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 --> 00:00:43.590 fast. Welcome to the emergency room. Welcome 00:00:43.590 --> 00:00:50.130 back to the Deep Dive. Today we are shifting 00:00:50.130 --> 00:00:52.600 gears a little bit. Just a little. Usually we 00:00:52.600 --> 00:00:54.780 explore topics for the sake of curiosity, and 00:00:54.780 --> 00:00:56.179 don't get me wrong, we are definitely going to 00:00:56.179 --> 00:00:58.799 satisfy some curiosity today, but we are framing 00:00:58.799 --> 00:01:02.140 this session differently. We're treating this 00:01:02.140 --> 00:01:05.519 as a high -yield, high -stakes exam prep session. 00:01:05.599 --> 00:01:07.760 That's right. We are putting on our clinical 00:01:07.760 --> 00:01:10.239 educator hats today. We aren't just talking about 00:01:10.239 --> 00:01:12.780 a disease in the abstract. We are talking about 00:01:12.780 --> 00:01:15.659 how to survive your pediatrics rotation and, 00:01:15.719 --> 00:01:18.620 more importantly, how to pass the NCLEX. without 00:01:18.620 --> 00:01:20.519 killing a hypothetical patient. The stakes are 00:01:20.519 --> 00:01:24.640 definitely higher. We have a massive stack of 00:01:24.640 --> 00:01:26.939 it here. We've got clinical care guides, some 00:01:26.939 --> 00:01:29.640 really technical pathogenesis papers, vaccination 00:01:29.640 --> 00:01:32.420 guidelines, and a whole bunch of nursing protocol 00:01:32.420 --> 00:01:35.760 sheets. And they are all focused on one specific 00:01:35.760 --> 00:01:38.920 itchy and surprisingly complex antagonist. Arachella. 00:01:39.540 --> 00:01:42.299 Better known to the world, of course, as Chickenpox. 00:01:42.799 --> 00:01:44.400 Exactly. And I know what you're probably thinking, 00:01:44.400 --> 00:01:47.620 because I thought it too. Chickenpox. Really? 00:01:47.680 --> 00:01:49.739 Isn't that just a mild rite of passage? You know, 00:01:49.760 --> 00:01:51.879 a few spots, some oatmeal baths, a week off. 00:01:51.879 --> 00:01:55.439 and you're done. And that is exactly the dangerous 00:01:55.439 --> 00:01:58.099 mindset we need to dismantle right now. If you 00:01:58.099 --> 00:02:00.359 go into your exams or your clinical rotations 00:02:00.359 --> 00:02:03.180 thinking Chickapox is just mild, you're gonna 00:02:03.180 --> 00:02:05.799 walk straight into a minefield. A minefield. 00:02:05.799 --> 00:02:09.240 That feels... Dramatic for a rash? It's not dramatic 00:02:09.240 --> 00:02:11.479 when you look at what exam writers focus on. 00:02:11.520 --> 00:02:13.419 It's not about the gitch. It's about the safety 00:02:13.419 --> 00:02:16.800 protocols. We are talking about strict isolation 00:02:16.800 --> 00:02:20.219 precautions, complex vaccine schedules with very 00:02:20.219 --> 00:02:23.639 specific contraindications. And this is the big 00:02:23.639 --> 00:02:27.729 one, fatal. Safety errors. Fatal. Yes. Specifically 00:02:27.729 --> 00:02:30.469 regarding medication that you can make if you 00:02:30.469 --> 00:02:32.849 aren't paying razor sharp attention. Fatal errors. 00:02:33.030 --> 00:02:34.849 Okay, that definitely grabbed my attention. So 00:02:34.849 --> 00:02:37.930 here is our mission for this deep dive. We are 00:02:37.930 --> 00:02:40.169 going to crack the code on varicella. I'm going 00:02:40.169 --> 00:02:42.370 to play the role of the student advocate here. 00:02:42.569 --> 00:02:44.590 I'm going to ask the confusing questions. I'm 00:02:44.590 --> 00:02:46.129 going to look for the shortcuts. And I'm going 00:02:46.129 --> 00:02:48.050 to try to figure out how to memorize all this 00:02:48.050 --> 00:02:51.229 stuff without my head exploding. And I will act 00:02:51.229 --> 00:02:53.750 as the clinical standard. Yeah. My job is to 00:02:53.750 --> 00:02:56.389 give you the rationale, the safety checks, and 00:02:56.389 --> 00:02:58.789 the why behind all the rules. Yeah. Because if 00:02:58.789 --> 00:03:00.930 you understand the why, you don't have to memorize 00:03:00.930 --> 00:03:04.789 nearly as much. Right. The rules stop being these. 00:03:05.000 --> 00:03:07.620 you know, random facts, and they start being 00:03:07.620 --> 00:03:10.099 logical consequences of the pathology. I love 00:03:10.099 --> 00:03:11.860 the sound of that. It's about connecting the 00:03:11.860 --> 00:03:14.740 dots, not just memorizing them. So give us the 00:03:14.740 --> 00:03:16.340 roadmap. Where are we starting? We are going 00:03:16.340 --> 00:03:18.680 to start with what I call the master 80 -20 map. 00:03:19.000 --> 00:03:22.500 The Pareto principle. Exactly. The 20 % you need 00:03:22.500 --> 00:03:25.460 to know to answer 80 % of the questions. We're 00:03:25.460 --> 00:03:27.840 going to look at varicella not just as a standalone 00:03:27.840 --> 00:03:30.680 disease, but as the prototype for the infectious 00:03:30.680 --> 00:03:33.939 rash pattern. If you mastered this one, You master 00:03:33.939 --> 00:03:36.620 a whole category of exam questions. Then we'll 00:03:36.620 --> 00:03:38.919 do a deep dive into the pathology, what the virus 00:03:38.919 --> 00:03:41.599 is actually doing inside the body. And finally, 00:03:41.740 --> 00:03:43.319 and this is the most important part for studying, 00:03:43.740 --> 00:03:45.780 we'll break down the need to know versus the 00:03:45.780 --> 00:03:48.340 nice to know. The need to know versus nice to 00:03:48.340 --> 00:03:50.460 know. That is my favorite category. OK, let's 00:03:50.460 --> 00:03:52.960 do it. Let's unpack this. Section A, the master 00:03:52.960 --> 00:03:56.340 80 -20 map. You mentioned using varicella as 00:03:56.340 --> 00:03:59.419 a prototype. Yes. In pediatrics, you're going 00:03:59.419 --> 00:04:04.360 to see a lot. of rashes. I mean, a lot. We call 00:04:04.360 --> 00:04:07.560 them viral exanthems. An exanthem. That's just 00:04:07.560 --> 00:04:09.500 a fancy word for a rash, right? It is. It's a 00:04:09.500 --> 00:04:11.500 widespread rash on the outside of the body. The 00:04:11.500 --> 00:04:14.460 baricella is like... the king of them for learning 00:04:14.460 --> 00:04:16.160 purposes, because it teaches you the fundamental 00:04:16.160 --> 00:04:18.819 rules of isolation that apply to a lot of other 00:04:18.819 --> 00:04:21.079 things. Okay, so when we're looking at this infectious 00:04:21.079 --> 00:04:23.560 rash pattern, what is the number one thing the 00:04:23.560 --> 00:04:26.019 exam writers, and honestly the real -life infection 00:04:26.019 --> 00:04:29.019 control nurses, are testing us on? It all comes 00:04:29.019 --> 00:04:31.680 down to decision points regarding isolation, 00:04:32.279 --> 00:04:34.579 specifically. When is this child contagious? 00:04:34.920 --> 00:04:36.720 This is the single most important public health 00:04:36.720 --> 00:04:38.759 question you have to answer. Everything else 00:04:38.759 --> 00:04:41.480 is secondary to that. And this is the classic 00:04:41.480 --> 00:04:43.740 return -to -school question, isn't it? The phone 00:04:43.740 --> 00:04:47.100 call every clinic gets. Mom calls, says little 00:04:47.100 --> 00:04:49.060 Timmy feels better. Can he go back to class tomorrow? 00:04:49.339 --> 00:04:52.000 It is. And here is the rule for varicella, and 00:04:52.000 --> 00:04:54.980 it is absolutely non -negotiable. The child is 00:04:54.980 --> 00:04:57.939 contagious from one to two days before the rash 00:04:57.939 --> 00:05:00.839 even appears. Which is... that's terrifying, 00:05:00.879 --> 00:05:02.879 by the way. They're walking around school, the 00:05:02.879 --> 00:05:05.199 grocery store, spreading it before anyone even 00:05:05.199 --> 00:05:07.769 knows they're sick. Exactly. That's the prodromal 00:05:07.769 --> 00:05:10.529 phase. They're shedding virus from their respiratory 00:05:10.529 --> 00:05:12.730 tract while they look perfectly healthy. But 00:05:12.730 --> 00:05:15.389 the exam question usually flips it. They ask, 00:05:15.709 --> 00:05:18.470 when does the contagiousness end? OK. So my first 00:05:18.470 --> 00:05:21.949 guess as a student would be when the fever breaks. 00:05:22.230 --> 00:05:24.790 That seems logical. A very logical guess. And 00:05:24.790 --> 00:05:26.829 that is the number one trap. The fever usually 00:05:26.829 --> 00:05:29.230 breaks days before the risk of transmission is 00:05:29.230 --> 00:05:32.250 gone. So that's wrong. OK. How about when the 00:05:32.250 --> 00:05:35.129 spots stop itching, when the child feels better? 00:05:36.000 --> 00:05:38.819 Also, no, comfort is not an indicator of safety 00:05:38.819 --> 00:05:41.660 here. They are contagious until, and I want you 00:05:41.660 --> 00:05:44.019 to burn this phrase into your brain, all lesions 00:05:44.019 --> 00:05:46.600 are crusted over. All lesions. Every single blister, 00:05:46.759 --> 00:05:49.339 not most of them, not the big ones, all of them 00:05:49.339 --> 00:05:52.000 need to be dry and scabby. Okay, all lesions 00:05:52.000 --> 00:05:54.660 crusted. I'm writing that down in big capital 00:05:54.660 --> 00:05:57.920 letters. So if a mom calls and says, Joey feels 00:05:57.920 --> 00:06:00.279 great, his fever is gone, but he still has three 00:06:00.279 --> 00:06:02.259 blisters on his back that are weeping a little 00:06:02.259 --> 00:06:05.220 bit, the answer is? He stays home. Yeah. He is 00:06:05.220 --> 00:06:07.839 a walking biohazard to anyone who isn't immune. 00:06:08.519 --> 00:06:11.139 If he goes to school, he exposes everyone. That 00:06:11.139 --> 00:06:13.639 clear fluid in those blisters, it's packed with 00:06:13.639 --> 00:06:16.300 live infectious virus. Right. OK. And that actually 00:06:16.300 --> 00:06:18.319 leads to the second key decision point you have 00:06:18.319 --> 00:06:21.459 to make, which is about differentiation. Differentiation 00:06:21.459 --> 00:06:24.160 between what? Between a vaccine reaction rash 00:06:24.160 --> 00:06:27.560 and the wild type breakthrough disease. Oh, right. 00:06:27.620 --> 00:06:29.939 Because sometimes the shot itself can cause a 00:06:29.939 --> 00:06:32.300 rash. It can. and we'll get into this more later, 00:06:32.660 --> 00:06:34.480 but you need to be able to look at a rash and 00:06:34.480 --> 00:06:37.019 make a clinical judgment. Is this the full -blown, 00:06:37.199 --> 00:06:39.839 highly contagious virus, or is this just a mild 00:06:39.839 --> 00:06:42.620 localized side effect of the shot? Because the 00:06:42.620 --> 00:06:44.939 isolation rules shift slightly based on that 00:06:44.939 --> 00:06:47.879 diagnosis. OK, that sounds like a tricky distinction 00:06:47.879 --> 00:06:49.959 to make, but let's talk about what we're actually 00:06:49.959 --> 00:06:52.420 looking for. What are the priority assessment 00:06:52.420 --> 00:06:56.079 cues? When I walk into the room, what am I seeing 00:06:56.079 --> 00:06:59.959 that screams varicella and not you know, measles 00:06:59.959 --> 00:07:02.459 or bug bites. You were looking for the crop progression. 00:07:02.779 --> 00:07:07.079 Crops? Like farming? In a way, yes. Think of 00:07:07.079 --> 00:07:10.120 it as waves of planting. Most rashes, like measles 00:07:10.120 --> 00:07:12.000 for example, they come out all at once. It starts 00:07:12.000 --> 00:07:14.339 at the head and it marches down the body. But 00:07:14.339 --> 00:07:16.740 it's a fairly uniform wave. Okay. Chickenpox, 00:07:17.060 --> 00:07:19.500 it comes in crops. You get a wave of spots today. 00:07:19.879 --> 00:07:21.639 Tomorrow you get a second wave. The next day 00:07:21.639 --> 00:07:23.639 you might get a third wave. So you have new spots 00:07:23.639 --> 00:07:25.800 and old spots happening at the same time, on 00:07:25.800 --> 00:07:28.350 the same kid. Precisely. And that leads to the 00:07:28.350 --> 00:07:30.230 hallmark medical term that you absolutely need 00:07:30.230 --> 00:07:33.730 to know for your exams, polymorphism. Polymorphism, 00:07:33.850 --> 00:07:36.189 okay, break that down. Poly means many, morph 00:07:36.189 --> 00:07:39.649 means form, many forms. Exactly. When you look 00:07:39.649 --> 00:07:42.170 at the child's trunk, you should see all stages 00:07:42.170 --> 00:07:44.670 of the rash present at the same time. You'll 00:07:44.670 --> 00:07:47.860 see a macropula. which is just a flat red spot 00:07:47.860 --> 00:07:50.300 right next to a vesicle, that's a fluid -celled 00:07:50.300 --> 00:07:52.839 blister, right next to a crust, which is a scab. 00:07:52.920 --> 00:07:56.720 OK. That classic image of a starry sky with all 00:07:56.720 --> 00:07:58.959 these different stages mixed together is the 00:07:58.959 --> 00:08:01.540 absolute signature of varitella zoster virus, 00:08:02.000 --> 00:08:05.379 VZV. That's a really helpful visual, a starry 00:08:05.379 --> 00:08:08.759 sky. So if I see a rash where every single spot 00:08:08.759 --> 00:08:10.720 looks exactly the same, they're all blisters 00:08:10.720 --> 00:08:13.259 or all scabs, I should probably be thinking about 00:08:13.259 --> 00:08:16.000 something else. Correct. Smallpox, for example, 00:08:16.060 --> 00:08:17.660 which I really hope you never see in your life, 00:08:17.660 --> 00:08:19.759 because that would be a global emergency, is 00:08:19.759 --> 00:08:22.459 monomorphic. One corm. Right. All the lesions 00:08:22.459 --> 00:08:25.120 are at the exact same stage of development. They 00:08:25.120 --> 00:08:27.980 progress together. Chickenpox is a chaotic, beautiful 00:08:27.980 --> 00:08:31.000 mix. OK. So I've identified it. I see the crops. 00:08:31.060 --> 00:08:33.120 I see the polymorphism. My brain is screaming, 00:08:33.500 --> 00:08:35.960 Vericella, what is my first line nursing action? 00:08:36.139 --> 00:08:38.740 What do I do immediately? Immediate isolation. 00:08:39.120 --> 00:08:40.980 And not just, hey, let's close the door isolation. 00:08:41.080 --> 00:08:43.440 We are talking airborne and contact precautions. 00:08:43.659 --> 00:08:49.860 Airborne means an N95 mask for me and a negative 00:08:49.860 --> 00:08:52.039 pressure room for the patient if possible. Yes, 00:08:52.159 --> 00:08:54.879 exactly. This virus is incredibly lightweight. 00:08:54.940 --> 00:08:56.840 It just floats on air currents. Yeah. If you 00:08:56.840 --> 00:08:58.620 just put them in a regular room with the door 00:08:58.620 --> 00:09:01.419 open, you are potentially exposing the entire 00:09:01.419 --> 00:09:04.860 hallway, the entire unit. Wow. And with that 00:09:04.860 --> 00:09:08.269 isolation, You need to be hyper aware of who 00:09:08.269 --> 00:09:11.909 is nearby. You must, must, must keep this patient 00:09:11.909 --> 00:09:14.389 away from immunocompromised individuals and pregnant 00:09:14.389 --> 00:09:16.029 women. We'll definitely touch on the pregnancy 00:09:16.029 --> 00:09:18.429 risk later, but that sounds like a major safety 00:09:18.429 --> 00:09:20.289 flag. It's one of the biggest. Yeah. And the 00:09:20.289 --> 00:09:22.250 second nursing action, which is tied to safety, 00:09:22.649 --> 00:09:24.929 is itch management. OK. And is that just for 00:09:24.929 --> 00:09:26.289 comfort? I mean, obviously, you don't want the 00:09:26.289 --> 00:09:28.230 kid to be miserable. Or is there a safety reason 00:09:28.230 --> 00:09:31.019 for that, too? It's both. The child is miserable, 00:09:31.340 --> 00:09:34.240 absolutely. The itch, the pruritus, is intense. 00:09:34.779 --> 00:09:36.659 But from a safety perspective, scratching leads 00:09:36.659 --> 00:09:38.759 to breaks in the skin, and breaks in the skin 00:09:38.759 --> 00:09:42.279 lead to secondary bacterial infection. Cephorias, 00:09:42.779 --> 00:09:45.639 group A strep. That is actually the number one 00:09:45.639 --> 00:09:47.500 reason children get hospitalized for chickenpox. 00:09:47.759 --> 00:09:49.700 It's not the virus itself. It's the bacteria 00:09:49.700 --> 00:09:51.759 that gets in afterwards. So stopping the itch 00:09:51.759 --> 00:09:54.299 is actually preventing sepsis. Exactly. You're 00:09:54.299 --> 00:09:56.139 not just giving calamine lotion for comfort. 00:09:56.379 --> 00:09:58.799 You're performing an infection control intervention. 00:09:59.019 --> 00:10:01.899 That's a huge reframe. OK, before we leave this 00:10:01.899 --> 00:10:06.080 80 -20 map. Give me the absolute can't miss safety 00:10:06.080 --> 00:10:08.799 items. The things that if I get wrong on an exam, 00:10:08.840 --> 00:10:11.779 I fail. Or if I get wrong in real life, I harm 00:10:11.779 --> 00:10:14.080 the patient. Two really big ones. Number one, 00:10:14.759 --> 00:10:17.340 the aspirin ban. No, aspirin. Got it. Absolute 00:10:17.340 --> 00:10:20.039 contraindication. You do not give salicylates, 00:10:20.100 --> 00:10:22.279 that's the chemical name for aspirin or aspirin 00:10:22.279 --> 00:10:24.779 containing products like Pepto -Bismol, to a 00:10:24.779 --> 00:10:27.500 child with a viral infection. Period. Because 00:10:27.500 --> 00:10:29.440 of Ray syndrome, I remember hearing about this 00:10:29.440 --> 00:10:32.440 in farm, but it feels a bit... Abstract, what 00:10:32.440 --> 00:10:35.100 actually happens in race syndrome? It's a metabolic 00:10:35.100 --> 00:10:38.120 disaster. The combination of the viral illness 00:10:38.120 --> 00:10:41.059 and the salicylates causes the mitochondria, 00:10:41.139 --> 00:10:43.559 the little powerhouses in the liver cells, to 00:10:43.559 --> 00:10:46.679 malfunction. So the liver suddenly stops being 00:10:46.679 --> 00:10:49.000 able to filter toxins, specifically ammonia. 00:10:49.220 --> 00:10:51.799 So ammonia just builds up in the blood. Yes, 00:10:52.279 --> 00:10:54.679 and ammonia is profoundly toxic to the brain. 00:10:55.120 --> 00:10:58.759 It causes acute cerebral edema. the brain swells. 00:10:59.039 --> 00:11:01.000 So you have a child who's recovering from a simple 00:11:01.000 --> 00:11:03.559 case of chicken pox, someone gives them aspirin 00:11:03.559 --> 00:11:05.919 for the fever, and suddenly they are vomiting 00:11:05.919 --> 00:11:07.799 uncontrollably, they're confused, and they're 00:11:07.799 --> 00:11:09.879 slipping into a coma due to acute liver failure 00:11:09.879 --> 00:11:12.720 and brain swelling. That is absolutely terrifying. 00:11:12.820 --> 00:11:15.759 So if the exam asks about figure management and 00:11:15.759 --> 00:11:18.120 one of the options is administer baby aspirin 00:11:18.120 --> 00:11:20.059 for comfort. You run away from that answer. You 00:11:20.059 --> 00:11:21.820 run fast. The correct answer is always going 00:11:21.820 --> 00:11:24.720 to be acetaminophen, Tylenol. Got it. Crystal 00:11:24.720 --> 00:11:27.669 clear. and the second safety item. Maternal timing. 00:11:28.029 --> 00:11:30.490 This is so specific. It's so important. If a 00:11:30.490 --> 00:11:33.230 mother develops the onset of her varicella rash 00:11:33.230 --> 00:11:35.230 in the window of five days before delivery to 00:11:35.230 --> 00:11:37.970 two days after delivery, that is a life -threatening 00:11:37.970 --> 00:11:40.289 emergency for the neonate. Five days before to 00:11:40.289 --> 00:11:43.769 two days after. Why that specific window? What's 00:11:43.769 --> 00:11:46.409 magical about those seven days? It's an immunological 00:11:46.409 --> 00:11:49.269 gap. It's a perfect storm. The mother gets infected 00:11:49.269 --> 00:11:51.710 and the virus enters her bloodstream. It crosses 00:11:51.710 --> 00:11:54.730 the placenta and infects the baby. But... And 00:11:54.730 --> 00:11:56.889 here's the key. The mother hasn't had enough 00:11:56.889 --> 00:11:59.549 time to produce her own protective Ig antibodies 00:11:59.549 --> 00:12:02.309 and pass them down to the baby. So the baby gets 00:12:02.309 --> 00:12:04.669 the full viral attack, but none of moms shield. 00:12:04.889 --> 00:12:07.730 Exactly. If the mom got sick, say three weeks 00:12:07.730 --> 00:12:09.690 before birth, she would have plenty of time to 00:12:09.690 --> 00:12:11.769 build up an antibody response and send those 00:12:11.769 --> 00:12:14.370 antibodies across the placenta. The baby would 00:12:14.370 --> 00:12:17.370 likely be born protected. But in that five day 00:12:17.370 --> 00:12:20.480 before, two day after window, The baby gets a 00:12:20.480 --> 00:12:23.440 massive viral load with absolutely zero maternal 00:12:23.440 --> 00:12:25.740 immune defense. It is a very, very high mortality 00:12:25.740 --> 00:12:28.139 rate. OK. That is definitely a need to know five 00:12:28.139 --> 00:12:29.980 days before, two days after delivery. Correct. 00:12:30.220 --> 00:12:32.379 So that's your map. That's your 80 -20. Isolate 00:12:32.379 --> 00:12:34.759 until crusted. Look for the polymorphous rash, 00:12:35.120 --> 00:12:37.639 no aspirin ever, and protect the neonate in that 00:12:37.639 --> 00:12:39.600 critical window. I feel like I could pass a quiz 00:12:39.600 --> 00:12:42.080 on that right now, but let's go deeper. Let's 00:12:42.080 --> 00:12:46.460 move into section B, the system by system cross 00:12:46.460 --> 00:12:49.399 -referenced lecture. Let's start with the absolute 00:12:49.399 --> 00:12:52.580 basics. Give me the one -liner identifier for 00:12:52.580 --> 00:12:55.779 varicella. Okay. Varicella is an acute infectious 00:12:55.779 --> 00:12:58.440 disease caused by the varicella zoster virus 00:12:58.440 --> 00:13:01.940 VZV. which is a member of the DNA herpesvirus 00:13:01.940 --> 00:13:06.100 family. It is characterized by generalized pruritic 00:13:06.100 --> 00:13:09.519 vesicular rash. Herpesvirus? That word always 00:13:09.519 --> 00:13:11.299 throws people off. They hear herpes and they 00:13:11.299 --> 00:13:13.779 think of something else entirely. It's a huge 00:13:13.779 --> 00:13:16.820 family of viruses. And the key trait of the herpes 00:13:16.820 --> 00:13:18.759 family, the thing they all have in common, is 00:13:18.759 --> 00:13:20.820 that they never really leave you. They stick 00:13:20.820 --> 00:13:23.600 around for life. They become latent. Which brings 00:13:23.600 --> 00:13:25.320 us right into the patho. How does this thing 00:13:25.320 --> 00:13:27.240 get in and where does it go? Let's do patho in 00:13:27.240 --> 00:13:29.779 plain language. Okay. The virus enters the body 00:13:29.779 --> 00:13:31.600 through the respiratory tract so you breathe 00:13:31.600 --> 00:13:34.259 it in or through the conjunctiva of the eyes. 00:13:34.500 --> 00:13:36.159 So you could breathe it in if someone coughs 00:13:36.159 --> 00:13:38.700 near you or you could like rub your eyes after 00:13:38.700 --> 00:13:41.840 touching a contaminated doorknob. Exactly. From 00:13:41.840 --> 00:13:44.200 there it sets up shop in the nasopharynx and 00:13:44.200 --> 00:13:46.519 the regional lymph nodes and it just starts replicating. 00:13:46.600 --> 00:13:48.580 It's making millions of copies of itself. This 00:13:48.580 --> 00:13:51.399 is the incubation period where you don't feel 00:13:51.399 --> 00:13:54.159 sick at all but the virus is multiplying like 00:13:54.159 --> 00:13:56.259 crazy. And then what happens? Then you get the 00:13:56.259 --> 00:13:58.659 viremia. That word just means virus in the blood. 00:13:59.559 --> 00:14:02.299 There are two phases. There's a primary viremia 00:14:02.299 --> 00:14:04.279 about four to six days after you're infected. 00:14:04.879 --> 00:14:07.019 This is when the virus spreads through the blood 00:14:07.019 --> 00:14:10.220 to the internal organs, like the liver, the spleen, 00:14:10.500 --> 00:14:12.860 and the sensory ganglia. Sensory ganglia. Those 00:14:12.860 --> 00:14:14.820 are the nerve bundles along the spine, right? 00:14:14.820 --> 00:14:18.059 Yes. And this is a key step. It's planting seeds 00:14:18.059 --> 00:14:20.720 in your nervous system for later. Then, after 00:14:20.720 --> 00:14:23.240 it's replicated in those organs, you get a secondary 00:14:23.240 --> 00:14:26.309 viremia. A much bigger wave of virus floods the 00:14:26.309 --> 00:14:28.509 bloodstream, and this time it hits the skin. 00:14:29.029 --> 00:14:30.690 And that's when you see the rash explode all 00:14:30.690 --> 00:14:32.610 over the body. So the rash is actually a late 00:14:32.610 --> 00:14:35.090 -stage event in the infection process. It is. 00:14:35.110 --> 00:14:37.950 It's the big, visible finale of the acute infection. 00:14:38.129 --> 00:14:40.610 And after the rash heals, you said it never leaves. 00:14:40.929 --> 00:14:43.980 It doesn't. After you recover... The virus goes 00:14:43.980 --> 00:14:46.240 into latency. It retreats from the skin and the 00:14:46.240 --> 00:14:49.059 blood, and it goes back into those sensory nerve 00:14:49.059 --> 00:14:51.820 ganglia, specifically the dorsal root ganglia 00:14:51.820 --> 00:14:54.179 that run along the spinal cord, and it goes to 00:14:54.179 --> 00:14:56.679 sleep. For how long? It can stay there dormant 00:14:56.679 --> 00:14:59.340 for decades. Yeah. But if your immune system 00:14:59.340 --> 00:15:02.240 weakens due to age, stress, or other illnesses 00:15:02.240 --> 00:15:05.519 later in life, that virus can wake up. And that's 00:15:05.519 --> 00:15:07.730 shingles. That is herpes zoster or shingles. 00:15:07.789 --> 00:15:10.289 It's the exact same virus just waking up from 00:15:10.289 --> 00:15:12.549 its nap. And because it was sleeping in a specific 00:15:12.549 --> 00:15:15.210 nerve root when it reactivates, it travels down 00:15:15.210 --> 00:15:17.870 the path of that one nerve to the skin. That's 00:15:17.870 --> 00:15:20.450 why shingles causes a rash in a dermatome, a 00:15:20.450 --> 00:15:22.590 specific strip of skin on one side of the body. 00:15:22.840 --> 00:15:26.299 That makes so much sense. That explains why shingles 00:15:26.299 --> 00:15:28.779 is usually just on one side of the body and doesn't 00:15:28.779 --> 00:15:30.980 cross the midline. It's literally following the 00:15:30.980 --> 00:15:33.299 roadmap of that one infected nerve. Precisely. 00:15:33.419 --> 00:15:35.879 It's a beautiful and painful demonstration of 00:15:35.879 --> 00:15:38.600 neuroanatomy. Let's talk about who gets this 00:15:38.600 --> 00:15:41.779 age -specific presentation. Does it look different 00:15:41.779 --> 00:15:44.580 in a baby versus a teen versus an adult? Oh, 00:15:44.580 --> 00:15:46.460 very different. It's like three different diseases. 00:15:46.899 --> 00:15:50.139 In children, it's usually considered mild. Often, 00:15:50.480 --> 00:15:53.279 the rash is the very first sign of illness. The 00:15:53.279 --> 00:15:56.600 prodrome is mild or completely absent. So a toddler 00:15:56.600 --> 00:15:58.460 could just be playing with blocks one minute, 00:15:58.480 --> 00:16:00.240 and the next minute mom is like, hey, what's 00:16:00.240 --> 00:16:03.000 that spot on your tummy? That's a classic scenario. 00:16:03.820 --> 00:16:05.940 Exactly. Their fever, if they even have one, 00:16:06.259 --> 00:16:08.899 and their malaise usually resolve in two to four 00:16:08.899 --> 00:16:12.799 days. But in adults, It is a much, much meaner 00:16:12.799 --> 00:16:15.220 beast. How so? Adults almost always have a distinct 00:16:15.220 --> 00:16:17.379 prodrome. They get one to two days of fever, 00:16:17.700 --> 00:16:20.019 headache, and feeling absolutely terrible before 00:16:20.019 --> 00:16:22.620 the rash ever appears. And they have much higher 00:16:22.620 --> 00:16:25.389 rates of serious complications. especially pneumonia. 00:16:25.669 --> 00:16:27.789 So if an adult gets chickenpox, we are worried 00:16:27.789 --> 00:16:30.769 about their lungs. Yes, viral varicella pneumonia 00:16:30.769 --> 00:16:33.730 in adults is a very serious concern. It presents 00:16:33.730 --> 00:16:36.389 with a nasty cough, chest pain, difficulty breathing, 00:16:36.649 --> 00:16:39.330 and it can progress rapidly to respiratory failure. 00:16:39.450 --> 00:16:41.769 And what about the third category? The vaccinated 00:16:41.769 --> 00:16:43.570 kids. I hear parents say this all the time. My 00:16:43.570 --> 00:16:45.429 kid got the shot, but they still got chickenpox. 00:16:45.529 --> 00:16:48.110 Is that a real thing? It is absolutely real, 00:16:48.210 --> 00:16:50.960 but we call it breakthrough varicella. And it 00:16:50.960 --> 00:16:53.340 presents very, very differently from the wild 00:16:53.340 --> 00:16:55.700 -type disease. It's much, much milder. Usually 00:16:55.700 --> 00:16:58.440 the child has fewer than 50 lesions total. And 00:16:58.440 --> 00:17:01.539 compare that to a normal case. How many lesions 00:17:01.539 --> 00:17:04.619 would an unvaccinated child get? A healthy unvaccinated 00:17:04.619 --> 00:17:07.759 child with wild -type chickenpox gets, on average, 00:17:08.200 --> 00:17:12.519 250 to 500 lesions. Whoa. So 50 versus 500. That 00:17:12.519 --> 00:17:14.740 is a massive difference. That's a huge difference. 00:17:14.779 --> 00:17:16.779 And in many of these breakthrough cases, the 00:17:16.779 --> 00:17:18.619 lesions don't even vesiculate. They don't form 00:17:18.619 --> 00:17:21.339 blisters. They just stay as maculopapular -like, 00:17:21.539 --> 00:17:23.920 just little red bumps. And often, there's no 00:17:23.920 --> 00:17:26.319 fever at all. That sounds incredibly tricky to 00:17:26.319 --> 00:17:28.319 diagnose, though. If it's just a few red bumps 00:17:28.319 --> 00:17:30.700 and no fever. That's the danger. It looks like 00:17:30.700 --> 00:17:32.819 bug bites. It looks like a mild allergic reaction. 00:17:33.380 --> 00:17:35.420 And if a nurse or a provider doesn't have a high 00:17:35.420 --> 00:17:37.819 index of suspicion and doesn't recognize it as 00:17:37.819 --> 00:17:39.880 breakthrough varicella, that child goes back 00:17:39.880 --> 00:17:42.039 to school or daycare. And because they're still 00:17:42.039 --> 00:17:44.200 contagious, they start an outbreak among the 00:17:44.200 --> 00:17:46.950 unvaccinated or immunocompromised. That is a 00:17:46.950 --> 00:17:49.470 really, really important point for both the exam 00:17:49.470 --> 00:17:52.349 and for real life. Breakthrough varicella looks 00:17:52.349 --> 00:17:55.190 like bug bites, but it's still contagious. Correct. 00:17:55.690 --> 00:17:58.329 Milder, but still a public health risk. OK, let's 00:17:58.329 --> 00:18:01.289 get into the heavy hitters. The need to know 00:18:01.289 --> 00:18:04.309 core content. We talked about the incubation 00:18:04.309 --> 00:18:06.809 period briefly. What are the numbers I need to 00:18:06.809 --> 00:18:09.150 have locked in? The standard incubation period 00:18:09.150 --> 00:18:12.930 is 14 to 16 days. But the full range is from 00:18:12.930 --> 00:18:15.650 10 to 21 days. So if a kid was at a birthday 00:18:15.650 --> 00:18:17.690 party with a cousin who broke out with spots 00:18:17.690 --> 00:18:20.049 the next day, the parents have to kind of hold 00:18:20.049 --> 00:18:22.609 their breath for up to three weeks? Basically, 00:18:22.809 --> 00:18:26.029 yes. Any time in that 10 to 21 day window, they 00:18:26.029 --> 00:18:28.430 can start showing symptoms. And the lesion description, 00:18:28.609 --> 00:18:30.289 you said vesicular. We talked about the different 00:18:30.289 --> 00:18:32.950 stages. What does that classic blister look like 00:18:32.950 --> 00:18:35.569 up close? The classic textbook description, which 00:18:35.569 --> 00:18:38.640 I always loved, is a ves - containing clear fluid 00:18:38.640 --> 00:18:41.140 on an erythematous base. It looks like a dew 00:18:41.140 --> 00:18:43.940 drop on a rose petal. That sounds oddly poetic 00:18:43.940 --> 00:18:46.440 for something so itchy and miserable. It does. 00:18:46.880 --> 00:18:48.839 But clinically, that's what you're looking for. 00:18:49.000 --> 00:18:52.299 A piney, fragile, clear, fluid -filled blister 00:18:52.299 --> 00:18:55.259 sitting on top of a red circle. And remember 00:18:55.259 --> 00:18:58.720 the distribution. Centripetal. Centripetal. Now 00:18:58.720 --> 00:19:01.299 my physics is rusty. Does that mean moving toward 00:19:01.299 --> 00:19:04.380 the center? Not quite. In this context, it means 00:19:04.380 --> 00:19:06.299 it is concentrated in the center of the body. 00:19:06.509 --> 00:19:09.529 The rash starts on the scalp, face, or trunk, 00:19:09.730 --> 00:19:12.190 and then moves outward to the extremities. So 00:19:12.190 --> 00:19:14.089 the highest number of spots will be on the chest, 00:19:14.230 --> 00:19:16.509 the back, and the stomach. The arms and legs 00:19:16.509 --> 00:19:19.029 will have fewer. That's a really good differentiator 00:19:19.029 --> 00:19:21.210 from something like hand, foot, and mouth disease, 00:19:21.289 --> 00:19:24.230 which loves the, well, the hands and face. Exactly. 00:19:24.569 --> 00:19:27.210 The distribution of the rash is a major diagnostic 00:19:27.210 --> 00:19:30.430 clue. Okay, now let's talk assessments. Priority 00:19:30.430 --> 00:19:32.910 nursing investments. I'm looking at this kid 00:19:32.910 --> 00:19:36.420 with a polymorphous centripetal rash. What am 00:19:36.420 --> 00:19:38.940 I checking first and why? Skin integrity is number 00:19:38.940 --> 00:19:41.720 one. You are constantly monitoring for redness, 00:19:41.940 --> 00:19:44.960 warmth, or purulent drainage pus that indicates 00:19:44.960 --> 00:19:47.319 a secondary bacterial infection. So I'm looking 00:19:47.319 --> 00:19:49.960 for a change in the lesion? Yes. If a blister 00:19:49.960 --> 00:19:52.220 stops looking like it has clear fluid and starts 00:19:52.220 --> 00:19:55.200 looking thick and yellow, or if the skin around 00:19:55.200 --> 00:19:57.740 one of the crusted lesions gets hot, swollen, 00:19:57.859 --> 00:20:01.099 and angry red, that's a huge red flag for staph 00:20:01.099 --> 00:20:03.049 or strep. And that's a point where it goes from 00:20:03.049 --> 00:20:05.589 a viral problem to a bacterial one. And that 00:20:05.589 --> 00:20:08.650 needs antibiotics. Chickenpox is viral, so we 00:20:08.650 --> 00:20:10.569 don't treat the pox itself with antibiotics, 00:20:11.029 --> 00:20:14.089 but we absolutely DO treat the secondary bacterial 00:20:14.089 --> 00:20:16.150 infection that piggybacks on it. Got it. Skin 00:20:16.150 --> 00:20:18.849 checks. What else is a priority? Neurological 00:20:18.849 --> 00:20:21.349 status. This is crucial and often overlooked. 00:20:21.430 --> 00:20:24.210 You need to watch for ataxia. Ataxia. That's 00:20:24.210 --> 00:20:26.309 a balance and coordination issue, right? Yes. 00:20:26.829 --> 00:20:28.569 The child might be walking like they're drunk, 00:20:29.089 --> 00:20:30.950 stumbling, unable to walk in a straight line. 00:20:31.069 --> 00:20:33.549 Or you might see changes in their level of consciousness, 00:20:33.849 --> 00:20:36.450 like confusion or extreme lethargy. This could 00:20:36.450 --> 00:20:39.589 indicate either cerebellar ataxia or, more seriously, 00:20:39.970 --> 00:20:42.809 encephalitis. Wait, chickenpox can actually infect 00:20:42.809 --> 00:20:46.849 the brain? It can. It's a complication. Cerebellar 00:20:46.849 --> 00:20:50.190 ataxia occurs in about 1 in 4 ,000 cases. It's 00:20:50.190 --> 00:20:52.700 an inflammation of the cerebellum. the part of 00:20:52.700 --> 00:20:54.920 the brain that controls balance. The child might 00:20:54.920 --> 00:20:57.500 get shaky or uncoordinated. The good news is 00:20:57.500 --> 00:20:59.440 it generally has a good outcome and resolves 00:20:59.440 --> 00:21:02.319 on its own over a few weeks. But encephalitis, 00:21:02.779 --> 00:21:05.779 that sounds much worse. Encephalitis is much 00:21:05.779 --> 00:21:09.500 rarer, about one in 50 ,000 cases, but it is 00:21:09.500 --> 00:21:12.019 much more dangerous. It's a direct inflammation 00:21:12.019 --> 00:21:14.759 of the brain tissue. It can cause seizures, coma, 00:21:14.980 --> 00:21:17.440 and permanent brain damage. So your neuro -assessment 00:21:17.440 --> 00:21:19.779 is not optional. You need to verify that the 00:21:19.779 --> 00:21:22.109 child is alert. oriented and moving normally. 00:21:22.849 --> 00:21:24.730 Okay. Skin checks for infection, neuro checks 00:21:24.730 --> 00:21:27.289 for ataxia and confusion. What about respiratory? 00:21:27.690 --> 00:21:30.190 Always. Especially in adults or in infants who 00:21:30.190 --> 00:21:32.230 get a bacterial super infection that spreads. 00:21:32.490 --> 00:21:34.430 You're watching for cough, increased work of 00:21:34.430 --> 00:21:36.549 breathing, or difficulty breathing. Listen to 00:21:36.549 --> 00:21:38.990 their lungs. Makes sense. Let's talk labs. If 00:21:38.990 --> 00:21:41.109 I'm in the clinic and we're not 100 % sure, how 00:21:41.109 --> 00:21:43.329 do we prove it's varicella? The gold standard 00:21:43.329 --> 00:21:46.200 for diagnosis is a PCR test. Polymerase chain 00:21:46.200 --> 00:21:48.440 reaction. It's the most sensitive and specific 00:21:48.440 --> 00:21:50.619 test we have. And what do you sample for that? 00:21:51.099 --> 00:21:54.660 Blood. No, you want the virus itself. You take 00:21:54.660 --> 00:21:58.119 a polyester swab and you gently unroof a fresh 00:21:58.119 --> 00:22:00.880 fluid -filled vesicle. You want to soak the swab 00:22:00.880 --> 00:22:04.460 in that vesicle fluid, or you can also vigorously 00:22:04.460 --> 00:22:07.259 swab a crusted lesion. Unroofing a vesicle sounds 00:22:07.259 --> 00:22:09.980 kind of painful. It's very quick, but it gives 00:22:09.980 --> 00:22:12.519 you the definitive yes or no answer. What about 00:22:12.519 --> 00:22:15.140 blood tests? I always see orders for IgM and 00:22:15.140 --> 00:22:18.119 IgG. So IgG is very useful to confirm immunity. 00:22:18.500 --> 00:22:20.400 If you want to know if a nurse is immune so she 00:22:20.400 --> 00:22:22.440 can safely care for the patient, you check her 00:22:22.440 --> 00:22:25.220 varicella Ig level. A positive result means she's 00:22:25.220 --> 00:22:28.279 immune. But for diagnosing an acute infection, 00:22:28.420 --> 00:22:30.819 don't bother ordering an IgM. Why not? It has 00:22:30.819 --> 00:22:32.559 too many false positives and false negatives. 00:22:32.700 --> 00:22:35.099 It just lacks the sensitivity and specificity 00:22:35.099 --> 00:22:38.119 you need for a reliable diagnosis. For diagnosis 00:22:38.119 --> 00:22:40.619 of an active case, you stick to the PCR of the 00:22:40.619 --> 00:22:43.019 lesion. PCR from the lesion is the gold standard. 00:22:43.240 --> 00:22:45.339 Got it. Okay. Priority interventions. We know 00:22:45.339 --> 00:22:48.700 isolation until all lesions are crusted. We know 00:22:48.700 --> 00:22:51.019 no aspirin. What else are we doing at the bedside 00:22:51.019 --> 00:22:53.779 for comfort and safety? Cool baths with baking 00:22:53.779 --> 00:22:57.279 soda or colloidal oatmeal are great for the itching. 00:22:57.740 --> 00:23:00.680 Calamine lotion can be soothing, but a huge one 00:23:00.680 --> 00:23:03.579 for parents is to keep the child's fingernails 00:23:03.579 --> 00:23:06.559 cut short. To prevent the scratching? To minimize 00:23:06.559 --> 00:23:08.759 the damage from scratching. For infants, you 00:23:08.759 --> 00:23:10.319 might even have to put little mittens on their 00:23:10.319 --> 00:23:13.119 hands. And then of course, hydration. Why is 00:23:13.119 --> 00:23:15.599 hydration such a big deal here? Because varicella 00:23:15.599 --> 00:23:18.019 doesn't just cause lesions on the skin. You can 00:23:18.019 --> 00:23:20.339 get them on mucous membranes, too. So kids can 00:23:20.339 --> 00:23:22.220 get painful sores in their mouths and throats. 00:23:22.400 --> 00:23:24.500 Oh, and if it hurts to swallow, they don't want 00:23:24.500 --> 00:23:27.259 to drink. Exactly. So they can get dehydrated 00:23:27.259 --> 00:23:30.319 very quickly. You have to be diligent about pushing 00:23:30.319 --> 00:23:33.339 fluids, popsicles, jello, whatever you can get 00:23:33.339 --> 00:23:35.700 into them. Let's loop back to parent education 00:23:35.700 --> 00:23:37.960 because that seems key here. We've told them 00:23:37.960 --> 00:23:41.509 no aspirin. What do we need to really drive home 00:23:41.509 --> 00:23:44.130 about scratching? You have to explain the why. 00:23:44.329 --> 00:23:46.630 It's not just don't scratch because I said so. 00:23:46.849 --> 00:23:49.269 It's we need you to help us prevent scratching 00:23:49.269 --> 00:23:51.589 because we don't want a serious staph infection 00:23:51.589 --> 00:23:54.109 that could put your child in the hospital on 00:23:54.109 --> 00:23:57.450 IV antibiotics. You have to connect their action 00:23:57.450 --> 00:24:01.029 to the serious potential consequence. Okay, I 00:24:01.029 --> 00:24:03.029 want to roleplay some exam writer favorites. 00:24:03.269 --> 00:24:05.509 These are the traps I know I'd fall into. Trap 00:24:05.509 --> 00:24:08.269 number one, can the child return to school once 00:24:08.269 --> 00:24:10.309 the fever breaks? We've hit this one hard, but 00:24:10.309 --> 00:24:13.829 I'll say it again, and no. The fever is irrelevant 00:24:13.829 --> 00:24:16.269 to contagiousness. The only thing that matters 00:24:16.269 --> 00:24:18.849 is when all lesions are crusted over. Okay, trap 00:24:18.849 --> 00:24:21.410 number two, the child was exposed to their cousin 00:24:21.410 --> 00:24:24.200 with chicken pox three days ago. Is it too late 00:24:24.200 --> 00:24:26.740 to do anything like vaccinate them? This is a 00:24:26.740 --> 00:24:29.279 fantastic question and a very high level clinical 00:24:29.279 --> 00:24:32.440 point. The answer is NO. It is not too late. 00:24:32.589 --> 00:24:35.170 Post exposure prophylaxis with the varicella 00:24:35.170 --> 00:24:38.970 vaccine is 70 to 100 % effective at preventing 00:24:38.970 --> 00:24:41.690 or significantly modifying the disease if it's 00:24:41.690 --> 00:24:43.430 given within three to five days of exposure. 00:24:43.630 --> 00:24:45.829 Wow. So even after they've already breathed in 00:24:45.829 --> 00:24:47.589 the virus, if you give the vaccine quick enough, 00:24:47.710 --> 00:24:49.549 you can stop the infection from taking hold. 00:24:49.829 --> 00:24:52.950 Or at the very least, you can turn a 500 lesion 00:24:52.950 --> 00:24:56.509 high fever case into a 20 lesion no fever breakthrough 00:24:56.509 --> 00:24:59.410 case. So if a sibling brings it home from school, 00:24:59.930 --> 00:25:02.170 you run the other unvaccinated sibling to the 00:25:02.170 --> 00:25:05.809 clinic immediately that day. That is a huge clinical 00:25:05.809 --> 00:25:07.890 pearl. Post -exposure vaccination works within 00:25:07.890 --> 00:25:09.250 three to five days. I'm definitely remembering 00:25:09.250 --> 00:25:11.470 that one. You should. OK. Trap number three. 00:25:11.930 --> 00:25:14.450 The doctor prescribed amoxicillin for the child's 00:25:14.450 --> 00:25:16.390 chicken pox. What's wrong with that picture? 00:25:16.630 --> 00:25:19.609 It's a trap. Unless there is clear documentation 00:25:19.609 --> 00:25:22.029 of a secondary bacterial infection, you know, 00:25:22.170 --> 00:25:25.269 pus, warmth, cellulitis, or returning fever antibiotics 00:25:25.269 --> 00:25:28.170 are the wrong choice, it's a virus. Moxacillin 00:25:28.170 --> 00:25:30.890 does nothing for VZV. Right, it's treating the 00:25:30.890 --> 00:25:33.109 wrong bug. Okay, let's shift gears slightly. 00:25:33.549 --> 00:25:36.569 Moving on to section five, development and milestones. 00:25:37.109 --> 00:25:39.569 How does a disease like this mess with the child's 00:25:39.569 --> 00:25:42.109 long -term development? Well, physically, other 00:25:42.109 --> 00:25:44.230 than the potential for scarring, The biggest 00:25:44.230 --> 00:25:46.089 developmental hit comes from something called 00:25:46.089 --> 00:25:48.490 congenital varicella syndrome. This is what happens 00:25:48.490 --> 00:25:50.369 if a mom gets infected in the first 20 weeks 00:25:50.369 --> 00:25:52.349 of pregnancy. The first half of the pregnancy? 00:25:52.710 --> 00:25:55.809 Yes. The virus is teratogenic during that period. 00:25:56.450 --> 00:25:58.910 It attacks the developing fetus. It can cause 00:25:58.910 --> 00:26:01.369 limb hycoplasia, meaning underdeveloped or missing 00:26:01.369 --> 00:26:04.829 arms or legs. Microcephaly, a small head and 00:26:04.829 --> 00:26:07.509 brain. Skin scarring in a dermatomal pattern. 00:26:08.170 --> 00:26:11.109 Eye problems. It's absolutely devastating. That's 00:26:11.109 --> 00:26:13.569 heartbreaking. So prenatal screening for varicella 00:26:13.569 --> 00:26:16.009 immunity is vital for women of childbearing age. 00:26:16.150 --> 00:26:18.710 It is an absolute must. Women should be screened 00:26:18.710 --> 00:26:20.630 for immunity before they even try to get pregnant 00:26:20.630 --> 00:26:23.630 and vaccinated if they're not immune. What about 00:26:23.630 --> 00:26:26.390 the social and educational impact for a regular 00:26:26.390 --> 00:26:29.009 school -aged kid who gets it? The isolation is 00:26:29.009 --> 00:26:31.069 hard. A week or two out of school is a long time 00:26:31.069 --> 00:26:33.660 for a child. It's social disconnection. They 00:26:33.660 --> 00:26:35.160 miss their friends. They miss their routine. 00:26:35.579 --> 00:26:38.339 So key nursing action is to encourage play and 00:26:38.339 --> 00:26:40.880 normalcy, even if they're in isolation in a hospital 00:26:40.880 --> 00:26:43.900 room. Bring in child life specialists. Find activities 00:26:43.900 --> 00:26:45.720 they can do. Don't just leave them behind a closed 00:26:45.720 --> 00:26:48.019 door with an iPad. And for that very specific 00:26:48.019 --> 00:26:51.440 case we mentioned earlier, the neonate born to 00:26:51.440 --> 00:26:53.980 the sick mom. Right. The five days before two 00:26:53.980 --> 00:26:57.049 days after window. If that happens, that baby 00:26:57.049 --> 00:26:59.690 is in critical danger. They need an injection 00:26:59.690 --> 00:27:02.049 of something called Verizig immediately after 00:27:02.049 --> 00:27:05.029 birth. Verizig? What is that? It's hand for varicella 00:27:05.029 --> 00:27:07.789 zoster immune globulin. It's basically a shot 00:27:07.789 --> 00:27:09.990 full of pre -made antibodies against the chicken 00:27:09.990 --> 00:27:12.990 pox virus. It's passive immunity. We are giving 00:27:12.990 --> 00:27:15.049 the baby the antibodies that the mom didn't have 00:27:15.049 --> 00:27:17.630 time to make and pass along. It is a literal 00:27:17.630 --> 00:27:20.269 lifesaver. Okay, let's pivot to the vaccine itself. 00:27:20.730 --> 00:27:23.299 Section 6. I feel like vaccines are a whole exam 00:27:23.299 --> 00:27:25.539 topic on their own. They are. You absolutely 00:27:25.539 --> 00:27:27.460 have to know the vaccine specifics. You need 00:27:27.460 --> 00:27:30.339 to know the types. There's VAR, which is sold 00:27:30.339 --> 00:27:32.640 as Varivax, and it's just the chicken pox vaccine 00:27:32.640 --> 00:27:36.180 by itself. And then there's MMRV, sold as ProQuad, 00:27:36.319 --> 00:27:39.119 which is measles, mumps, rubella, and varicella 00:27:39.119 --> 00:27:41.640 all combined into one shot. And both of these 00:27:41.640 --> 00:27:44.940 are live attenuated vaccines. Yes. That is a 00:27:44.940 --> 00:27:47.420 critical point. That means they contain a weakened 00:27:47.420 --> 00:27:50.259 but still live version of the virus. This is 00:27:50.259 --> 00:27:52.299 very important when we talk about contraindications. 00:27:52.539 --> 00:27:54.640 OK, so what's the standard schedule? Dose one 00:27:54.640 --> 00:27:57.880 is given between 12 and 15 months of age. Dose 00:27:57.880 --> 00:28:00.079 two is given between four and six years of age, 00:28:00.420 --> 00:28:02.019 usually right before they start kindergarten. 00:28:02.220 --> 00:28:04.359 So it's basically on the same schedule as the 00:28:04.359 --> 00:28:07.140 MMR vaccine. Exactly. which is why the combo 00:28:07.140 --> 00:28:09.519 shot exists. Now here is a very specific detail 00:28:09.519 --> 00:28:11.539 I saw in the notes and it feels like a perfect 00:28:11.539 --> 00:28:14.740 exam question. There's a warning about febrile 00:28:14.740 --> 00:28:17.960 seizures with the MMRV combo shot. This is a 00:28:17.960 --> 00:28:20.759 high level exam detail but a great one. The data 00:28:20.759 --> 00:28:22.980 shows that the risk of febrile seizures is two 00:28:22.980 --> 00:28:25.980 times higher if you give the combined MMRV shot 00:28:25.980 --> 00:28:29.240 as the first dose to toddlers between 12 and 00:28:29.240 --> 00:28:32.559 23 months compared to giving separate MMR and 00:28:32.559 --> 00:28:35.339 VAR shots at the same visit. Wait, really? So 00:28:35.339 --> 00:28:37.900 combining them into one shot for that first dose 00:28:37.900 --> 00:28:40.240 actually increases the seizure risk? Slightly, 00:28:40.400 --> 00:28:42.940 yes. The absolute risk is still very low, but 00:28:42.940 --> 00:28:45.420 the relative risk is doubled. So the current 00:28:45.420 --> 00:28:47.880 clinical preference and exam tip is that separate 00:28:47.880 --> 00:28:50.829 vaccines are preferred for dose one. one. MMRV 00:28:50.829 --> 00:28:52.769 is fine, and even preferred for convenience, 00:28:53.109 --> 00:28:55.970 for dose two at age four to six. That's fascinating. 00:28:56.130 --> 00:28:57.769 So for the one -year -old, it's better to poke 00:28:57.769 --> 00:28:59.609 them twice. For the five -year -old, it's fine 00:28:59.609 --> 00:29:01.670 to poke them once with the combo. Precisely. 00:29:01.789 --> 00:29:04.289 Let's talk contraindications. Since it's a live 00:29:04.289 --> 00:29:06.829 vaccine, who absolutely cannot get this shot? 00:29:07.210 --> 00:29:09.990 OK, first, anyone with a history of a severe 00:29:09.990 --> 00:29:13.319 allergic reaction? like anaphylaxis, to gelatin 00:29:13.319 --> 00:29:16.740 or to the antibiotic neomycin. Gelatin and neomycin. 00:29:16.920 --> 00:29:18.680 Okay, need to memorize those two components. 00:29:18.920 --> 00:29:23.119 Yes. And because it is a live virus. Pregnancy. 00:29:23.420 --> 00:29:25.359 Pregnant women cannot get the varicella vaccine 00:29:25.359 --> 00:29:27.900 because of the theoretical risk to the fetus. 00:29:28.039 --> 00:29:29.980 And if a woman gets the shot, how long should 00:29:29.980 --> 00:29:32.059 she wait before trying to get pregnant? She should 00:29:32.059 --> 00:29:34.420 avoid pregnancy for one month after the shot. 00:29:34.559 --> 00:29:37.079 Got it. Who else is on the no list? Anyone with 00:29:37.079 --> 00:29:39.700 severe immunosuppression. So kids with certain 00:29:39.700 --> 00:29:42.599 cancers like leukemia or lymphoma, or kids with 00:29:42.599 --> 00:29:45.819 HIV who have very low CD4 counts, their immune 00:29:45.819 --> 00:29:48.259 systems are too weak to handle even the weakened 00:29:48.259 --> 00:29:50.940 vaccine virus, it could cause a disseminated 00:29:50.940 --> 00:29:53.000 infection. And what about someone who just got 00:29:53.000 --> 00:29:56.480 blood products, like if a child received IVIG 00:29:56.480 --> 00:29:59.819 for Kawasaki disease? Great question. You have 00:29:59.819 --> 00:30:02.799 to wait. If they recently received antibodies, 00:30:03.180 --> 00:30:05.660 either from a blood transfusion or from IVE, 00:30:06.059 --> 00:30:08.660 those antibodies will just kill the vaccine virus 00:30:08.660 --> 00:30:10.779 before the child's own body has a chance to learn 00:30:10.779 --> 00:30:12.640 from it and build its own immunity. You have 00:30:12.640 --> 00:30:15.220 to wait anywhere from three to 11 months, depending 00:30:15.220 --> 00:30:18.039 on the product they received. That is such a 00:30:18.039 --> 00:30:21.019 tricky scheduling question for an exam. A child 00:30:21.019 --> 00:30:23.859 received IVIG for Kawasaki disease two months 00:30:23.859 --> 00:30:26.680 ago. Is it appropriate to administer the varicella 00:30:26.680 --> 00:30:29.539 vaccine today? And the answer is no. Correct. 00:30:29.680 --> 00:30:31.500 You have to delay it. Okay, let's do a quick 00:30:31.500 --> 00:30:34.420 nice -to -know pass, Section 7. These are the 00:30:34.420 --> 00:30:36.779 interesting tidbits that add context but maybe 00:30:36.779 --> 00:30:38.940 aren't on every test. What's some history here? 00:30:39.119 --> 00:30:40.859 Well, for centuries, it wasn't distinguished 00:30:40.859 --> 00:30:43.359 from smallpox. People just thought it was a milder 00:30:43.359 --> 00:30:45.640 form of the same disease. It wasn't until the 00:30:45.640 --> 00:30:47.819 late 19th century that doctors figured out there 00:30:47.819 --> 00:30:50.220 were two totally different viruses. Can you imagine 00:30:50.220 --> 00:30:53.140 confusing the two? I mean, they're both pox viruses 00:30:53.140 --> 00:30:55.259 that cause blisters. I can see who they would. 00:30:55.440 --> 00:30:58.480 True. But smallpox is deadly on a completely 00:30:58.480 --> 00:31:01.119 different scale. The vaccine we use today was 00:31:01.119 --> 00:31:03.940 actually developed in Japan in the 1970s. What 00:31:03.940 --> 00:31:06.059 about environmental survival? How long does it 00:31:06.059 --> 00:31:08.779 live on a countertop? The virus is actually pretty 00:31:08.779 --> 00:31:11.299 wimpy outside the body. It has a short survival 00:31:11.299 --> 00:31:13.900 time on surfaces. It's not like norovirus that 00:31:13.900 --> 00:31:16.480 can live for weeks. It really needs a human host 00:31:16.480 --> 00:31:19.319 to survive and spread effectively. And the shingles 00:31:19.319 --> 00:31:22.039 connection. Let's clear this up once and for 00:31:22.039 --> 00:31:24.240 all. Can I catch shingles from you if you have 00:31:24.240 --> 00:31:27.380 shingles? No. You absolutely cannot catch shingles 00:31:27.380 --> 00:31:30.299 from someone. Shingles is a reactivation of your 00:31:30.299 --> 00:31:33.619 own latent virus that's already inside you from 00:31:33.619 --> 00:31:37.140 when you had chickenpox, B -U -T. There's a butt. 00:31:37.359 --> 00:31:39.799 There's a big butt. If I have an active shingles 00:31:39.799 --> 00:31:42.980 rash with weeping blisters and you have never 00:31:42.980 --> 00:31:46.420 had chickenpox and are not vaccinated, you can 00:31:46.420 --> 00:31:48.960 catch chickenpox from my shingles lesions. That's 00:31:48.960 --> 00:31:51.559 the classic mix -up. Grandma has a shingles outbreak. 00:31:51.740 --> 00:31:53.660 She comes to visit the new baby. The baby doesn't 00:31:53.660 --> 00:31:56.819 get shingles. The baby gets shingled pain. Because 00:31:56.819 --> 00:31:59.579 the virus in her shingles blister is VZV, and 00:31:59.579 --> 00:32:02.000 to a nonimmune person, that primary infection 00:32:02.000 --> 00:32:04.960 will manifest as varicella or chickenpox. Okay, 00:32:05.359 --> 00:32:07.660 section C, cross -linking consensus. We touched 00:32:07.660 --> 00:32:10.359 on smallpox. Let's clarify the key difference 00:32:10.359 --> 00:32:12.819 in the lesions one more time. Smallpox lesions 00:32:12.819 --> 00:32:14.900 are monomorphic. They all develop at the same 00:32:14.900 --> 00:32:16.799 pace. They're all vesicles at the same time, 00:32:16.980 --> 00:32:19.779 then all pustules, then all scabs. They're also 00:32:19.779 --> 00:32:24.250 deep, hard, and well circumscribed. Fertile lesions 00:32:24.250 --> 00:32:26.950 are polymorphic. They're in all stages at once, 00:32:27.170 --> 00:32:30.190 the starry sky. And they're superficial, delicate, 00:32:30.190 --> 00:32:33.529 and they come in crops. And bacterial super infection 00:32:33.529 --> 00:32:36.390 versus normal progression. How do I tell the 00:32:36.390 --> 00:32:38.579 difference at a glance? Normal progression is 00:32:38.579 --> 00:32:40.680 clear fluid, then it gets a little cloudy, then 00:32:40.680 --> 00:32:42.839 it crusts over. The fever should be gone after 00:32:42.839 --> 00:32:45.259 the first few days. Bacterial super infection 00:32:45.259 --> 00:32:47.480 is when the fluid turns into thick honey -colored 00:32:47.480 --> 00:32:50.140 or yellow pus. The redness around the lesion 00:32:50.140 --> 00:32:52.220 starts to spread and gets hot and tender, that's 00:32:52.220 --> 00:32:54.539 cellulitis. And the biggest red flag of all is 00:32:54.539 --> 00:32:56.720 the return of a high fever. The return of fever 00:32:56.720 --> 00:32:59.740 is a huge red flag. A massive red flag. If a 00:32:59.740 --> 00:33:01.740 kid is getting better, feeling good, and then 00:33:01.740 --> 00:33:04.140 on day five or six they suddenly spike a fever 00:33:04.140 --> 00:33:07.500 of 103, You have to assume a bacterial super 00:33:07.500 --> 00:33:09.779 infection until proven otherwise. And looking 00:33:09.779 --> 00:33:11.940 at our source materials, they all agree on the 00:33:11.940 --> 00:33:14.640 strict isolation until crusting and the absolute 00:33:14.640 --> 00:33:17.859 aspirin ban. Yes, those are the non -negotiable 00:33:17.859 --> 00:33:20.420 pillars of safe care for varicella. OK, wow, 00:33:20.579 --> 00:33:22.980 we have covered a massive amount of ground. Let's 00:33:22.980 --> 00:33:25.500 try to summarize this into a safe, usable package 00:33:25.500 --> 00:33:27.680 for someone walking onto the floor or into an 00:33:27.680 --> 00:33:30.759 exam. What are the top takeaways? Takeaway number 00:33:30.759 --> 00:33:33.789 one is all about safety. No aspirin because of 00:33:33.789 --> 00:33:36.450 ray syndrome. Check pregnancy and immune status 00:33:36.450 --> 00:33:39.549 before giving a live vaccine. And strict airborne 00:33:39.549 --> 00:33:42.910 and contact isolation until every single lesion 00:33:42.910 --> 00:33:45.829 is crusted over. Got it. Takeaway two. Assessment. 00:33:46.930 --> 00:33:48.930 Look for the polymorphous rash, the crops of 00:33:48.930 --> 00:33:51.390 different stages. Look for the centripetal spread 00:33:51.390 --> 00:33:54.650 concentrated on the trunk. And always, always 00:33:54.650 --> 00:33:57.329 watch for neurological changes, especially ataxia. 00:33:57.670 --> 00:33:59.890 And takeaway number three. Intervention. Stop 00:33:59.890 --> 00:34:02.250 the itch to prevent secondary bacterial infection. 00:34:02.569 --> 00:34:05.049 Push fluids to prevent dehydration. And remember, 00:34:05.089 --> 00:34:08.369 you can use the vaccine as post -exposure prophylaxis 00:34:08.369 --> 00:34:10.670 if you give it within three to five days of exposure. 00:34:11.170 --> 00:34:13.250 And here is a final provocative thought for you 00:34:13.250 --> 00:34:16.090 to chew on as you study. We talked about breakthrough 00:34:16.090 --> 00:34:19.090 varicella. As vaccination rates continue to rise, 00:34:19.550 --> 00:34:23.269 the classic miserable 500 -lesion chicken pox 00:34:23.269 --> 00:34:26.730 case is disappearing. We are seeing more and 00:34:26.730 --> 00:34:31.030 more of these modified 50 -lesion, non -blistering 00:34:31.030 --> 00:34:33.349 rashes. Which raises a really important question 00:34:33.349 --> 00:34:35.349 for the next generation of nurses and doctors. 00:34:36.050 --> 00:34:38.880 Will you recognize it? If a child comes into 00:34:38.880 --> 00:34:42.059 the ER in January with 15 red bumps on their 00:34:42.059 --> 00:34:44.280 stomach that look like mosquito bites, will you 00:34:44.280 --> 00:34:47.460 have the index of suspicion to ask about vaccination 00:34:47.460 --> 00:34:50.000 status and recent exposures? Or will you just 00:34:50.000 --> 00:34:51.579 dismiss it as bug bites and send them back to 00:34:51.579 --> 00:34:53.599 the waiting room? Exactly. Send them back to 00:34:53.599 --> 00:34:56.219 the waiting room to infect the immunocompromised 00:34:56.219 --> 00:34:58.199 kid getting chemo who is sitting next to them. 00:34:58.860 --> 00:35:01.079 The disease is changing its face because of our 00:35:01.079 --> 00:35:03.619 success with vaccines. And that means we have 00:35:03.619 --> 00:35:05.440 to be smarter and more vigilant to catch it. 00:35:05.559 --> 00:35:07.909 That is the challenge. Memorize the old textbook 00:35:07.909 --> 00:35:10.550 picture. Precisely. Look at the patient in front 00:35:10.550 --> 00:35:13.070 of you, consider the context, and always think 00:35:13.070 --> 00:35:15.409 about public health. Take these notes, re -listen 00:35:15.409 --> 00:35:18.150 to the isolation rules, and go crush that exam. 00:35:18.210 --> 00:35:20.670 You've got this. Stay curious and wash your hands. 00:35:21.050 --> 00:35:22.510 See you in the next deep dive.