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Newborn Respiratory Disorders - CRASH! Medical Review Series



hi again everybody we're going to talk about the newborn respiratory disorders here on the pediatric questions on the USMLE this is among the most commonly tested as far as topics and that's because when you have a newborn with with respiratory distress it's very important to be able to diagnose this as quickly as possible to know the cause and so they're going to test you to make sure that you're able to do that now respiratory disorders aren't the only cause of respiratory distress in an infant and the newborn but it is perhaps the most common so briefly we're going to go over an initial approach to newborn respiratory distress and this is sort of a general approach to all of these but all of these disorders six of these that we're going to talk about they all have their own unique treatment and so this initial approach is sort of what you're going to do for all babies until you really get the diagnosis down and then there's a specific therapy that you can tailor towards these babies so I want to give you sort of an initial approach because you don't necessarily have the diagnosis right away and so that doesn't mean though that you're not going to treat the baby right away you're not going to treat the respiratory distress you cannot wait until you have a diagnosis so I want to go over the initial approach first we're going to talk about six different causes of respiratory distress that are indeed respiratory in origin one that we're not going to talk about that's respiratory and origin sort of is congenital diaphragmatic hernia reason we're not going to talk about this is because I went over this already in the newborn GI disorders in part two so you can refer back there to hear about that so the Cardinal symptoms of respiratory distress are pretty similar to what you would run into an adult main difference is with the tachypnea the respirations per minute and a baby is probably no the normal range is different than all that for an adult so for a baby tachypnea is defined as for newborn a lease is defined as 60 respirations per minute or more more than 60 60 respirations per minute so if the baby is breathing more than one time per second then this is considered tachypnea and that is one of the main features of respiratory distress things you'll also see is the use of accessory respiratory muscles intercostal and sternal retractions babies are usually really thin and small so it's easy to see that unlike in an adult perhaps expiratory grunting could be heared particularly on auscultation and then cyanosis on room air and I'm going to talk about this allude to this a little bit later on but if a baby continue stab cyanosis and you're giving them supplemental oxygen the origin of the respiratory distress is less likely to be respiratory in origin and more likely to be cardiac in origin so if you fat in mind with the baby with respiratory distress you should immediately order a chest x-ray chest x-ray is going to be the most helpful in in concluding your diagnosis which you should also get blood gases pulse oximetry and routine labs and a blood culture particularly in babies who present a little bit later on perhaps after they've been discharged because they were thinking about from genitals ammonia that can present anytime congenital pneumonia at least can present anytime within those first two months of life in many cases like I said that chest x-ray in conjunction with the history knowing whether or not the baby's preterm or post firm knowing the show of the the fluid knowing if there are any complications during the OB period or during the neonatal period that's going to help you arrive at your diagnosis so the immediate therapy of course should include supplemental oxygen first that's a no-brainer that oxygen should be warmed and mid aside and your you're monitoring your pulse oximetry and you're going to want to make sure that the baby is between a 92 and a 96 percent saturation at least when you're getting blood gases you'll want to make sure that the baby is between 60 and 70 millimeters of mercury now we'll just say when you go into intubation if that's where you wind up needing to go and in a lot of babies you do intubation you do run the risk of lung damage that you're if you're too aggressive so that's something to keep in mind you also wanted to monitor the babies for apnea and that's because if a baby has a fear then they're not breathing appropriately on their own and in that case you're going to need to mechanically intubate them babies who are in respiratory distress typically can't feed on their own so you're going to be giving them glucose dextrose either d5w or d-10 W you'll monitor their urine output make sure they're hydrate enough monitor their glucose to make sure that they are getting appropriate nutrition and also monitor their electrolyte levels if they have congenital pneumonia or you think they might have congenital pneumonia particularly if they have respiratory distress and mom is GBS positive or any of the other risk factors if there was a prolonged rupture of membranes then you should administer broad-spectrum antibiotics in addition to of course getting those cultures so as far as intubation and you don't always intubate babies you start with so you can start with supplemental oxygen either by a nasal CPAP or by mask but if there is a need to intubate then one of these fuff three things should be present in these three things you're going to always intubate the baby so if there's acne a– or if the baby has a oxygen saturation our pao2 of 60 millimeters of mercury and the baby is on 60% or greater of fractionated oxygen or if the paco2 goes above 60 millimeters of mercury so if either of these three things are present you're going to intubate the bait apnea pao2 of 60 millimeters of mercury or less with 60% of fio2 or if the baby's PA co2 goes above 6 millimeters of mercury and like I've alluded to earlier cyanosis that doesn't respond to supplemental oxygen it is more likely to be a cyanotic congenital heart defect than if it does respond and you should know that the most common newborn congenital heart defect that presents that neonatal period is transposition of the great arteries overall in Pediatrics the overall most common cyanotic congenital heart defect is tetralogy of fellow but that tends to present later on so when you're talking about cyanotic congenital heart defects that present in the neonatal period particularly with respiratory distress the most common is actually transposition of the great arteries so hyaline membrane disease is also known as respiratory distress syndrome and the reason I don't like that term I like hyaline membrane diseases respiratory distress syndrome is really a bad term there's a lot of things that cause respiratory distress but hyaline membrane disease is really keying in on the cause of this respiratory distress those particular respiratory distress so this is the most common cause of respiratory distress in the preterm neonates and so anytime you have a preterm baby you should keep this in mind if they have respiratory distress this is the most common now it certainly doesn't affect all preterm babies babies that are born between 35 and 36 weeks of gestation which would be considered a late preterm baby it only affects 5% one in 20 so definitely not all preterm babies are going to have this even babies who are severely preterm 26-28 weeks of gestation so that would be a baby born at seven months right around that third trimester beginning of the third trimester only 50% wind up having hyaline membrane disease so not all babies who are preterm are going to have this but definitely keep it in mind so the cause of this is a surfactant deficiency and surfactant develops later on in fetal development we don't have enough of it however you're going to have collapsing Airways when you start breathing and this is going to result in a dilemma –ss when you look at the chest x-ray so the symptoms of course include respiratory distress a decreased air movement which is going to resolve and reduce lung sounds when tousle tation and then of course nasal flaring and grunting which we would see in respiratory distress anywhere the diagnosis is going to be made both on your clinical presentation and all chest x-ray chest x-ray is indispensable for most of these so you'll see diffuse bilateral I like that so this is going to be everywhere in the lochs because when you have a deficiency of surfactant it's not a deficiency in one place or the other it's a deficiency everywhere so this will be diffuse bilateral atelectasis you can also see air Branca grams and then hypo inflation the treatment here is going to be supplemental oxygen via nasal CPAP you want to make sure that you're giving the baby oxygen first because that's absolutely necessary for survival and then intubate the baby for surfactant administration and that surfactant is the ultimate treatment definitive treatment for Highland membrane disease there are there are a couple ways that you can treat this expectantly so if a mother is in preterm labor one of the ways that you can prevent Highland membrane disease if I administering corticosteroids to her and this is really only effective if it's administered around 24 hours before delivery the baby needs some time to respond to this and so the corticosteroids what this does is it accelerates lung development it accelerates the production surfactant and so this reduces the risk of Island membrane disease you'll give the mother an injection of betamethasone and try to delay labor so that the time that the delivery occurs that is around 24 hours after the administration of the betamethasone another way that you can prevent this or at least treat this expectantly is by giving a baby artificial surfactant prophylactically for all neonates born at less than twenty seven weeks of gestation and the reason for that is once you get below 27 weeks of gestation the majority of babies are going to have Island membrane disease that falls right in between where 50% of babies are born with hyaline membrane disease so we treat them expecting them so here's an example of Island membrane disease you see that there's hypo inflation here and you can also see that there's this diffuse ground-glass appearance and this is how to elect asses again here you see that you don't really have you can't really even tell where the where the diaphragm begins and the and that the lungs start so there's really severe add electives this is a little less severe so perhaps a baby that's been treated for a little while but again you can see kind of a ground-glass appearance of the of the lungs transient tech hip knee of the newborn is something that you will see in term babies preterm babies post term babies alike this is more of a function of how the baby was delivered how the labor went but this is a much less severe disease than some of these other ones we're going to talk about this is a temporary respiratory distress usually this is mild severity and the reason this happens is because of retained fetal lung fluid so that's it's the cause and that fetal lung fluid is otherwise absorbed during labor absorbed into the arterioles and into the circulation so that the lungs are nice and dry when the baby takes its first breath the reason that the baby will retain fetal lung fluid as if the baby is delivered quickly sorry prematurely but delivered delivered quickly so if the baby or the mother has a short second stage of labor which is sort of that delivery stage and the mother is pushing that can cause it because usually that's the period where the baby is reabsorbing the lung fluid or if there is a c-section in which rep sharp membranes has not occurred so these things are going to what this basically means is you're going in you're taking the baby out a little too quickly so that can either happen accidentally or it can happen be at regenexx essentially where you're doing the c-section and your ruptured membranes have occurred yet so the baby has not reabsorbed the fetal lung fluid this can be diagnosed by chest x-ray this should be particularly considered in the term baby who has respiratory distress what you'll see is retained fluid all that usually shows up as peri hilar streaking as well as opacity along the interloper fissures because you have you have fluid in between the lobes of the lungs and you'll also see hyper expansion the treatment here is nasal CPAP you don't really otherwise and do anything else besides this that these babies will then absorb the fetal lung fluid and resolve this will resolve spontaneously within the first eight life so it's kind of hard to see here because the picture is a little small but what you see is peri hilar streaking this is a better one where you can see the you can see the fluid collection in between the lobes of the lungs as well as the streaking all right next thing is meconium aspiration syndrome and this is just as it sounds an aspiration of amniotic fluid containing meconium usually the meconium is passed either due to significant fetal to stress or in post term babies so those are the two populations you need to think about these symptoms here are going to include a course respiratory distress course breath sounds they can have a barrel chest appearance and of course when the water breaks it's always important to know how the water looks it's clear that's good if there's meconium in the fluid then the cone ium aspiration syndrome is a problem because we know that the baby has passed meconium and if they pass meconium they can breathe that in for diagnosis here it's going to be chest x-ray but also the clinical presentation there's meconium in the show that's a big big red flag that this baby could develop meconium aspiration syndrome i'm chest x-ray it'll show irregular infiltrates this won't be a few simple traits because this may just happen in some parts of the lungs and not others you can also see hyper expansion and in severe cases you can actually see flow Barre consolidation meconium aspiration syndrome can cause a chemical pneumonitis so that's something to keep in mind the treatment here is general neonatal resuscitation based on the baby status on delivery you should suction the baby's trachea if the baby is either Brady Karthik if the baby has poor respiratory effort or if the baby has poor muscle tone if the baby appears fine and there was meconium in the show then all you need to do is just suction the baby's baby's nose and mouth area to get that meconium out if there is ever meconium in the show you should you should alert doesn't sewing consult Lee you should alert the neonatologist on staff because this is a possibility and you'll want them to be there for the resuscitation efforts the pros that at babies so baby said have meconium aspiration syndrome should be put on positive pressure ventilation and also careful monitoring of their saturation there generally admitted to the NICU and it's useful to insert an umbilical artery catheter to monitor their ABG's reason that's useful is because by putting in that catheter you don't need to go poke them all the time and if you're poking them all the time it's going to upset the baby they're going to they're going to have an increased oxygen demand and that's going to exacerbate things so an umbilical artery catheter is generally indicated in meconium aspiration syndrome of course with inserting an umbilical artery catheter you want to also make sure that you get an x-ray afterwards to make sure that it's placed correctly you also want to monitor their hemoglobin they should be oxygenated to keep over 13 grams per deciliter and okay so make sure that you're communicating with a neonatologist on staff so you can see how this is a lot different than Highland membrane disease and that this is a this is irregular you don't have that diffuse ground-glass appearance you see irregular streaking irregular infiltrates and that's the meconium that's causing inflammation chemical inflammation infiltration of the Frank Amol tissue you can also see hyper expansion compared to Island membrane disease where it's hypo expansion again here to irregular congenital pneumonia is something that can present in up until now we've been talking about things that will present in the baby in the first date or so congenital pneumonia can present in any time and within the first two months of life and usually it will present later on attacking four or five days or later usually after the baby's been been discharged so the lungs are the most common site of infection in the neonate and usually the bacteria that's acquired that causes congenital pneumonia is acquired from the vaginal tract during delivery and presents in the first two months of life so some of the risk factors of course are if the mother is GBS positive that's going to certainly increase your risk of developing child pneumonia since GBS is the most common organism that's isolated if the rupture of membranes was more than 18 hours if there's maternal fever if there's chorioamnionitis or if there's premature labor those are all risk factors for congenital pneumonia most common organisms for congenital pneumonia are GBS and e-coli the symptoms include respiratory distress adventitious lung sounds like we would see in anybody with pneumonia and temperature instability important to keep in mind that neonates do not present like adults they're not necessarily going to have fever so you can see you could see a normal temperature you could see fever or you could see a lower temperature so you don't you don't always see fever but that's something really important just in general to keep in mind in babies who who have infection you can also see more septic symptoms as well for diagnosis you get a chest x-ray this will show diffuse infiltrates atelectasis hyper expansion blunted costophrenic angle ingles what does this sound like it sounds like hyaline membrane disease with those diffuse infiltrates the difference is this presents late highland membrane disease presents within those first few days of life so this presents differently from highland membrane disease these babies will likely have been able to breathe okay earlier and then they develop congenital pneumonia whereas with highland membrane disease they had difficulty breathing from the get-go anytime where there is respiratory distress and you cannot rule out congenital pneumonia you should always get blood cultures right away and in fact most of the time when you're dealing with when you're dealing with a fever and a newborn or temperature instability and a newborn or really any septic appearance and a newborn you should always get pan cultures and that's including your blood your CSF and your urine even if the diagnosis is a parent is a parent because you want to know exactly where that infection has spread to so anytime excepting symptoms a new barn you're going to get hand cultures the treatment is broad-spectrum antibiotics of course ministered after you take that culture and then supplemental oxygen and these babies will be admitted if the baby wow I spell that wrong if the baby does not show signs of improvement then you can consider starting them on IV acyclovir because herpes virus can cause pneumonia as well so this looks just like hyaline membrane disease so you really have to keep in mind your clinical presentation and how old the baby is most things again you see a diffuse infiltration you can see lobar consolidation in congenital pneumonia that's possible and you can also see that in Konya aspiration syndrome as well that's a pneumonitis but it's not as common as in adults okay this one is a big one I would bet that you will for sure get tested on this one because this is an emergency so Coen Allah trivia is a male development of the nasopharyngeal tract and that results in an obstruction and this occurs in approximately one in seven thousand births there's about a two-to-one female preponderance and this is going to result in a life-threatening respiratory distress when it is bilateral so you have a nasal pharyngeal trapped on both sides of your nares if it is only on one side usually the baby is okay but if it is on both sides there is no way that the baby can breathe through their nose and as you know babies are obligate nose breathers so if they can't breathe through their nose they're in trouble this is associated with thyroid suppressing medications as well as smoking during pregnancy so there's a big reason she died right suppressing medications can't really be avoided during pregnancy but smoking certainly can so this is a big reason why smoking in addition to alcohol should be avoided during pregnancy symptoms include a baby that's normal at birth when a baby's crying user the baby's crying when it's delivered but once the baby stops crying it'll become bradycardia and cyanotic and also when the baby tries to feed is the baby can't cry and feed at the same time so if you're talking about a baby that's normal and crying and then become cyanotic and Brady Karthik when crying in Brady Karthik remember in a newborn is less than 60 beats per minute this is a cono atresia you can be reasonably suspected based on this stereotypic clinical presentation maybe that's cyanotic and then cries that was breathing through its mouth and comes okay and then cycles back again but you can also try to pass a 6 French catheter through the nose and if you can't get that if you hit an obstruction then that's very typical of colino atresia and if you suspect colino atresia err on the side of caution and intubate the baby immediately for definitive diagnosis you can get a CT and I'm going to show you some pictures of CT for Conal atresia and that's confirmatory treating the baby it's intubation getting an immediate pediatric ent consult they're going to surgically correct the defect another thing that you should do is get echocardiogram 50% of babies with bilateral Conal atresia will have a charged association and remember the H in charge Association is heart defects so that's very important to keep in mind so here's Conal atresia this is bilateral see here you've got your nares and you're supposed to be going into the nasopharyngeal tract here but you have a blockage and this blockage is in it is normally obliterated during fetal development but in babies who have cono atresia it's not here's another one this is unilateral so you have a blockage here but here it's okay so this baby probably won't present with that cyanosis because the baby can breathe through one ner spontaneous pneumothorax occurs in approximately 1% of all deliveries it's also associated with administering positive pressure ventilation and as well as any kind of mechanical ventilation and that's because of the damage that it can do to the lungs Baro trauma the symptoms here are respiratory distress but also reduced or absent breath sounds on the affected side and shifting of the heart sounds towards the affected side so if you hear reduce breath sounds and then you take your you're oscillation on that side and you hear heart sounds that are deviated towards that side that's probably a spontaneous pneumothorax and this kind of this can happen in any baby the diagnosis here just like in adults with pneumothorax are going to get a chest x-ray it's going to look similar to what adults have you'll see that blackening on the affected side and then you can also see a mediastinal shift for treatment you can manage this conservatively or or more aggressively so if the baby was on room air when the pneumothorax happened so not on positive pressure ventilation or intubated if the baby was on room air and the pneumothorax happened if the baby has not been intubated or has not been on positive pressure ventilation you can go ahead and try a hundred percent oxygen for a few hours and monitor the oxygen saturation and the baby symptoms and if the baby improves in many cases it will be curative however if the baby has significant respiratory distress or if the baby developed the spontaneous pneumothorax while on positive pressure ventilation then in this case you should do thoracentesis or two thoracostomy you should also do thoracentesis or tube thoracostomy if the baby has hasn't improved over a few hours of 100% oxygen also important to keep in mind that spontaneous pneumothorax is associated with renal anomalies so it may be useful to get an ultrasound of the kidneys and possibly even radiographic imager so here's a pneumothorax you see this blackening on the right side and this heart is deviated to the left you can see the collapsed lung right here again on the right side collapse long right here art deviated to the left and then here is a left-sided pneumothorax clearly that the heart is deviated to the right here so you've got your blackening on the left side and a deviation to the right you can also see deviation of the aorta here and I believe that's all I've got for you here you

12 thoughts on “Newborn Respiratory Disorders – CRASH! Medical Review Series

  1. In reading the CXRs of the spontaneous pneumothorax, I thought the heart shifted to the side of the collapse. The hyperlucency in the unaffected side is a result of that lung compensating for the other one.

    So in the very last CXR, the collapse is of the right lobe. The left lobe is more "black" because it's now tasked with doing the job of 2 lungs.

    Tension pneumothorax is where you would see the heart shifted to the unaffected side. So if the last CXR were of a tension pneumothorax, then you could say the collapse is on the left side.

    Please correct me if I'm wrong :))

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