go, is now sneaking 00:04:50.019 --> 00:04:52.300 back into the right side. And going back to the 00:04:52.300 --> 00:04:54.699 lungs for another lap. A totally unnecessary 00:04:54.699 --> 00:04:57.000 trick. It's inefficient, it's recirculating, 00:04:57.100 --> 00:04:59.980 and that right there gives you your first major 00:04:59.980 --> 00:05:03.019 category of defects, increased pulmonary blood 00:05:03.019 --> 00:05:06.259 flow. OK. These kids are pink because their blood 00:05:06.259 --> 00:05:08.660 is oxygenated. In fact, it's too oxygenated in 00:05:08.660 --> 00:05:11.100 the lungs. But their lungs are flooded. They 00:05:11.100 --> 00:05:13.139 are wet. They have pulmonary congestion. They're 00:05:13.139 --> 00:05:16.040 drowning in their own circulation. Pink and wet. 00:05:16.199 --> 00:05:18.180 OK, so that's side A of the map. What is the 00:05:18.180 --> 00:05:20.379 flip side? The reverse scenario. Yeah. What if 00:05:20.379 --> 00:05:23.180 there is an obstruction, a blockage, a kink in 00:05:23.180 --> 00:05:25.959 the hose that prevents blood from getting to 00:05:25.959 --> 00:05:28.019 the lungs in the first place? Like a stenotic 00:05:28.019 --> 00:05:30.920 valve. A stenotic pulmonic valve, for example. 00:05:31.240 --> 00:05:33.829 Or if the pressure on the right side somehow 00:05:33.829 --> 00:05:36.550 becomes effectively higher than the left for 00:05:36.550 --> 00:05:39.230 some reason, blood will shunt right to left. 00:05:39.550 --> 00:05:41.850 It completely skips the lungs. And if it skips 00:05:41.850 --> 00:05:44.129 the lungs, it never picks up oxygen, and it stays 00:05:44.129 --> 00:05:47.129 deoxygenated. It's blue blood. Exactly. That 00:05:47.129 --> 00:05:49.930 blue, unoxygenated blood goes straight from the 00:05:49.930 --> 00:05:52.009 right side through a defect to the left side 00:05:52.009 --> 00:05:54.850 and out to the body. These are your decreased 00:05:54.850 --> 00:05:56.970 pulmonary blood flow defects. And these are the 00:05:56.970 --> 00:05:58.910 blue babies. These are the blue babies. They 00:05:58.910 --> 00:06:02.360 are cyanotic. And this is almost always a medical 00:06:02.360 --> 00:06:05.139 emergency. Wow. Okay, so just that first distinction. 00:06:05.800 --> 00:06:08.819 Pink wet lungs versus blue dry lungs. That's 00:06:08.819 --> 00:06:11.920 the first major fork in the road. That simplifies 00:06:11.920 --> 00:06:13.920 things immensely. It's the master sorting hat 00:06:13.920 --> 00:06:15.819 for congenital defects. What's pattern number 00:06:15.819 --> 00:06:17.839 two on the map? Pattern number two is what I 00:06:17.839 --> 00:06:20.319 call the ductal dependent safety net. This is 00:06:20.319 --> 00:06:22.860 so critical for safety, and it's a concept that 00:06:22.860 --> 00:06:25.759 trips people up constantly on exams. We all have 00:06:25.759 --> 00:06:28.689 a ductus arteriosus as a fetus. It's a little 00:06:28.689 --> 00:06:31.029 vessel, a tunnel, that connects the pulmonary 00:06:31.029 --> 00:06:34.819 artery to the aorta. Its job is to bypass the 00:06:34.819 --> 00:06:37.379 lungs because the fetus isn't using them. It's 00:06:37.379 --> 00:06:39.420 supposed to close shortly after birth. We'll 00:06:39.420 --> 00:06:41.220 get into that whole fetal transition in a minute, 00:06:41.220 --> 00:06:44.259 but the core concept here is that for some of 00:06:44.259 --> 00:06:46.939 these babies, that little duct is the only thing 00:06:46.939 --> 00:06:49.420 keeping them alive. Exactly. If you have a severe 00:06:49.420 --> 00:06:51.680 obstruction, like a completely blocked valve, 00:06:52.199 --> 00:06:54.980 that duct might be the only way blood gets where 00:06:54.980 --> 00:06:57.600 it needs to go. It becomes a temporary life -saving 00:06:57.600 --> 00:07:00.060 bridge. So the safety item, the thing you can't 00:07:00.060 --> 00:07:02.139 miss... Is knowing when we need to keep it open. 00:07:02.220 --> 00:07:04.759 using prostaglandins and when we need to close 00:07:04.759 --> 00:07:07.579 it using something like endomethacin. You mix 00:07:07.579 --> 00:07:10.180 those two up. You close a duct on a baby who 00:07:10.180 --> 00:07:12.759 needs it open. You kill the patient. It's that 00:07:12.759 --> 00:07:15.339 stark. That is a sobering thought. But that's 00:07:15.339 --> 00:07:17.959 why we learn the mechanisms. It's not just memorization. 00:07:18.699 --> 00:07:21.060 Okay, pattern three. Pattern three is acquired 00:07:21.060 --> 00:07:23.160 inflammation. So now we're shifting gears. These 00:07:23.160 --> 00:07:24.959 are hearts that were built correctly. The plumbing 00:07:24.959 --> 00:07:27.500 was fine at birth. No holes, no valve issues. 00:07:27.899 --> 00:07:29.899 Everything was in the right place. But then something 00:07:29.899 --> 00:07:33.259 attacks the heart. Exactly. Inflammation attacks 00:07:33.259 --> 00:07:35.420 the system. Here we're talking about things like 00:07:35.420 --> 00:07:38.899 Kawasaki disease, rheumatic fever, infective 00:07:38.899 --> 00:07:42.519 endocarditis. So for these, the exam key isn't 00:07:42.519 --> 00:07:45.600 about shunts and pressures. It's about recognizing 00:07:45.600 --> 00:07:48.899 the triggers and the unique symptoms. Yes. It's 00:07:48.899 --> 00:07:51.899 pure pattern recognition. A history of strep 00:07:51.899 --> 00:07:54.379 throat two weeks ago for rheumatic fever, the 00:07:54.379 --> 00:07:57.379 classic strawberry tongue for Kawasaki. And those 00:07:57.379 --> 00:07:59.819 unique signs like Osler nodes for endocarditis, 00:08:00.100 --> 00:08:02.139 these are classic textbook symptoms that you 00:08:02.139 --> 00:08:05.079 actually see in real life, and exam writers love 00:08:05.079 --> 00:08:07.540 them. OK, that makes sense. And finally, pattern 00:08:07.540 --> 00:08:10.050 four on our map. Pattern four is the final destination. 00:08:10.209 --> 00:08:12.769 It's the consequence. If you don't manage the 00:08:12.769 --> 00:08:14.509 defects, if you don't manage the inflammation, 00:08:14.629 --> 00:08:17.350 you often end up at the same place. Heart failure. 00:08:17.470 --> 00:08:19.829 But in pediatrics, heart failure looks really 00:08:19.829 --> 00:08:21.589 different than in adults, right? So different. 00:08:21.629 --> 00:08:23.850 It's not just swollen ankles and shortness of 00:08:23.850 --> 00:08:26.930 breath. In an infant, it's growth failure. It's 00:08:26.930 --> 00:08:29.470 major feeding issues. It's that classic sign 00:08:29.470 --> 00:08:31.670 of sweating all they're eating because it's such 00:08:31.670 --> 00:08:35.769 hard work. OK, this map is fantastic. So flow 00:08:35.769 --> 00:08:38.879 problem. ductal dependence, acquired inflammation, 00:08:39.240 --> 00:08:42.210 and heart failure. Let's use that to unpack the 00:08:42.210 --> 00:08:44.389 plumbing a bit more. The sources start with the 00:08:44.389 --> 00:08:46.750 fetal to newborn transition. They do. And I feel 00:08:46.750 --> 00:08:48.830 like you really can't understand what's wrong 00:08:48.830 --> 00:08:51.070 if you don't know how it started. This is the 00:08:51.070 --> 00:08:53.970 essential context. Absolutely. In utero, the 00:08:53.970 --> 00:08:57.169 fetus is living in a fluid environment. The lungs 00:08:57.169 --> 00:08:59.690 are basically these little fluid -filled bags. 00:08:59.789 --> 00:09:01.970 They aren't doing any gas exchange. The placenta 00:09:01.970 --> 00:09:03.950 is the lung. The placenta is the lung, the kidney, 00:09:04.070 --> 00:09:05.970 the gut. It does everything. So the lungs and 00:09:05.970 --> 00:09:08.549 utero are collapsed, high pressure, high resistance 00:09:08.549 --> 00:09:11.629 zones. The fetal heart is brilliantly designed 00:09:11.629 --> 00:09:13.769 to bypass them entirely because sending a lot 00:09:13.769 --> 00:09:15.450 of blood there is just a waste of energy. And 00:09:15.450 --> 00:09:17.830 it does that using two key shortcuts, the trap 00:09:17.830 --> 00:09:20.850 doors. Shortcut number one is the Foreman Oval. 00:09:21.269 --> 00:09:23.990 This is a literal door, a flap between the right 00:09:23.990 --> 00:09:26.700 atrium and the left atrium. So blood comes back 00:09:26.700 --> 00:09:29.379 from the body into the right side, hits that 00:09:29.379 --> 00:09:31.940 door, and flows straight across to the left side, 00:09:32.200 --> 00:09:34.139 completely bypassing the right ventricle and 00:09:34.139 --> 00:09:36.399 the lungs. Smart. And shortcut number two is 00:09:36.399 --> 00:09:38.700 the ductus arteriosus, which we just mentioned. 00:09:39.139 --> 00:09:41.240 This is that tunnel connecting the pulmonary 00:09:41.240 --> 00:09:43.720 artery directly to the aorta. So even the small 00:09:43.720 --> 00:09:45.500 amount of blood that does get into the pulmonary 00:09:45.500 --> 00:09:48.200 artery gets shunted through this tunnel into 00:09:48.200 --> 00:09:51.000 the aorta and then out to the body, again, bypassing 00:09:51.000 --> 00:09:53.399 the lungs. So in a perfect world, the baby is 00:09:53.399 --> 00:09:56.460 born. takes that first big screaming breath, 00:09:56.860 --> 00:09:59.259 the lungs expand like a popped balloon. And the 00:09:59.259 --> 00:10:01.700 pressure inside the lungs just plummets. It goes 00:10:01.700 --> 00:10:04.480 from a high resistance system to a super low 00:10:04.480 --> 00:10:07.700 resistance system. Blood suddenly rushes into 00:10:07.700 --> 00:10:11.220 the lungs. And that cascade of events slams those 00:10:11.220 --> 00:10:13.620 fetal doors shut. It does. The rush of blood 00:10:13.620 --> 00:10:15.700 returning from the newly opened lungs raises 00:10:15.700 --> 00:10:18.500 the pressure in the left atrium, which physically 00:10:18.500 --> 00:10:21.929 pushes that form an oval door shut. At the same 00:10:21.929 --> 00:10:25.049 time, oxygen levels skyrocket in the blood, and 00:10:25.049 --> 00:10:27.490 the mother's prostaglandins are cut off, which 00:10:27.490 --> 00:10:30.009 signals the ductus arteriosus muscle to constrict 00:10:30.009 --> 00:10:32.529 and close down, usually within a day or two. 00:10:32.769 --> 00:10:34.929 But when they don't close, or when the heart 00:10:34.929 --> 00:10:36.950 structure is so abnormal that it forces them 00:10:36.950 --> 00:10:39.769 to stay functional, that's the entire basis of 00:10:39.769 --> 00:10:41.230 congenital heart disease. It's the whole ball 00:10:41.230 --> 00:10:44.049 game. Okay, let's finally get into the defects 00:10:44.049 --> 00:10:46.149 themselves. Yeah. We'll start with our first 00:10:46.149 --> 00:10:49.690 category from the map, the pink puffers. the 00:10:49.690 --> 00:10:52.830 increased pulmonary blood flow group. What are 00:10:52.830 --> 00:10:55.809 the main players here? So this is your atrial 00:10:55.809 --> 00:10:59.389 septal defect ASD, your ventricular septal defect 00:10:59.389 --> 00:11:03.909 VSD, the patent ductus arteriosus PDA. and a 00:11:03.909 --> 00:11:06.049 more complex one called the atrioventricular 00:11:06.049 --> 00:11:08.809 AV canal. And the unifying theme for all of them 00:11:08.809 --> 00:11:10.669 is that left to right shunt we talked about, 00:11:10.750 --> 00:11:13.210 high pressure to low pressure. Exactly. Let's 00:11:13.210 --> 00:11:15.490 take the ventricular septal defect, VSD. It's 00:11:15.490 --> 00:11:17.470 the most common congenital heart defect there 00:11:17.470 --> 00:11:19.870 is. You simply have a hole in the wall, the septum, 00:11:19.970 --> 00:11:22.230 between the ventricles. So when the big, strong 00:11:22.230 --> 00:11:24.509 left ventricle squeezes to pump blood out to 00:11:24.509 --> 00:11:28.009 the body, because of that hole, a jet of high 00:11:28.009 --> 00:11:31.190 pressure oxygenated blood shoots back across 00:11:31.190 --> 00:11:33.549 into the right ventricle. does the right ventricle 00:11:33.549 --> 00:11:36.009 send all its blood? Straight to the lungs. So 00:11:36.009 --> 00:11:37.830 now the poor lungs are getting the normal amount 00:11:37.830 --> 00:11:39.129 of blood they're supposed to get from the right 00:11:39.129 --> 00:11:42.090 side. PLUS, this extra high pressure jet of blood 00:11:42.090 --> 00:11:45.129 from the left side. The entire pulmonary vascular 00:11:45.129 --> 00:11:47.490 system gets flooded and overloaded. So clinically, 00:11:47.789 --> 00:11:49.590 what does the nurse see at the bedside? What 00:11:49.590 --> 00:11:52.899 are the need -to -know findings for a VSD? You 00:11:52.899 --> 00:11:55.279 see signs of heart failure because the heart 00:11:55.279 --> 00:11:57.159 is working double time and it's inefficient. 00:11:57.419 --> 00:11:59.700 You'll see tachypnea, the breathing fast, sometimes 00:11:59.700 --> 00:12:02.960 60, 70, 80 breaths a minute, just trying to compensate 00:12:02.960 --> 00:12:05.860 for all that fluid. And a fast heart rate. Tachycardia, 00:12:06.039 --> 00:12:09.779 absolutely. But a huge one for exams and for 00:12:09.779 --> 00:12:13.500 real life clinical practice is frequent respiratory 00:12:13.500 --> 00:12:16.059 infections. Because wet lungs are just a perfect 00:12:16.059 --> 00:12:18.379 breeding ground for bacteria. It's a swamp. It's 00:12:18.379 --> 00:12:22.110 a swamp, exactly. Fluid stasis leads to pneumonia 00:12:22.110 --> 00:12:24.610 and bronchitis. So if you have a baby that's 00:12:24.610 --> 00:12:26.649 coming back to the clinic over and over with 00:12:26.649 --> 00:12:29.029 recurrent pneumonia, somebody needs to put a 00:12:29.029 --> 00:12:30.789 stethoscope on their chest and listen to their 00:12:30.789 --> 00:12:32.409 heart. And what are we going to hear? With a 00:12:32.409 --> 00:12:35.370 VSD, you're going to hear a loud, harsh, often 00:12:35.370 --> 00:12:38.470 holosostolic murmur best heard at the left sternal 00:12:38.470 --> 00:12:41.549 border. It's harsh because of that huge pressure 00:12:41.549 --> 00:12:44.149 gradient we talked about. High pressure forcing 00:12:44.149 --> 00:12:46.690 blood through a small hole makes a lot of noise. 00:12:46.919 --> 00:12:49.100 OK, that makes sense. Now let's talk about the 00:12:49.100 --> 00:12:52.460 patent ductus arteriosus, PDA. This is that fetal 00:12:52.460 --> 00:12:54.399 tunnel that just never got the memo to close. 00:12:54.539 --> 00:12:57.820 Right. Remember, in the fetus, this shunts blood 00:12:57.820 --> 00:12:59.799 away from the lungs, from the pulmonary artery 00:12:59.799 --> 00:13:03.019 to the aorta. But after birth, the pressures 00:13:03.019 --> 00:13:06.440 in the body flip. The aorta is now the high pressure 00:13:06.440 --> 00:13:09.360 hose. The pulmonary artery is low pressure. So 00:13:09.360 --> 00:13:12.679 the blood flow. reverses direction through the 00:13:12.679 --> 00:13:15.419 duct. Exactly. Now, blood shunts backwards from 00:13:15.419 --> 00:13:17.779 the high -pressure aorta into the low -pressure 00:13:17.779 --> 00:13:20.179 pulmonary artery. So once again, you're flooding 00:13:20.179 --> 00:13:22.179 the lungs with extra blood. And this has very 00:13:22.179 --> 00:13:24.679 specific murmur, right? This is a key word I 00:13:24.679 --> 00:13:26.700 see in every single review book. It is. It's 00:13:26.700 --> 00:13:30.039 the classic exam descriptor, a continuous machinery 00:13:30.039 --> 00:13:32.659 -like murmur. It sounds like a washing machine 00:13:32.659 --> 00:13:34.600 or a humming engine because blood is flowing 00:13:34.600 --> 00:13:37.019 through it during both systole and diastole. 00:13:37.200 --> 00:13:39.980 And another key assessment finding is wide pulse 00:13:39.980 --> 00:13:43.159 pressure. Explain that. Why does the pulse pressure 00:13:43.159 --> 00:13:46.039 widen with the PDA? Okay, so pulse pressure is 00:13:46.039 --> 00:13:48.159 simply the difference between your systolic pressure 00:13:48.159 --> 00:13:51.320 and your diastolic pressure. In a PDA, blood 00:13:51.320 --> 00:13:53.879 is constantly leaking out of the aorta during 00:13:53.879 --> 00:13:56.960 diastole, the heart's resting phase, and flowing 00:13:56.960 --> 00:13:59.139 back into the pulmonary artery. So the pressure 00:13:59.139 --> 00:14:01.460 in the aorta drops while the heart is resting? 00:14:01.600 --> 00:14:05.120 It drops significantly. This causes the diastolic 00:14:05.120 --> 00:14:07.899 blood pressure to be very low. So you might see 00:14:07.899 --> 00:14:11.639 a blood pressure of, say, 100 over 40. That gap 00:14:11.639 --> 00:14:15.009 between 140 is huge. wide pulse pressure. Got 00:14:15.009 --> 00:14:17.149 it. Okay, now we need to integrate the pharmacology. 00:14:17.210 --> 00:14:18.990 We mentioned endomethacin at the very beginning. 00:14:19.210 --> 00:14:21.750 This is where it lives. This is its home. This 00:14:21.750 --> 00:14:24.629 is the medical closure strategy. If we have a 00:14:24.629 --> 00:14:27.289 premature infant with a symptomatic PDA, their 00:14:27.289 --> 00:14:29.090 lungs are wet, they're in heart failure, they 00:14:29.090 --> 00:14:30.690 can't get off the ventilator, we don't want to 00:14:30.690 --> 00:14:33.470 do surgery if we can avoid it. So we give IV 00:14:33.470 --> 00:14:37.009 endomethacin or another NSAA like ibuprofenylacine. 00:14:37.190 --> 00:14:40.129 And these are NSAIDs. How do they work to close 00:14:40.129 --> 00:14:42.190 the duct? So prostaglandins are the chemicals 00:14:42.190 --> 00:14:44.899 that naturally keep the duct open in the fetus. 00:14:45.399 --> 00:14:48.159 NSI's work by inhibiting prostaglandin synthesis. 00:14:48.659 --> 00:14:50.700 You cut off the supply of prostaglandins and 00:14:50.700 --> 00:14:53.320 the muscle in the ductus arteriosus constricts 00:14:53.320 --> 00:14:55.600 and closes. But we have to be really, really 00:14:55.600 --> 00:14:58.100 careful with endomethacin. I was looking at the 00:14:58.100 --> 00:15:01.799 drug monograph. This is not a benign drug for 00:15:01.799 --> 00:15:04.779 a tiny baby. No, it has huge risks. It works 00:15:04.779 --> 00:15:07.250 by constricting blood vessels. That's great for 00:15:07.250 --> 00:15:08.889 the duck, but it doesn't just work on the duck. 00:15:09.129 --> 00:15:11.629 It can potentially constrict other vital vascular 00:15:11.629 --> 00:15:14.070 beds, specifically the kidneys and the gut. So 00:15:14.070 --> 00:15:15.950 the need -to -know safety checks are absolutely 00:15:15.950 --> 00:15:18.350 vital here. Absolutely. Before and during the 00:15:18.350 --> 00:15:20.289 administration of endomethacin, you are watching 00:15:20.289 --> 00:15:23.429 two organ systems like a hawk. Number one, the 00:15:23.429 --> 00:15:26.870 kidneys, is the patient peeing. Because endomethacin 00:15:26.870 --> 00:15:29.590 can cause renal vasoconstriction, leading to 00:15:29.590 --> 00:15:32.409 oliguria, low urine output, or even acute renal 00:15:32.409 --> 00:15:34.669 failure. You're tracking urine output hourly. 00:15:34.840 --> 00:15:37.659 hourly, and checking the creatinine before you 00:15:37.659 --> 00:15:41.220 even start. And number two, the gut. You're watching 00:15:41.220 --> 00:15:44.159 for any sign of GI bleeding, abdominal distension, 00:15:44.200 --> 00:15:46.940 or bloody stools. Because if you restrict blood 00:15:46.940 --> 00:15:49.820 flow to a preemie's already fragile gut, you 00:15:49.820 --> 00:15:52.799 can cause a devastating condition called necrotizing 00:15:52.799 --> 00:15:56.179 enterocolitis. NEC. That is a critical safety 00:15:56.179 --> 00:15:58.379 point. So it's contraindicated in a patient with 00:15:58.379 --> 00:16:02.139 an active GI bleed, suspected NEC, or significant 00:16:02.139 --> 00:16:04.000 renal impairment. You have to check the labs, 00:16:04.139 --> 00:16:06.379 the creatinine, the platelets before you ever 00:16:06.379 --> 00:16:09.419 hang that bag. 100%. It's a non -negotiable safety 00:16:09.419 --> 00:16:11.139 check. OK. That's a perfect cross -reference. 00:16:11.440 --> 00:16:13.919 Now let's move to the, well, the scarier side 00:16:13.919 --> 00:16:17.559 of the spectrum. The blue babies. decreased pulmonary 00:16:17.559 --> 00:16:19.879 blood flow. Yeah, these are your cyanotic defects. 00:16:20.320 --> 00:16:22.340 The core problem here is that the plumbing is 00:16:22.340 --> 00:16:24.379 blocked on the right side of the heart. The blood 00:16:24.379 --> 00:16:26.980 literally cannot get to the lungs, so it's forced 00:16:26.980 --> 00:16:28.779 to find another way out. And that other way is 00:16:28.779 --> 00:16:31.019 to cross over to the left side, unoxygenated, 00:16:31.240 --> 00:16:32.840 and get pumped out to the body. Exactly. The 00:16:32.840 --> 00:16:36.080 absolute star of the show here is Tetralogy of 00:16:36.080 --> 00:16:41.279 Fallot, or TOF. It feels like every test has 00:16:41.279 --> 00:16:44.659 at least one Tetralogy question. It's the exam, 00:16:44.960 --> 00:16:47.100 darling. It really is. It's the classic cyanotic 00:16:47.100 --> 00:16:49.639 defect. And it seems complex, but it actually 00:16:49.639 --> 00:16:52.299 follows a pretty clear logic. It's four distinct 00:16:52.299 --> 00:16:55.039 defects that occur together in one package. You 00:16:55.039 --> 00:16:57.080 have to know the four components. OK, break them 00:16:57.080 --> 00:16:59.240 down for us. The key problem, the one that drives 00:16:59.240 --> 00:17:02.639 everything else, is number one. Pulmonic stenosis. 00:17:03.240 --> 00:17:05.779 The pulmonic valve, the door leading out of the 00:17:05.779 --> 00:17:08.119 right ventricle to the lungs, is narrowed and 00:17:08.119 --> 00:17:10.160 stiff. It's an obstruction. A kink in the hose. 00:17:10.319 --> 00:17:12.660 A kink in the hose. Because the right ventricle 00:17:12.660 --> 00:17:15.500 has to work so hard to push blood past the stenosis, 00:17:15.839 --> 00:17:18.190 you get defect number two. right ventricular 00:17:18.190 --> 00:17:21.029 hypertrophy, the muscle gets thick and beefy 00:17:21.029 --> 00:17:23.029 from constantly working against high resistance. 00:17:23.029 --> 00:17:25.430 Like a bodybuilder. Exactly. Then you have defect 00:17:25.430 --> 00:17:28.250 number three, a VSD, a hole between the ventricles. 00:17:28.789 --> 00:17:31.309 And finally, defect number four is the overriding 00:17:31.309 --> 00:17:33.490 aorta. The aorta is kind of shifted over and 00:17:33.490 --> 00:17:35.529 sits right on top of the VSD, so it's getting 00:17:35.529 --> 00:17:37.829 blood from both the right and left ventricles. 00:17:37.990 --> 00:17:40.450 So it's grabbing both blue blood from the right 00:17:40.450 --> 00:17:43.250 and pink blood from the left. Correct. And the 00:17:43.250 --> 00:17:45.589 severity of the symptoms, how blue the baby is, 00:17:45.769 --> 00:17:48.170 depends almost entirely on that first one, the 00:17:48.170 --> 00:17:50.529 degree of pulmonic stenosis. That makes sense. 00:17:50.710 --> 00:17:53.250 If the stenosis is really tight, very little 00:17:53.250 --> 00:17:56.130 blood can get to the lungs and the baby is profoundly 00:17:56.130 --> 00:17:58.589 cyanotic. If it's mild, they might just look 00:17:58.589 --> 00:18:00.250 a little dusky when they cry. They're called 00:18:00.250 --> 00:18:03.269 pink tets. But the classic clinical feature you 00:18:03.269 --> 00:18:05.910 absolutely need to know is the TET spell, or 00:18:05.910 --> 00:18:08.369 hypercyanotic spell. Walk us through a TET spell. 00:18:08.470 --> 00:18:10.529 What happens? What triggers it? It typically 00:18:10.529 --> 00:18:13.869 happens during times when oxygen demand suddenly 00:18:13.869 --> 00:18:16.529 exceeds supply. So think about it crying, feeding, 00:18:17.230 --> 00:18:20.670 a painful procedure like an IV start, or even 00:18:20.670 --> 00:18:22.779 having a bowel movement. Anything that stresses 00:18:22.779 --> 00:18:25.480 the baby out. Any stressor. The infant gets upset, 00:18:25.799 --> 00:18:28.400 adrenaline surges, and this causes the smooth 00:18:28.400 --> 00:18:30.920 muscle in the right ventricular outflow tract. 00:18:31.259 --> 00:18:33.440 The area right below that already tight pulmonic 00:18:33.440 --> 00:18:35.980 valve to spasm, it just clamps down hard. So 00:18:35.980 --> 00:18:37.900 the door to the lungs, which was already barely 00:18:37.900 --> 00:18:41.039 open, basically slams shut. Effectively, yes. 00:18:41.079 --> 00:18:43.319 So now almost no blood can get to the lungs. 00:18:44.099 --> 00:18:46.380 All that blue blood in the right ventricle has 00:18:46.380 --> 00:18:48.579 nowhere to go but right to left. through the 00:18:48.579 --> 00:18:51.759 VSD, and out the overriding aorta to the body. 00:18:51.980 --> 00:18:55.900 And the baby turns. Deeply blue. The oxygen saturation 00:18:55.900 --> 00:18:58.460 plummets to the 40s or 50s. They become limp. 00:18:58.740 --> 00:19:01.279 And they can even have a seizure or lose consciousness. 00:19:01.440 --> 00:19:03.759 It is terrifying to witness. And the nursing 00:19:03.759 --> 00:19:05.759 action. This is on every single exam. The very 00:19:05.759 --> 00:19:09.019 first thing you do is what? You put the infant 00:19:09.019 --> 00:19:11.420 in the knee -to -chest position. Or, if they're 00:19:11.420 --> 00:19:13.680 an older child, they will often do this instinctively. 00:19:13.900 --> 00:19:15.980 They'll squat down on the playground. Why does 00:19:15.980 --> 00:19:19.569 that work? It seems so simple, but the physiology 00:19:19.569 --> 00:19:22.309 behind it is actually fascinating. It's pure, 00:19:22.490 --> 00:19:25.049 beautiful physics. By squishing their legs up 00:19:25.049 --> 00:19:27.490 against their chest or by squatting, you kink 00:19:27.490 --> 00:19:30.309 the femoral arteries in the legs. This dramatically 00:19:30.309 --> 00:19:33.309 increases the systemic vascular resistance, SVR. 00:19:33.509 --> 00:19:35.250 So you're increasing the pressure on the left 00:19:35.250 --> 00:19:37.309 side of the heart, in the aorta and the left 00:19:37.309 --> 00:19:39.809 ventricle. Exactly. You are making it harder 00:19:39.809 --> 00:19:42.009 for the left ventricle to pump blood out to the 00:19:42.009 --> 00:19:45.170 body. This creates back pressure. That back pressure 00:19:45.170 --> 00:19:48.029 pushes back against the VSD. So it makes it harder 00:19:48.029 --> 00:19:50.009 for the blue blood to shunt from right to left. 00:19:50.170 --> 00:19:53.089 Yes. It reduces the right to left shunt and essentially 00:19:53.089 --> 00:19:56.109 forces more blood to take the only other path 00:19:56.109 --> 00:19:59.660 available through that tight, spasming pulmonary 00:19:59.660 --> 00:20:02.680 artery to the lungs. It's a mechanical manipulation 00:20:02.680 --> 00:20:05.079 of pressure. It's absolutely brilliant. It buys 00:20:05.079 --> 00:20:07.339 you time. It buys you critical time. But then 00:20:07.339 --> 00:20:09.460 pharmacologically, we treat those spells with 00:20:09.460 --> 00:20:12.900 morphine and, from our medication list, propranolol. 00:20:13.220 --> 00:20:15.650 Ah. Another cross -reference to our med stack. 00:20:15.990 --> 00:20:18.670 Why propranolol? It's a beta blocker. It is. 00:20:18.690 --> 00:20:21.890 It's a non -selective beta blocker. In this specific 00:20:21.890 --> 00:20:24.509 case, it has a magical effect of relaxing the 00:20:24.509 --> 00:20:27.690 smooth muscle spasm in that right ventricular 00:20:27.690 --> 00:20:30.650 outflow tract, the area called the infundibulum. 00:20:31.009 --> 00:20:32.890 It literally helps open the door to the lungs 00:20:32.890 --> 00:20:35.269 a little wider. And the morphine. Morphine is 00:20:35.269 --> 00:20:38.089 a central nervous system depressant. It calms 00:20:38.089 --> 00:20:40.769 the child, which is crucial because crying and 00:20:40.769 --> 00:20:43.250 agitation increase pulmonary vascular resistance. 00:20:43.150 --> 00:20:46.170 and make the spell worse. It sedates them and 00:20:46.170 --> 00:20:48.490 reduces the respiratory drive slightly, which 00:20:48.490 --> 00:20:50.789 helps to break that vicious cycle of sympathetic 00:20:50.789 --> 00:20:53.990 surge and hypoxia. So need a chest to increase 00:20:53.990 --> 00:20:57.230 systemic resistance, propranolol to decrease 00:20:57.230 --> 00:21:00.029 the pulmonary resistance spasm, and morphine 00:21:00.029 --> 00:21:04.230 to calm the system down. Got it. What about tricuspid 00:21:04.230 --> 00:21:07.369 atresia? That's another blue baby one. Tricuspid 00:21:07.369 --> 00:21:09.569 atresia is basically a do not enter sign on the 00:21:09.569 --> 00:21:12.619 heart. The tricuspid valve, the door between 00:21:12.619 --> 00:21:15.180 the right atrium and the right ventricle simply 00:21:15.180 --> 00:21:17.279 fails to develop. It's a solid sheet of tissue. 00:21:17.579 --> 00:21:19.720 So blood can't get to the lungs the normal way 00:21:19.720 --> 00:21:22.000 at all? Not at all. There is no path from the 00:21:22.000 --> 00:21:24.079 right atrium to the right ventricle. So how do 00:21:24.079 --> 00:21:26.309 these babies survive even for a minute? They 00:21:26.309 --> 00:21:28.890 absolutely require two things. One, they need 00:21:28.890 --> 00:21:32.230 a hole in ASD or a VSD to allow blood to mix 00:21:32.230 --> 00:21:35.170 and get over to the left side. And two, crucially, 00:21:35.569 --> 00:21:37.930 they require the ductus arteriosus to stay open. 00:21:38.230 --> 00:21:39.930 That's the only way blood can get to the lungs 00:21:39.930 --> 00:21:42.450 through the back door from the aorta. This is 00:21:42.450 --> 00:21:44.730 the definition of a ductal -dependent lesion. 00:21:45.190 --> 00:21:47.410 So if that duct closes? The pathway to the lungs 00:21:47.410 --> 00:21:49.890 is gone and the baby will die. Which brings us 00:21:49.890 --> 00:21:51.950 directly to the opener on our medication list, 00:21:52.329 --> 00:21:55.519 oprostidil. Alprostidyl, also known by its brand 00:21:55.519 --> 00:22:00.579 name, ProstenVR, is Prostaglandin E1. This drug 00:22:00.579 --> 00:22:03.799 is a lifeline. Its sole mission in this context 00:22:03.799 --> 00:22:06.859 is to maintain the patency of the ductus arteriosus. 00:22:07.140 --> 00:22:09.519 It keeps that tunnel open until a surgeon can 00:22:09.519 --> 00:22:12.420 create a more permanent solution. But looking 00:22:12.420 --> 00:22:14.980 at the monograph for alprostidyl, this is a very 00:22:14.980 --> 00:22:17.519 high -stakes medication. The side effect profile 00:22:17.519 --> 00:22:21.390 is scary. It is. The number one absolute need 00:22:21.390 --> 00:22:24.430 -to -know clinical pearl for alprostidyl is apnea. 00:22:24.700 --> 00:22:27.640 They just stop breathing. Yes. It happens in 00:22:27.640 --> 00:22:30.359 about 10 to 12 percent of neonates, and it usually 00:22:30.359 --> 00:22:32.259 happens in the first hour of starting the infusion. 00:22:32.519 --> 00:22:34.920 It has a direct suppressive effect on the respiratory 00:22:34.920 --> 00:22:37.099 center in the brain stem. So you don't just hang 00:22:37.099 --> 00:22:39.279 the bag, set the pump, and walk away. You never 00:22:39.279 --> 00:22:41.359 ever walk away. You hang the bag and you stand 00:22:41.359 --> 00:22:43.559 there with the intubation kit and ambu bag ready 00:22:43.559 --> 00:22:46.319 to go. You must have ventilatory assistance immediately 00:22:46.319 --> 00:22:48.460 available. You are essentially anticipating a 00:22:48.460 --> 00:22:50.759 potential respiratory arrest. That's a huge safety 00:22:50.759 --> 00:22:53.140 point. The monograph also mentions flushing as 00:22:53.140 --> 00:22:55.980 a side effect. Yes, cutaneous flushing the baby 00:22:55.980 --> 00:22:58.380 turning red is a very common side effect due 00:22:58.380 --> 00:23:01.299 to its vasodilatory properties. But here's a 00:23:01.299 --> 00:23:03.400 really important safety nuance from the source. 00:23:03.980 --> 00:23:06.759 If you are running the infusion through an umbilical 00:23:06.759 --> 00:23:10.539 artery catheter, a UAC, and you see intense flushing 00:23:10.539 --> 00:23:13.700 just on the baby's face or upper torso, you have 00:23:13.700 --> 00:23:16.079 to be careful. Why? Because it might mean the 00:23:16.079 --> 00:23:18.539 catheter tip is in the wrong spot. It might be 00:23:18.539 --> 00:23:20.559 sitting too high near the vessels that go to 00:23:20.559 --> 00:23:23.079 the head and arms and shooting a concentrated 00:23:23.079 --> 00:23:26.059 dose of this potent vasodilator straight into 00:23:26.059 --> 00:23:28.500 the cerebral circulation. You have to be aware 00:23:28.500 --> 00:23:31.509 of that. Wow. Okay. That is a fantastic clinical 00:23:31.509 --> 00:23:33.990 pearl. Let's move to the next category in the 00:23:33.990 --> 00:23:37.269 outline, the obstructive disorders. The kink 00:23:37.269 --> 00:23:39.369 in the garden hose group. Right. So the classic 00:23:39.369 --> 00:23:42.529 one here is coactation of the aorta. The aorta, 00:23:42.710 --> 00:23:44.890 the main artery leaving the heart, is pinched 00:23:44.890 --> 00:23:46.450 or narrowed. It's like someone stepped on the 00:23:46.450 --> 00:23:48.410 garden hose. This usually happens right after 00:23:48.410 --> 00:23:50.029 the arch, just past the point where the blood 00:23:50.029 --> 00:23:52.349 vessels branch off to the head and arms. OK. 00:23:52.349 --> 00:23:55.369 So if I'm visualizing the plumbing, the pinch 00:23:55.549 --> 00:23:57.710 is after the vessels that supply the head and 00:23:57.710 --> 00:24:00.009 arms, but before the vessels that go down to 00:24:00.009 --> 00:24:02.109 the legs and lower body. Exactly. So you have 00:24:02.109 --> 00:24:04.430 a massive traffic jam upstream from the pinch, 00:24:04.769 --> 00:24:07.150 an empty low -flow highway downstream. Which 00:24:07.150 --> 00:24:09.269 means you'd have bounding pulses and high blood 00:24:09.269 --> 00:24:11.869 pressure in the arms. Yes. High pressure to the 00:24:11.869 --> 00:24:14.589 brain, which can risk a stroke, and high BP in 00:24:14.589 --> 00:24:16.890 the arms. And then if you check the legs, you'll 00:24:16.890 --> 00:24:20.480 find weak or even absent... femoral pulses, cool 00:24:20.480 --> 00:24:23.119 skin, and low blood pressure. Before extremity 00:24:23.119 --> 00:24:25.839 blood pressure check. Exactly. This is the hallmark 00:24:25.839 --> 00:24:28.799 diagnostic sign. If you see a nurse taking a 00:24:28.799 --> 00:24:31.019 blood pressure on both an arm and a leg in a 00:24:31.019 --> 00:24:33.119 newborn, they are screening for coarctation. 00:24:33.640 --> 00:24:35.759 It's a standard screen in many nurseries now. 00:24:36.140 --> 00:24:39.200 If the upper extremity BP is significantly higher, 00:24:39.339 --> 00:24:42.160 like 15 to 20 points higher than the lower extremity 00:24:42.160 --> 00:24:45.200 BP, that's a huge red flag. That makes perfect 00:24:45.200 --> 00:24:47.460 physiological sense. Now what about the mixed 00:24:47.460 --> 00:24:50.900 defects? The source material calls these incompatible 00:24:50.900 --> 00:24:53.400 with life unless we intervene immediately. That 00:24:53.400 --> 00:24:56.619 sounds intense. They are chaotic and complex. 00:24:57.059 --> 00:24:59.240 The big one everyone needs to know is transposition 00:24:59.240 --> 00:25:02.440 of the great arteries, TGA. It's a fundamental 00:25:02.440 --> 00:25:05.640 wiring error. The pulmonary artery and the aorta 00:25:05.640 --> 00:25:08.519 are swapped. They're connected to the wrong ventricles. 00:25:08.740 --> 00:25:10.660 Completely wrong. The right ventricle, which 00:25:10.660 --> 00:25:12.779 is supposed to pump blue blood to the lungs, 00:25:13.019 --> 00:25:15.759 is instead connected to the aorta. So it pumps 00:25:15.759 --> 00:25:18.339 blue deoxygenated blood back out to the bottle. 00:25:18.440 --> 00:25:20.579 And the left ventricle. The left ventricle, which 00:25:20.579 --> 00:25:23.319 has the nice pink oxygenated blood returning 00:25:23.319 --> 00:25:25.740 from the lungs, is connected to the pulmonary 00:25:25.740 --> 00:25:28.259 artery. So it pumps that pink blood right back 00:25:28.259 --> 00:25:30.819 to the lungs again. It's two completely separate 00:25:30.819 --> 00:25:33.500 parallel loops that never meet. The body gets 00:25:33.500 --> 00:25:37.089 zero oxygenated blood. Unless you have a connection. 00:25:37.369 --> 00:25:40.690 You absolutely need a VSD, an ASD, or a patent 00:25:40.690 --> 00:25:43.549 ductus arteriosus to allow the blue blood and 00:25:43.549 --> 00:25:45.920 the pink blood to mix somewhere. This is another 00:25:45.920 --> 00:25:48.680 medical emergency where alprostidyl is the essential 00:25:48.680 --> 00:25:50.740 bridge to surgery. You have to keep that PDA 00:25:50.740 --> 00:25:53.259 open to allow for mixing. And the other big one 00:25:53.259 --> 00:25:55.539 mentioned is hypoplastic left heart syndrome, 00:25:55.740 --> 00:25:58.519 HLHS. This is one of the most severe and complex 00:25:58.519 --> 00:26:01.420 defects. The entire left side of the heart, the 00:26:01.420 --> 00:26:03.799 left ventricle, the mitral valve, the aortic 00:26:03.799 --> 00:26:07.059 valve, the ascending aorta is severely underdeveloped. 00:26:07.099 --> 00:26:10.640 It's tiny, sometimes nonexistent. It simply cannot 00:26:10.640 --> 00:26:13.259 support systemic circulation. So the treatment 00:26:13.259 --> 00:26:15.769 can't be a simple patch repair. No, these babies 00:26:15.769 --> 00:26:18.869 are critically ill from birth. They require a 00:26:18.869 --> 00:26:22.450 series of three very complex staged surgical 00:26:22.450 --> 00:26:25.809 procedures, the Norwood, the Glenn, and the Fontan, 00:26:26.029 --> 00:26:27.670 that happen over the first few years of life 00:26:27.670 --> 00:26:30.859 to completely replumb the heart. or they need 00:26:30.859 --> 00:26:33.200 a heart transplant. It's a very long and difficult 00:26:33.200 --> 00:26:36.039 road. Okay, let's pivot now to the acquired heart 00:26:36.039 --> 00:26:38.880 diseases. So again, these aren't structural defects 00:26:38.880 --> 00:26:41.619 from birth, but inflammatory attacks on a previously 00:26:41.619 --> 00:26:44.400 normal heart. Kawasaki disease is the big one 00:26:44.400 --> 00:26:47.880 here. Kawasaki disease is an acute systemic vasculitis. 00:26:48.019 --> 00:26:49.880 That's a fancy way of saying it's inflammation 00:26:49.880 --> 00:26:52.180 of the blood vessels, the arteries, the veins, 00:26:52.339 --> 00:26:54.619 the capillaries throughout the entire body. And 00:26:54.619 --> 00:26:56.660 for reasons we don't fully understand, it has 00:26:56.660 --> 00:26:59.359 a particular affinity for the coronary arteries. 00:26:59.559 --> 00:27:01.819 And it's the number one cause of acquired heart 00:27:01.819 --> 00:27:04.339 disease in kids in developed countries. It is. 00:27:04.460 --> 00:27:07.279 That's a huge deal. So what's the need to know 00:27:07.279 --> 00:27:10.019 for the exam? How do we spot this? The presentation 00:27:10.019 --> 00:27:12.380 seems very specific. It is. The diagnostic criteria 00:27:12.380 --> 00:27:15.130 are very clear. First, you need a high fever, 00:27:15.450 --> 00:27:18.450 usually over 102 degrees Fahrenheit or 39 Celsius. 00:27:19.029 --> 00:27:21.170 That lasts for more than five days and does not 00:27:21.170 --> 00:27:23.529 respond to antibiotics or antipyretics. That's 00:27:23.529 --> 00:27:25.849 the key trigger. Then you look for the associated 00:27:25.849 --> 00:27:28.430 symptoms, and the mnemonic is Cree rash. Okay, 00:27:28.509 --> 00:27:31.490 break down Cree rash for us. C is for conjunctivitis. 00:27:31.819 --> 00:27:34.319 It's a non -exudative conjunctivitis, meaning 00:27:34.319 --> 00:27:37.799 red eyes without any pus or drainage, just dry, 00:27:38.000 --> 00:27:41.599 red, irritated eyes. OK. R is for rash. It's 00:27:41.599 --> 00:27:44.140 usually the diffuse maculopapular rash, often 00:27:44.140 --> 00:27:46.980 on the trunk. A is for adenopathy, which means 00:27:46.980 --> 00:27:49.099 swollen lymph nodes, typically a single large 00:27:49.099 --> 00:27:51.720 one in the neck or cervical area. And S? S is 00:27:51.720 --> 00:27:54.259 for strawberry tongue. The tongue gets very red, 00:27:54.460 --> 00:27:56.680 swollen, and bumpy, like a strawberry. You can 00:27:56.680 --> 00:27:59.500 also see very red, cracked, peeling lips. And 00:27:59.500 --> 00:28:02.410 finally, H is for hands and feet. You see swelling 00:28:02.410 --> 00:28:04.490 and redness of the palms and soles, and then 00:28:04.490 --> 00:28:06.910 later, in the subacute phase, you get this characteristic 00:28:06.910 --> 00:28:08.950 peeling of the skin on the fingertips and toes. 00:28:09.430 --> 00:28:11.589 Strawberry tongue is such a classic key word. 00:28:11.890 --> 00:28:14.490 Now, the treatment for Kawasaki is really interesting 00:28:14.490 --> 00:28:17.190 because it breaks one of the cardinal rules of 00:28:17.190 --> 00:28:20.009 pediatrics. It absolutely does. We give aspirin. 00:28:20.269 --> 00:28:23.509 Ooh. We are taught from day one, you never give 00:28:23.509 --> 00:28:26.410 aspirin to kids. because of the risk of Ray's 00:28:26.410 --> 00:28:29.029 syndrome, which can cause devastating liver and 00:28:29.029 --> 00:28:31.289 brain damage, especially after a viral illness. 00:28:31.450 --> 00:28:34.670 Exactly. But Kawasaki disease is the one major 00:28:34.670 --> 00:28:37.869 exception to that rule. The benefit of its potent 00:28:37.869 --> 00:28:40.430 anti -inflammatory and anti -platelet effects 00:28:40.430 --> 00:28:43.829 far outweighs the risk of Ray's. We give very 00:28:43.829 --> 00:28:45.990 high doses of aspirin initially to cool down 00:28:45.990 --> 00:28:48.210 the inflammation and then a low dose for a long 00:28:48.210 --> 00:28:51.230 time after. And we also give IV, right? Intravenous 00:28:51.230 --> 00:28:54.369 immunoglobulin. Yes. High dose ID is the other 00:28:54.369 --> 00:28:56.329 cornerstone of treatment. We're essentially flooding 00:28:56.329 --> 00:28:58.750 the body with these pooled antibodies to dampen 00:28:58.750 --> 00:29:00.950 the patient's own overactive immune response. 00:29:01.250 --> 00:29:03.009 And the reason we do all this so aggressively 00:29:03.009 --> 00:29:05.549 is to prevent the crash risk. The coronary artery 00:29:05.549 --> 00:29:08.390 aneurysms. That's the ballgame. If you miss the 00:29:08.390 --> 00:29:10.470 diagnosis or you treat it too late after day 00:29:10.470 --> 00:29:13.109 10 of the fever, the child has a much higher 00:29:13.109 --> 00:29:15.569 risk of developing these dangerous aneurysms 00:29:15.569 --> 00:29:18.690 or weak bulging spots in their coronary arteries. 00:29:18.789 --> 00:29:20.809 Which can lead to blood clot. a heart attack, 00:29:21.329 --> 00:29:24.539 or long -term ischemic heart disease. It's wild 00:29:24.539 --> 00:29:26.299 to think about. A heart attack in a toddler? 00:29:26.480 --> 00:29:29.980 It happens. And that's why the long -term monitoring 00:29:29.980 --> 00:29:32.900 with echocardiograms is so crucial for these 00:29:32.900 --> 00:29:34.579 kids, sometimes for the rest of their lives. 00:29:34.700 --> 00:29:36.579 OK. Then we have rheumatic fever. This is the 00:29:36.579 --> 00:29:38.039 one that's connected to strep throat, right? 00:29:38.039 --> 00:29:41.900 Yes. This is an autoimmune reaction that is a 00:29:41.900 --> 00:29:45.579 delayed sequela of a group of a beta -hemolytic 00:29:45.579 --> 00:29:48.539 streptococcus pharyngeal infection. It usually 00:29:48.539 --> 00:29:51.200 happens about two to four weeks after an unfreeded 00:29:51.200 --> 00:29:53.900 or partially treated case of strep. So this is 00:29:53.900 --> 00:29:55.759 the kid who had a sore throat, maybe the parent 00:29:55.759 --> 00:29:57.640 gave them antibiotics for two days, they felt 00:29:57.640 --> 00:29:59.789 better, so they stopped the course early. That 00:29:59.789 --> 00:30:02.769 is the classic scenario. The antibodies the body 00:30:02.769 --> 00:30:04.990 made to fight the strep bacteria get confused 00:30:04.990 --> 00:30:07.130 and they start to cross -react and attack the 00:30:07.130 --> 00:30:10.009 body's own tissues, specifically the joints causing 00:30:10.009 --> 00:30:13.190 a migratory polyarthritis, the brain causing 00:30:13.190 --> 00:30:15.869 Sydenham's caria, which are these jerky involuntary 00:30:15.869 --> 00:30:19.950 movements, the skin causing a rash called erythema 00:30:19.950 --> 00:30:22.970 marginatum, and most importantly, the heart valves 00:30:22.970 --> 00:30:25.950 causing carditis. So the prevention is simply 00:30:25.950 --> 00:30:29.079 treating strep throat properly. Exactly. Prevention 00:30:29.079 --> 00:30:31.200 is everything here. Finish your full course of 00:30:31.200 --> 00:30:33.740 antibiotics. Penicillin is still the drug of 00:30:33.740 --> 00:30:36.420 choice. And we diagnose it using something called 00:30:36.420 --> 00:30:39.829 the modified Jones criteria. And briefly. Infective 00:30:39.829 --> 00:30:42.970 endocarditis. This is a direct bacterial or fungal 00:30:42.970 --> 00:30:45.289 infection of the inner lining of the heart, the 00:30:45.289 --> 00:30:47.509 endocardium, or the heart valves. You have to 00:30:47.509 --> 00:30:49.910 think about kids with pre -existing congenital 00:30:49.910 --> 00:30:52.549 heart defects or prosthetic valves. They are 00:30:52.549 --> 00:30:54.750 at very high risk because their blood flow is 00:30:54.750 --> 00:30:57.069 often turbulent. And that turbulent flow can 00:30:57.069 --> 00:31:00.049 damage the lining and create a rough spot. Exactly, 00:31:00.190 --> 00:31:02.470 a rough spot where bacteria can stick and grow, 00:31:02.589 --> 00:31:05.190 forming what's called a vegetation. But you also 00:31:05.190 --> 00:31:07.109 have to think about the entry points for the 00:31:07.109 --> 00:31:09.589 bacteria. Like dental work. Dental work is a 00:31:09.589 --> 00:31:11.849 major one. Bacteria from the mouth can get into 00:31:11.849 --> 00:31:14.190 the bloodstream during a cleaning or a procedure. 00:31:14.490 --> 00:31:16.970 That's why we give prophylactic antibiotics before 00:31:16.970 --> 00:31:19.769 the dentist to certain high -risk patients, like 00:31:19.769 --> 00:31:22.369 those with artificial valves or a previous history 00:31:22.369 --> 00:31:25.809 of endocarditis. And the exam keywords for endocarditis. 00:31:25.990 --> 00:31:28.049 The ones that always show up are ocelar nodes, 00:31:28.130 --> 00:31:30.819 which are painful red, tender nodules on the 00:31:30.819 --> 00:31:33.700 pads of the fingers and toes, and Janeway lesions, 00:31:33.940 --> 00:31:36.880 which are painless, hemorrhagic, flat spots on 00:31:36.880 --> 00:31:38.779 the palms of the hands and soles of the feet. 00:31:39.019 --> 00:31:41.099 Okay, we've covered the defects in the inflammation, 00:31:41.940 --> 00:31:44.240 but as you said, all roads can lead to heart 00:31:44.240 --> 00:31:46.900 failure. How does heart failure look in a baby 00:31:46.900 --> 00:31:49.970 versus an adult? It's so different. It is. In 00:31:49.970 --> 00:31:52.829 an adult, you're looking for jugular vein distension, 00:31:53.049 --> 00:31:55.410 JVD, or listening for crackles in the lungs, 00:31:55.690 --> 00:31:58.589 but you can't really see JVD in a chubby baby 00:31:58.589 --> 00:32:01.509 neck. In a baby, the signs are much subtler but 00:32:01.509 --> 00:32:04.430 very distinct. The very earliest sign is often 00:32:04.430 --> 00:32:06.970 unexplained tachycardia. The heart is just trying 00:32:06.970 --> 00:32:09.569 to beat faster to keep up. Exactly, to compensate 00:32:09.569 --> 00:32:12.329 for poor function. Then you'll see, to Chipney, 00:32:12.750 --> 00:32:15.869 fast breathing. But the hallmark, the thing the 00:32:15.869 --> 00:32:18.150 parents will almost always tell you about, is 00:32:18.150 --> 00:32:20.769 difficulty with feeding. The sweating with feed. 00:32:20.849 --> 00:32:23.589 That's the one. Scalp sweating. You have to think 00:32:23.589 --> 00:32:25.690 about it. Eating is the most aerobic exercise 00:32:25.690 --> 00:32:27.990 a newborn does. It's their marathon. If they 00:32:27.990 --> 00:32:30.509 can't finish a bottle, if they get sweaty and 00:32:30.509 --> 00:32:32.390 exhausted and start breathing fast after just 00:32:32.390 --> 00:32:35.470 an ounce or two, that is activity intolerance. 00:32:35.529 --> 00:32:37.589 That is a sign of heart failure. Which leads 00:32:37.589 --> 00:32:41.180 us perfectly into part C of our deep dive. development 00:32:41.180 --> 00:32:44.259 and milestones. How does all of this cardiac 00:32:44.259 --> 00:32:46.579 stress affect the growing child as a person? 00:32:46.660 --> 00:32:49.900 It has a massive impact. A baby is a metabolic 00:32:49.900 --> 00:32:52.619 engine that is designed for one thing to grow. 00:32:52.799 --> 00:32:55.339 If you are burning all of your available calories 00:32:55.339 --> 00:32:57.599 just trying to breathe and circulate blood because 00:32:57.599 --> 00:33:00.700 of a hole in your heart, you have no energy left 00:33:00.700 --> 00:33:03.720 over to put on weight. This is failure to thrive. 00:33:04.220 --> 00:33:05.619 So clinically, we're going to see them falling 00:33:05.619 --> 00:33:08.109 off the growth chart. Right. They'll drop from 00:33:08.109 --> 00:33:10.829 the 50th percentile for weight down to the fifth 00:33:10.829 --> 00:33:13.250 percentile. And the nursing intervention isn't 00:33:13.250 --> 00:33:16.369 just give medications. A huge part of it is nutritional 00:33:16.369 --> 00:33:19.289 management. We have to fortify the formula or 00:33:19.289 --> 00:33:21.710 breast milk to make it more calorie dense. Exactly. 00:33:22.089 --> 00:33:25.150 We'll increase it to 24 or 27 calories per ounce 00:33:25.150 --> 00:33:28.170 instead of the standard 20. We have to pack more 00:33:28.170 --> 00:33:30.930 punch into every single drop they can take in. 00:33:31.210 --> 00:33:33.259 And what about energy conservation? That's the 00:33:33.259 --> 00:33:34.940 other side of the coin. It's so important. We 00:33:34.940 --> 00:33:37.200 need to cluster our care. You don't want to be 00:33:37.200 --> 00:33:39.380 going in and waking the baby up every 15 minutes 00:33:39.380 --> 00:33:41.700 for vital signs if they desperately need to conserve 00:33:41.700 --> 00:33:45.079 energy. You do everything at once. Change the 00:33:45.079 --> 00:33:47.180 diaper. Check the vitals. Give the medicine. 00:33:47.640 --> 00:33:49.539 And then feed them. And then you let them rest. 00:33:49.819 --> 00:33:53.059 What about the psychosocial impact on the family 00:33:53.059 --> 00:33:56.180 and the child? The anxiety is real and profound. 00:33:56.480 --> 00:33:58.680 Imagine being a parent watching your child turn 00:33:58.680 --> 00:34:01.859 blue during a TED spell. It's traumatic. And 00:34:01.859 --> 00:34:03.880 for the child, there can be developmental delays. 00:34:04.319 --> 00:34:06.640 They might hit their motor milestones late because 00:34:06.640 --> 00:34:09.219 they're simply too tired to do tummy time or 00:34:09.219 --> 00:34:11.619 learn to crawl or walk. So it's our job to monitor 00:34:11.619 --> 00:34:14.440 for that. Absolutely. We have to monitor for 00:34:14.440 --> 00:34:16.739 those developmental red flags, but also support 00:34:16.739 --> 00:34:19.780 the family's coping mechanisms. We have to involve 00:34:19.780 --> 00:34:21.860 the child in their own care as they get older, 00:34:21.880 --> 00:34:24.219 and it's developmentally appropriate. Okay, let's 00:34:24.219 --> 00:34:26.679 do a really deep dive now into the medication 00:34:26.679 --> 00:34:28.300 module. We've touched on a few of these already, 00:34:28.599 --> 00:34:30.920 but I want to get granular with the safety data 00:34:30.920 --> 00:34:33.619 in these monographs because the exam questions 00:34:33.619 --> 00:34:36.980 so often hinge on the side effects or the specific 00:34:36.980 --> 00:34:39.179 nursing actions. Let's do it. So we've covered 00:34:39.179 --> 00:34:41.880 alprosodil, the opener, and endomethacin, the 00:34:41.880 --> 00:34:45.480 closer. Let's talk about furosemide lasix. The 00:34:45.480 --> 00:34:48.179 classic diuretic. Fluid overload management and 00:34:48.179 --> 00:34:51.039 heart failure. Right. It's a loop diuretic. It 00:34:51.039 --> 00:34:53.840 works by inhibiting sodium and chloride reabsorption 00:34:53.840 --> 00:34:56.420 in the loop of hemel in the kidneys. Bottom line, 00:34:56.860 --> 00:34:59.400 it makes you pee out a ton of fluid. But for 00:34:59.400 --> 00:35:01.780 the exam and for the bedside, you must remember 00:35:01.780 --> 00:35:04.420 the push rule. You have to push it slow. Very 00:35:04.420 --> 00:35:08.079 slow. The monograph explicitly states it. 0 .5 00:35:08.079 --> 00:35:10.260 milligrams per kilogram per minute. Not just 00:35:10.260 --> 00:35:13.420 slow, it's a specific rate. If you slam Lasix 00:35:13.420 --> 00:35:15.719 the Valk push or you give high doses too rapidly, 00:35:16.219 --> 00:35:18.659 you risk ototoxicity. Permanent hearing loss. 00:35:18.699 --> 00:35:22.070 Yeah. From a diuretic. Yes, it can be transient 00:35:22.070 --> 00:35:24.769 or it can be permanent. Can you imagine curing 00:35:24.769 --> 00:35:26.610 a child's heart failure but leaving them deaf 00:35:26.610 --> 00:35:28.849 because you were in a hurry with the IV push? 00:35:29.389 --> 00:35:32.429 That is a can't miss safety item, a huge one. 00:35:32.750 --> 00:35:35.260 And obviously... Lasix is famous for dumping 00:35:35.260 --> 00:35:38.239 potassium. Oh, yeah. So you are constantly monitoring 00:35:38.239 --> 00:35:40.860 for hypokalemia, watching for muscle weakness, 00:35:40.960 --> 00:35:44.159 cramping, and most dangerously, cardiac arrhythmias. 00:35:44.440 --> 00:35:47.239 And if that kid is also on digoxin, hypokalemia 00:35:47.239 --> 00:35:49.980 dramatically increases the risk of digoxin toxicity. 00:35:50.119 --> 00:35:53.159 It's a very dangerous cycle. OK, now let's contrast 00:35:53.159 --> 00:35:56.500 that with Lisinopril. Lisinopril is an ACE inhibitor. 00:35:56.579 --> 00:35:59.460 It works by stopping the conversion of angiotensin 00:35:59.460 --> 00:36:03.300 I, angiotensin II. Angiotensin II is a super 00:36:03.300 --> 00:36:05.599 potent vasoconstrictor. So by blocking it, the 00:36:05.599 --> 00:36:07.880 blood vessels dilate. We use it for afterload 00:36:07.880 --> 00:36:09.800 reduction. It makes it easier for the weak heart 00:36:09.800 --> 00:36:12.400 to pump against the body's resistance. But unlike 00:36:12.400 --> 00:36:14.880 Lasix, which dumps potassium, Lisinopril holds 00:36:14.880 --> 00:36:17.739 onto it. Right. ACE inhibitors are potassium 00:36:17.739 --> 00:36:19.579 sparing. So the electrolyte imbalance you're 00:36:19.579 --> 00:36:22.159 watching for here is hyperkalemia. You have to 00:36:22.159 --> 00:36:24.380 be really careful about giving potassium supplements 00:36:24.380 --> 00:36:26.579 to a child who's on Lisinopril. And here's a 00:36:26.579 --> 00:36:29.119 massive black box warning I'm seeing in the monograph 00:36:29.119 --> 00:36:32.849 for Lisinopril. fetal toxicity. This is huge. 00:36:33.030 --> 00:36:34.989 If you have an adolescent female patient with 00:36:34.989 --> 00:36:37.550 a cardiac condition who is on Lisinopril, you 00:36:37.550 --> 00:36:40.070 must be doing pregnancy screening and education. 00:36:40.409 --> 00:36:43.989 It's known to cause oligohydramnios, low amniotic 00:36:43.989 --> 00:36:47.289 fluid, fetal skull defects, and even fetal death. 00:36:47.530 --> 00:36:50.269 That is a critical patient education point for 00:36:50.269 --> 00:36:52.570 that specific demographic. I also saw a note 00:36:52.570 --> 00:36:54.730 in the source about compounding Lisinopril. Yes, 00:36:54.750 --> 00:36:57.409 this is a practical point. Lisinopril often only 00:36:57.409 --> 00:36:59.329 comes in tablets. You can't ask a six -month 00:36:59.329 --> 00:37:01.590 -old to swallow a pill, so the pharmacy will 00:37:01.590 --> 00:37:04.170 often have to make a liquid suspension. The source 00:37:04.170 --> 00:37:06.670 details an extemporaneous suspension crushing 00:37:06.670 --> 00:37:09.449 the tablets in simple syrup. The key for the 00:37:09.449 --> 00:37:11.630 nurse is to know that it needs to be shaken well 00:37:11.630 --> 00:37:14.730 before every dose and stored properly. Good to 00:37:14.730 --> 00:37:17.369 know. Okay, let's talk heparin. This one terrifies 00:37:17.369 --> 00:37:19.130 me because of the potential for concentration 00:37:19.130 --> 00:37:21.800 errors. It should. The source material highlights 00:37:21.800 --> 00:37:24.420 a long and tragic history of fatal errors with 00:37:24.420 --> 00:37:27.780 heparin in pediatrics. It comes in a catheter 00:37:27.780 --> 00:37:30.380 lock flush concentration, which is usually 10 00:37:30.380 --> 00:37:33.039 units per ml or 100 units per ml. That's just 00:37:33.039 --> 00:37:35.099 a tiny dose to keep an IV line from clotting. 00:37:35.280 --> 00:37:37.980 And then there is the hypotency injection, which 00:37:37.980 --> 00:37:41.119 can be a 1000, 5000, or even 10 ,000 units per 00:37:41.119 --> 00:37:44.320 ml. This is used for systemic anticoagulation 00:37:44.320 --> 00:37:46.780 for treating actual blood clots. And the vials 00:37:46.780 --> 00:37:49.909 can look very similar. They often do. Flushing 00:37:49.909 --> 00:37:52.409 those two concentrations has killed neonates. 00:37:53.030 --> 00:37:54.449 You think you're flushing a central line with 00:37:54.449 --> 00:37:56.809 10 units, but you accidentally give 10 ,000 units 00:37:56.809 --> 00:37:59.690 a thousand times the dose and cause a massive 00:37:59.690 --> 00:38:02.170 intracranial hemorrhage. Always, always, always 00:38:02.170 --> 00:38:04.190 double check the vial, read the label three times, 00:38:04.289 --> 00:38:06.630 have another nurse check it with you. And for 00:38:06.630 --> 00:38:09.869 monitoring a heparin drip? We monitor the APT, 00:38:10.530 --> 00:38:13.010 or activated partial thromboplastin time. That's 00:38:13.010 --> 00:38:15.329 the lab value we use to titrate the drip to a 00:38:15.329 --> 00:38:18.030 therapeutic level. And another key safety point, 00:38:18.530 --> 00:38:20.949 no IM injections for any child on Heparin. You 00:38:20.949 --> 00:38:24.389 will cause a massive painful hematoma. Got it. 00:38:24.889 --> 00:38:27.429 We mentioned propranolol for tet spells, but 00:38:27.429 --> 00:38:29.829 the source says it's also used for infantile 00:38:29.829 --> 00:38:33.210 hemangiomas. That seems random. It does, but 00:38:33.210 --> 00:38:36.179 it's very common now. A liquid formulation called 00:38:36.179 --> 00:38:39.159 hemangel is a first -line treatment for shrinking 00:38:39.159 --> 00:38:42.480 those benign vascular birthmarks. But the key 00:38:42.480 --> 00:38:44.519 safety pearl you need to know here is the risk 00:38:44.519 --> 00:38:48.059 of hypoglycemia. Really? A heart medication causing 00:38:48.059 --> 00:38:51.260 low blood sugar. Yes. Beta blockers can mask 00:38:51.260 --> 00:38:53.860 the early warning signs of hypoglycemia, like 00:38:53.860 --> 00:38:56.400 jitteriness or tachycardia, because they block 00:38:56.400 --> 00:38:58.920 the body's adrenaline response. They can also 00:38:58.920 --> 00:39:01.539 inhibit glycogenolysis, which is the body's ability 00:39:01.539 --> 00:39:03.840 to break down stored sugar from the liver. So 00:39:03.840 --> 00:39:05.960 if a baby isn't eating well and you give them 00:39:05.960 --> 00:39:08.760 propranolol? Their blood sugar can drop to dangerously 00:39:08.760 --> 00:39:11.360 low levels. So the hard and fast rule is you 00:39:11.360 --> 00:39:13.559 administer propranolol during or immediately 00:39:13.559 --> 00:39:15.980 after a feeding. You never give it if the child 00:39:15.980 --> 00:39:17.900 is vomiting or not taking their bottles well. 00:39:18.039 --> 00:39:20.440 That is a fantastic clinical pearl. What about 00:39:20.440 --> 00:39:23.239 hydrolazine? That's a direct acting vasodilator. 00:39:23.519 --> 00:39:25.780 It works right on the arteriolar smooth muscle 00:39:25.780 --> 00:39:28.019 to make it relax. The big side effect you have 00:39:28.019 --> 00:39:31.519 to watch for is reflex tachycardia. The body's 00:39:31.519 --> 00:39:33.679 fighting back. Exactly. The blood pressure drops 00:39:33.679 --> 00:39:36.059 because the vessels suddenly open up, so the 00:39:36.059 --> 00:39:38.679 heart speeds up to compensate and try to maintain 00:39:38.679 --> 00:39:41.440 cardiac output. It can defeat the purpose of 00:39:41.440 --> 00:39:43.780 the drug if you don't anticipate and manage it. 00:39:43.980 --> 00:39:46.139 And a weird administration quirk. The source 00:39:46.139 --> 00:39:48.460 notes that it can change color if it comes into 00:39:48.460 --> 00:39:50.739 contact with metal. That's a strange one, but 00:39:50.739 --> 00:39:52.780 good to know for drawing it up. You might need 00:39:52.780 --> 00:39:55.300 to use a filter needle or just be careful to 00:39:55.300 --> 00:39:58.139 avoid metal contact. And it also mentions a rare 00:39:58.139 --> 00:40:01.559 but serious lupus -like syndrome as a potential 00:40:01.559 --> 00:40:04.300 reaction with long -term use. Okay, let's move 00:40:04.300 --> 00:40:06.559 into our final section, Part E Synthesis. Let's 00:40:06.559 --> 00:40:08.940 connect all these dots. Mention the push -pull 00:40:08.940 --> 00:40:11.900 of potassium. Yes, this is a classic exam scenario. 00:40:12.019 --> 00:40:14.920 You have a child with heart failure who is on 00:40:14.920 --> 00:40:18.119 a regimen of digoxin, furosemide, lasix, and 00:40:18.119 --> 00:40:20.840 lisinopril. Furosemide makes you lose potassium, 00:40:21.199 --> 00:40:24.300 lisinopril makes you retain potassium, and digoxin 00:40:24.300 --> 00:40:27.239 toxicity is massively potentiated by low potassium. 00:40:27.400 --> 00:40:29.960 So the nurse is a tightrope walker. You are the 00:40:29.960 --> 00:40:32.610 tightrope walker. have to be monitoring the potassium 00:40:32.610 --> 00:40:34.949 levels constantly because tipping too far in 00:40:34.949 --> 00:40:37.250 either direction has a dangerous impact on the 00:40:37.250 --> 00:40:39.889 other drugs. If the K plus level gets too low 00:40:39.889 --> 00:40:43.570 from the Lasix, the Dagoxin can become toxic 00:40:43.570 --> 00:40:46.449 even at a normal dose. If the K plus level gets 00:40:46.449 --> 00:40:48.849 too high from the Lisinopril, you're at risk 00:40:48.849 --> 00:40:52.400 for fatal arrhythmias. Balance is absolutely 00:40:52.400 --> 00:40:54.599 everything. Exactly. You have to understand how 00:40:54.599 --> 00:40:57.239 all three drugs interact. And let's synthesize 00:40:57.239 --> 00:40:59.739 the opener versus closer one last time to really 00:40:59.739 --> 00:41:01.920 drive it home. Let's do it. You have a profoundly 00:41:01.920 --> 00:41:05.079 cyanotic newborn. You get an echo, and it shows 00:41:05.079 --> 00:41:08.860 TGA or tricuspid atresia. The plumbing is either 00:41:08.860 --> 00:41:11.460 crossed or completely blocked. You need mixing. 00:41:11.880 --> 00:41:14.219 You need that ductus arteriosus open. So you 00:41:14.219 --> 00:41:16.420 give alprostadil. You give alprostadil? Yeah. 00:41:16.679 --> 00:41:19.000 And you watch for apnea. You have a premature 00:41:19.000 --> 00:41:20.860 newborn who is struggling on the ventilator. 00:41:20.980 --> 00:41:24.219 They have wet, crackly lungs, a machinery -like 00:41:24.219 --> 00:41:27.199 murmur and bounding pulses. The duct is stuck 00:41:27.199 --> 00:41:29.679 open and it's flooding the lungs. You need it 00:41:29.679 --> 00:41:32.599 closed. You give endomethacin. You give endomethacin 00:41:32.599 --> 00:41:35.000 and you watch the urine output and look for any 00:41:35.000 --> 00:41:37.579 signs of gut bleeding. That is the 80 -20 right 00:41:37.579 --> 00:41:40.309 there. If you understand that one concept, you 00:41:40.309 --> 00:41:42.650 can answer a dozen different questions correctly 00:41:42.650 --> 00:41:45.030 and safely. Absolutely. And let's just revisit 00:41:45.030 --> 00:41:47.570 the heart failure regimen, the classic triad 00:41:47.570 --> 00:41:49.929 of medications. Right. It's often digoxin plus 00:41:49.929 --> 00:41:52.909 a diuretic, like Lasix, plus an ACE inhibitor, 00:41:53.050 --> 00:41:55.070 like Lisinopril. Think of it in terms of what 00:41:55.070 --> 00:41:57.969 each one does for the tired pump. One. Digoxin 00:41:57.969 --> 00:42:00.570 increases contractility. It makes the heart pump 00:42:00.570 --> 00:42:02.670 harder and more efficiently. We're improving 00:42:02.670 --> 00:42:06.170 the squeeze. The anotropy? Exactly. Two, Lasix 00:42:06.170 --> 00:42:09.010 removes excess fluid. It reduces preload. We're 00:42:09.010 --> 00:42:11.690 making the heart pump less volume, which reduces 00:42:11.690 --> 00:42:15.639 its workload. Three, the ACE inhibitor dilates 00:42:15.639 --> 00:42:18.559 the blood vessels. It reduces afterload. We're 00:42:18.559 --> 00:42:20.480 making it easier for the heart to pump against 00:42:20.480 --> 00:42:23.059 the resistance of the body. Harder squeeze, less 00:42:23.059 --> 00:42:25.179 volume, less resistance. It's all about improving 00:42:25.179 --> 00:42:27.539 efficiency. It's pure mechanics. The heart is 00:42:27.539 --> 00:42:29.639 a pump. We are just manipulating the variables 00:42:29.639 --> 00:42:32.260 to make the job easier for a tired, overworked 00:42:32.260 --> 00:42:34.079 muscle. As we start to wrap up, I want to look 00:42:34.079 --> 00:42:36.960 at the outro thought in our outline. We've mapped 00:42:36.960 --> 00:42:39.400 the plumbing, the inflammation, the consequences, 00:42:39.519 --> 00:42:42.099 and the chemical toolkit. But what about the 00:42:42.099 --> 00:42:44.599 long term? And that's the final provocative thought 00:42:44.599 --> 00:42:47.099 we want to leave you with. We call these surgical 00:42:47.099 --> 00:42:51.460 procedures repairs, not cures. That's a powerful 00:42:51.460 --> 00:42:54.960 distinction. It is. A child who has a tetralogy 00:42:54.960 --> 00:42:58.599 of phallate repair at six months old. What happens 00:42:58.599 --> 00:43:00.900 when they're 30? They don't just have a normal 00:43:00.900 --> 00:43:03.159 heart. They have scar tissue in their heart from 00:43:03.159 --> 00:43:05.380 the surgery. They might have a leaky pulmonary 00:43:05.380 --> 00:43:07.500 valve that will eventually need to be replaced. 00:43:08.000 --> 00:43:10.599 They are at a lifelong risk for arrhythmias because 00:43:10.599 --> 00:43:12.699 the electrical conduction tracks may have been 00:43:12.699 --> 00:43:14.880 cut during the initial surgery. And the Kawasaki 00:43:14.880 --> 00:43:17.260 kid. That kid who had Kawasaki at age three. 00:43:17.519 --> 00:43:20.119 They might have permanent coronary artery scarring, 00:43:20.159 --> 00:43:22.380 even if they didn't develop full -blown aneurysms. 00:43:22.639 --> 00:43:25.019 They need to monitor their cholesterol and their 00:43:25.019 --> 00:43:27.300 heart health much more aggressively as adults. 00:43:27.280 --> 00:43:30.800 because they have a pre -existing condition baked 00:43:30.800 --> 00:43:33.119 into their blood vessels. So pediatric cardiac 00:43:33.119 --> 00:43:35.320 nursing isn't just about saving the baby today. 00:43:35.659 --> 00:43:37.800 It's about setting the entire trajectory for 00:43:37.800 --> 00:43:40.159 the adult they will one day become. That's it, 00:43:40.340 --> 00:43:43.079 exactly. You are preserving precious heart muscle 00:43:43.079 --> 00:43:46.480 for a lifetime of use. Every prompt intervention 00:43:46.480 --> 00:43:49.219 you make, every correct medication dose you give, 00:43:49.679 --> 00:43:51.960 every time you catch a subtle sign of heart failure, 00:43:52.420 --> 00:43:54.619 you are preserving function not just for tomorrow, 00:43:54.760 --> 00:43:57.619 but for decades to come. That is a really powerful 00:43:57.619 --> 00:43:59.739 place to leave it. You've officially taken the 00:43:59.739 --> 00:44:01.699 deep dive into pediatric cardiac nursing. Now 00:44:01.699 --> 00:44:02.960 go save some tiny hearts.