How to WORK-UP and treat HYDROPS // what are outcomes like?!

Hello, welcome to Tala Talks NICU. I am Dr. Tala, and on this channel, we break down medical neonatal concepts and make them super easy for you to understand. On this video, we are going to be talking about hydrops. So I would highly recommend that you go back and watch the first video on hydrops, where we talked about what it actually is, we described it, and what is the etiology of it, like how is hydrops caused, and some general differential diagnoses that are associated with hydrops. So this is part two of the hydrops video, and today we're gonna be talking about the workup of hydrops, so what you do when you find out that a baby does have hydrops. Number two, we're going to talk about the treatment of hydrops, and number three, we're going to talk about the outcomes after infants are diagnosed with hydrops. Before we continue, I'm going to ask you to like this video and to subscribe to this channel if you're just interested in neonatal concepts. We absolutely love building this community, and we really love hearing from you all. So let's start with part one, how do you work up hydrops? So a huge caveat here is that very often this is a kind of OB realm, because if you think about it, most babies are known to be hydropic now in utero because prenatal testing has gotten so good, prenatal ultrasounds have gotten so good. Maybe the obstetrician saw the hydrops, so saw buildup of fluid in more than one compartment or two compartments or more on just a routine ultrasound. Maybe the mummy was measuring very large for dates, because as we talked about in the first video, a lot of these babies can also have polyhydramnios, or maybe even the mother presented with mirror syndrome, which is basically where the mother is mirroring what's happening with the fetus in utero. So as the baby's getting more and more swollen, the mother gets more and more swollen and edematous. Obviously, I'm not an obstetrician, so I'm not gonna go over the details of how the diagnosis of the pericardial effusion or the ascites or anything is made. What I'm going to talk about is kind of the overall process that we use in the diagnosis of a baby that was found to have hydrops. Obviously, if a baby is born and wasn't diagnosed with hydrops prenatally, then we'll follow a pretty similar algorithm after the baby is born. So if you watched the last video, you'll remember kind of the big categories of diseases that cause hydrops. So obviously, and very logically, when we're trying to figure out what caused the hydrops, we have to make sure that we cover all those diseases. As we talked about in the first video, one of the first biggest differentiating steps that you have to make is figure out whether this is immune hydrops or non-immune hydrops, and I'll get back to that in a second. If it is non-immune hydrops, then you can follow the algorithm that was recommended by the Society for Fetal Maternal Medicine, or SMFM, that was written up in 2015. But obviously, before we even go down the pathway of non-immune hydrops, we have to be very certain that this is not immune hydrops. So the mother's blood type has to be tested, and the presence of any circulating antibodies, which can be measured with an indirect coombs, has to be tested. If there is a high indirect coombs in the mother, and the baby is hydropic, then you pretty much have to assume that this is an immune type of hydrops. If you are pretty certain that it's not immune hydrops, and we could talk about that a lot more, and if you want me to, then please comment below, but if you've decided that this is not an immune hydrop situation, and it's non-immune hydrops, then the next thing that you need to do is get a very good family history from the parents. As we said on the first video, a lot of the causes of hydrops can be genetic, so it's important to get a really good genetic history. So is there any kind of genetic diseases that run in the family? What about cardiac diseases, congenital heart diseases, or arrhythmias? What about alpha thalassemia? Also, what exposures has mommy had during pregnancy? Was the mother exposed to anybody with slap-cheek disease, which is parvovirus, or did the mommy change the kitty litter, which, as you all know, can transmit toxoplasmosis? So always, as like everything in medicine, start with a very good history. Then, obviously, to make sure there isn't any kind of structural abnormality, especially a structural abnormality of the heart, the fetus needs to have an excellent ultrasound of its whole body, checking the kidneys, checking the heart, checking any large cysts that may be present anywhere. Sometimes these babies may need to be sent specifically to a cardiologist just to make sure that no anomalies are being missed or the baby doesn't have an arrhythmia or anything. So going down the algorithm, if the hydrops is non-immune and there doesn't seem to be any structural abnormality and there's no arrhythmia, then the next thing that needs to be figured out is whether this baby is anemic or not. Does the baby have a low blood level? So the way that you can check for fetal anemia is by checking the middle cerebral artery velocity, or MCA. So remember, the MCA is one of the arteries that supplies blood to the brain. And like we've said multiple times on this channel, that the baby's body is going to do everything that it can to make sure that the brain, really above everything else, is getting the oxygen that it needs during pregnancy. So if the baby is anemic, then the brain will be working extra hard trying to pump that blood and the oxygen through the brain to make sure that the brain at least is getting the oxygen that it needs. So you can imagine that if there is a little bit of anemia, then the blood will probably be pushed through a lot faster trying to make sure that more and more of those oxygen molecules can be gotten to the rest of the brain. So obstetricians and MFM specialists can literally get an ultrasound with a Doppler of that middle cerebral artery flow, and they calculate like the peak speed, the peak velocity that that blood is going at. And it's calculated in centimeters per second. Then they compare the speed of the blood going through the middle cerebral artery to the average expected speed of the blood going through the middle cerebral artery for a baby that age. So it's calculated as multiple of median, which is basically how many times faster than the average is this blood going at. If the blood is going at 1.5 times or more faster, then the baby is considered to be anemic. This is incredibly sensitive, which is obviously very, very helpful. And it's really revolutionized the way that these babies are diagnosed with anemia. As you can imagine, before this was all figured out, then these babies needed to be prodded and proked, you know, mostly through the umbilicus to actually measure the amount of blood that they have. So this has really revolutionized the OB care in this standpoint. And not only that, it can test for anemia, but if the baby is then given a transfusion, then normally the MOM falls back to normal too. As a caveat, per the OB colleagues, it is kind of an absolute number. So if the MOM is above 1.5, then you can assume that the baby is anemic, but it doesn't really have a gradation. If the MOM is two, it doesn't mean that the baby is more anemic or three or thereafter. So it really is a yes or no, is the baby anemic or not? If this anemia is hemolytic, then as we've already talked about, then when there is hemolysis or breakdown of the red blood cells, you're going to end up with increased bilirubin. So if you do end up getting some amniotic fluid, then the more bilirubin there is in the amniotic fluid, then the more hemolysis there is and probably the more anemia. And this test is the basis of the spectral analysis of the bilirubin in the amniotic fluid. So it's still kind of an indirect way of knowing how much anemia that baby has. But obviously to figure out exactly what the baby's blood level is, you need to sample the baby's blood directly. And this is done with PUBS. PUBS stands for percutaneous umbilical blood sampling. So this is where under the guidance of the ultrasound, a catheter is inserted into the baby's umbilical vein. And this is also a pretty incredible procedure from somebody that doesn't do it. But not only can blood be sampled when PUBS is being performed, so you can take some blood out and measure the hematocrit of the baby, but it's also a way of giving the baby medications, for example, antiarrhythmia meds, or giving the baby blood directly. You can do that through the PUBS. As you can probably imagine though, it is a pretty invasive test and it comes with its own risks. So obviously the two big risks would be precipitating preterm labor as well as actually causing a fetal bleed. Then continuing down the algorithm, if we do find out that the baby is anemic, then we need to find out where is that blood going? Is the baby losing the blood or is the baby breaking the blood down or is the baby not producing blood at all or not producing enough blood? So one of the places where a baby can lose blood is directly into the maternal circulation. So maybe there's like a tear or something in the placenta and the baby's blood gets into maternal circulation. In the mother's blood we can test this with a Klyauer-Becky stain. Honestly, I never say that word. I always call it a KB stain. I'm not even sure how it's pronounced. But we do a KB stain on mother's blood and that will show how many fetal red blood cells there are. Obviously, the higher the number of fetal red blood cells, the more we're worried that this was a pretty major component of a pretty big bleed from the baby. As you all know, torch infections can also cause anemia, whether it's from increased breakdown, which can happen in syphilis, or decreased production that can happen in parvovirus. So you probably should be sending levels for toxoplasmosis, parvovirus, syphilis, as well as CMV, which can also cause anemia. And there's lots of different tests that you can send, but I just want to remind you all about this because I feel like this confuses people a lot. If a mother has a positive IgG for any of those diseases, then that means that she's had that infection at some point in the past, and it doesn't necessarily mean that it's an active infection. If she's IgM positive, then that means that it's more likely to be an active or at least a subacute infection. So if you see IgG positive, it does not necessarily mean that that is the cause of the baby's current problem. And then of course, genetic causes for anemia should be considered, especially places where a genetic issue is endemic. For example, in Southeast Asia with alpha thalassemia. And kind of one of the clues that a mother may have alpha thalassemia is that her MCV or kind of the size of her red blood cell may be on the much smaller side than you would expect. At this point, I just want to point out that in the table, wherever the algorithm ends, it's recommended that in a baby with HYDROP, some sort of genetic testing is done. So in utero, that could be direct genetic testing on the baby's blood. It could be genetic testing from the amniotic fluid, or it could be non-invasive testing on the mother's blood. So obviously we're using kind of the little fetal cells that get into the mother's blood to check the DNA on that. So what if there seems to be no obvious structural abnormality on the ultrasound and the baby is not anemic? So here we're following the algorithm down the left side of the chart. Here, again, an amniocentesis is recommended with genetic testing, and again, testing for torch infections. And here you start thinking about kind of rare genetic diseases that may not have any obvious structural anomalies, something like a lysosomal storage disease. And then the third set of arrows is when you actually find a structural abnormality on the ultrasound. As we keep saying, in all cases, you should do some sort of genetic testing, but then further testing is going to depend on which abnormal structure was seen on the ultrasound. Right, let's go on to part two. So what is the treatment of hydrops? Anybody that's watched any of this will realize very quickly that loads and loads of different disease processes can end up with hydrops. So obviously the treatment is going to depend on what the diagnosis is. So like many things in medicine, we really want to do three things, which is A, figure out what's causing the hydrops, which disease is causing the hydrops. B, we want to treat that disease or cure it if we can. And C, we want to support the baby through the hydrops, hopefully until it resolves itself while we're treating the baby. In the first part, we talked about how testing needs to be done, and obviously treatment is going to depend on what was found during the testing. A lot of these treatments can happen when the baby is still in utero. So for example, if the baby is found to be anemic, then you can give the baby a blood transfusion, as we talked about through pubs. If the baby is in SVT, so has a very rapid heartbeat and cardiac arrhythmia, then the baby needs to be brought out of SVT, normally by giving medications. If there is a twin-twin transfusion going on and the baby is hydropic because of that, normally kind of like the recipient baby, then we need to do an ablation. So anything that can be done in utero would be way better than either delivering the baby early or waiting for it to be too late. If the baby is hydropic though, and we don't know what caused the hydrops or there isn't a treatment for it, then sometimes we do have to deliver the baby early. And obviously when this is done, it needs to be in a center where people are going to be ready to take care of a hydropic baby, preferably where there is a whole multidisciplinary team that can take care of this baby. If there is time and we're delivering the baby early, then just like all babies that are delivered early, the babies will do better if the mother is given prenatal steroids. So if there's time, give the mother prenatal steroids. And then whether that mother should be induced or should be delivered by C-section is kind of the same decision as is always made whether a baby needs to be delivered by C-section. Is the baby too big to get out vaginally? Is the baby in too much stress to be able to go through labor or the baby needs to be delivered immediately because maybe of non-reassuring fetal heart tones, then obviously a baby is delivered by C-section. Remember, and we always talk about this in general neonatology as well, if the baby is hydropic and has a really high chance of having a lethal anomaly, then the question should always be made, should we put mommy through a emergent surgery, an abdominal surgery, if the baby has a very low chance of survival anyway? So that's obviously a discussion with the team. All in all though, about two thirds of hydropic babies are delivered early. Before the delivery in a lot of cases, you have an idea about whether there is a pleural effusion or ascites, something that you may have to drain just to get the baby breathing and everything. But even if you weren't told that the baby definitely has any of these, if you are told that you are going to the delivery of a hydropic baby, then you pretty much have to assume that you may need to drain any of these cavities or all of these cavities in the delivery room to get the baby breathing and to get a good heart rate. So anytime that you're going to the delivery of a baby with hydrops, make sure that you have a good team with you because these are babies that may need a lot of extra hands and also come prepared as if you may be draining the pleural space or the ascites. So you have to bring a bunch of 18 to 20 gauge angiocatheters, bring some syringes, bring some three-way stopcocks so that you can actually pull the fluid out. If the baby is hydropic or known to have hydrops because of anemia, then make sure that when you're going to the delivery room that you can have some emergency blood pretty quickly available or basically O negative blood or trauma blood, whatever you call it at your facility. But remember, in hydrops, just like with every baby, you're not aggressively doing stuff in the delivery room unless the baby is not responding appropriately. So you're still going down the NRP algorithm. So you'll only try to drain something if you can't get the heart rate up, if you can't get the oxygen saturations up. You're not gonna give blood if the heart rate is above 100 and the baby is sat in 95% on room air. But because a lot of these babies are preterm and a lot of them can be sick, then very often they will need some sort of respiratory support, whether it's nasal cannula, whether it's CPAP, whether they need to be on the ventilator. So you don't aggressively have to intubate these babies, but just realize that if they do have these different effusions and you feel like they haven't been doing well prenatally, then give a slightly lower threshold to actually intubate these babies rather than wait it out five minutes of giving positive pressure ventilation, even if the heart rate is kind of okay. If after intubation, the baby's saturations or heart rate is still really low despite good positive pressure ventilation and everything, then at that point, if you see the ascites or you know there's ascites there, or if you know there's a pleural effusion, then at that point, you may need to either tap the chest or tap the belly to try to relieve that fluid so the lungs can open up a bit. You're generally not doing a pericardial tap in the delivery room. If there was a cardiac tamponade, then you'd probably know it before delivery. Then once you've stabilized these infants, obviously, you need to get them to the NICU, and in the NICU, just like always, we need to give them the respiratory support that they need and give them the fluid support and nutritional support that they need. Very often, we do put umbilical lines in these babies. If there's any concern for an infection at all, for example, syphilis, then you immediately start antibiotics. In the beginning, we're not generally feeding these babies because they're normally pretty unstable, but once you've kind of stabilized them out, even if they still do have a pleural effusion or ascites, you can start feeding these babies. Then obviously, if you didn't have a diagnosis for the hydrops, then at that point, you have to start kind of going down the same algorithm that our OB colleagues would have gone through prenatally. So first of all, now that we can see the baby, do an extremely good physical exam. Look for any dysmorphic features. See if you can feel the liver down or whether there's any hepatopenomegaly. This could be consistent with a torch infection or with an inborn error of metabolism. Then you're usually sending some initial blood tests, so definitely be sending a CBC, looking for anemia, maybe also syphilis, parvo, toxo, looking for any sort of torch infections. Very often, it's helpful to get a microscopic exam of the placenta. So if you can send the placenta to pathology, that can also be very helpful. This could show that, for example, the mother had a kind of tumor, like a chorioangioma, or maybe there was syphilis that is found on the placental pathology. Remember, if there is anemia and you don't know if the baby lost it into the mother, then make sure that you send a KB test on the mother. You can just call your OB colleagues and ask them to send it on the mother. If also, you always have to do this, as you can see at the end of all the algorithms, you probably should do some genetic testing on the baby. If it looks like a trisomy issue, so it looks like it could be a trisomy 18, then you send a regular chromosome analysis. If you're not really sure, but there are some just general dysmorphic features, then send a microarray. Then, just like before, you're doing some sort of imaging as well. So you should be getting images of the heart, of the kidneys probably, and maybe if you are really concerned about the amount of ascites or pleural effusion, then you might just want to document exactly how much fluid there is there. Obviously, the next steps that you take are going to depend on what you find in all your testing, but you do obviously have to support the baby while you're kind of figuring out what the baby has. If you correct the underlying issue, so whatever caused the baby to have hydrops in the first place, so baby had an arrhythmia, is now hydropic, and you correct the arrhythmia, then the excess fluid in the different compartments, whether it's in the skin or the belly, should slowly get reabsorbed by itself. So you don't have to actually tap the fluid in the belly or in the lungs just because it's there. The only reason why you actually drain that fluid from the pleural space or the peritoneal cavity is to make sure that the baby can breathe better. So if the baby's having a lot of problems with blood pressure or heart rate or oxygen saturation, then yes, you do have to drain those. But otherwise, you can just wait and allow the body to naturally reabsorb that fluid. Another reason why you might want to tap it, even if the baby's kind of doing okay, is to figure out if it really is kind of a serous, just kind of like remnants from the blood, or if it's a chylothorax, so it's kind of more a more lymphatic-type fluid. And that's what we call a chylothorax. I talked a little bit about this in the first video. A chylothorax normally is a resultant of leaky lymphatic fluid or there's a blockage in the lymphatic system. And when you tap that and send the fluid for a cell count, you'll see that the fluid has more than 85 to 90% lymphocytes. If the baby is being fed enterally, and obviously the milk that the baby's getting has some fat in it, then that fluid, that chyloseffusion, will look really milky. But if the baby is not being fed enterally, even if the baby's just getting smoth through the vein, then that fluid will just look really yellow. So to figure out whether it's a chyloseffusion, it is important to actually send the cell count. The milky fluid will only give it away if the baby is being fed. Unfortunately, most of the time, that chyl doesn't really go away by itself. So very often that does have to be drained until the baby's leakage problem or lymph problem hopefully slowly heals itself. Chylothoraces are kind of like this whole other beast. So if you're interested in us talking about it, then please mention it below in a comment. And number three, let's talk quickly about outcomes of babies that have had high drops. Obviously, as you can imagine, if a baby with high drops is more premature, then they are going to have a worse outcome, just like everything else in neonatology. In a recent study done by Tolya et al, which identified more than 2,000 infants with high drops, 46% of infants were discharged home, 36% of infants died, and a further 18% were transferred out of the system. So we have to assume that some died and some were discharged home. Overall, it's about a 50% survival of infants born with high drops. So not a high survival. They also showed that the lower the gestational age of the baby and the more edematous the baby, then the worse the survival was. And obviously the sicker the baby was at birth. So if the baby was intubated and needed pressers, then the survival was worse. And obviously the cause of the high drops is also going to affect the survival. So if you have a CDH, a congenital diaphragmatic hernia, and high drops, then your mortality rate is 90%. If you have arrhythmias, it's 13%. If you just have a perforated bowel, and generally the GI causes of high drops have a very good survival outcome, but the mortality rate is about 10%. Another study done in China had very similar outcomes, maybe slightly better survival rates, but they also found that the worst survival outcomes were in babies with chromosomal or genetic disorders. And there is a link to both of those studies below. And what about developmental issues? Again, there are so many different diseases that result in high drops, and so many other variables that are involved, like how sick was the baby and how premature was the baby, that it's difficult teasing out exactly how much the high drops itself affected developmental outcome. Generally though, like all babies that have spent time in the NICU, especially if they're premature, they are at increased risk of having slightly worse neurodevelopmental outcomes. And so all of these babies should be followed by a developmental specialist. Okay, and that sums up everything that we were going to teach you all about high drops. If you want to know anything else, or you have more specific questions, then please comment below. In the meantime, please remember to like this video and to subscribe to this channel. We really appreciate you being here. Thank you.