Pediatric Asthma – Pediatrics | Lecturio

[Music] in this lecture we're going to talk about pediatric asthma and how we should approach a wheezing child so we see this all the time a child who's six years old who comes in to see you who and who has wheezing on exam an expert ory high-pitched noise this child may be in moderate respiratory distress he might have a runny nose or congestion or a cough so what is your medical diagnosis how do you make that medical diagnosis let's drill down on asthma so before we even get started though I want to talk a little bit about the difference between Strider and wheezing there's a simple trick to be able to help you make a differential diagnosis and a patient who has wheezing versus a patient who has Strider and I don't want to make that very clear here is a child with lungs an airway and two main stem bronchi if we were to imagine that this child had accidentally swallowed a ball and the ball had landed up in the throat area but had not entered the cavity of the chest we might imagine that when this child breathed in there was a negative pressure created below this ball and that airway space would tighten as a result while breathing in this child would make a noise a sort of noise which is from the narrowing of the airway against the ball while breathing in but while breathing out you can imagine that this air would blow past the ball enlarging that area around the ball and allowing for a silent exhalation patients with Strider typically have noise on inhalation for this very reason but not so much an exhalation this would be a classic noise for example in group which is a viral inflammation of the upper airway now of course patients can have inspiratory and expiratory wheezing but this is classically how we think about Strider wheezing on the other hand let's now imagine this ball was a little bit smaller and made it all the way down to the right mainstem bronchus or in this case the left mainstem bronchus it doesn't really matter the point being though that now when this child is breathing in the airway is expanding and this is because the entire lung is expanding so the space in that airway is actually getting bigger and typically the patient will not have any noise while breathing however when breathing out that area is now collapsed down and you can see that now the airway will be pressing up against the ball and the child will have an exhalation alloys so wheezing is typically on exhalation more than it is on inhalation now in a patient with asthma you can absolutely get inhalational and exhalation or wheezing as a result of generally very very narrow in Airways but we'll typically see the exhalation always first so if you see a patient with wheeze what could be causing it there's a lot more than asthma it causes wheeze and it's important to know the difference especially if the patient is never wheezed before in the infancy period zero to one years patients may very likely have bronchiolitis bronchiolitis is a viral inflammation of the lung it does not cause smooth muscle constriction typically and it's mucous balls or it's very small amounts of mucus collecting in these Airways which caused a narrowed space and absolutely present with wheezing if a patient is wheezing they may very well have bronchiolitis and not asthma especially if they have upper respiratory infection symptoms like congestion bronchopulmonary dysplasia can present with wheeze a foreign body can absolutely present with wheeze usually that's in one location aspiration in general if a child has oral motor dysfunction and has a hard time swallowing some of that liquid might have gotten done with their lungs or anatomic abnormalities of the airway can also cause wheeze for instance a sea cam or congenital cystic adenomatoid malformation may be pressing on that airway in the age 1 to 4 we often see virally induced wheeze again bronchiolitis this may be a case of early asthma this again might be a foreign body especially if it's rapidly onset mom found the child was normal one minute and the next minute was wheezing and this might be the age at which a child is presenting with the pulmonary symptoms of cystic fibrosis over five years of age it's probably asthma patients can totally have vocal cord dysfunction which might cause both Strider and wheeze patients may have a hypersensitivity pneumonitis or patients may get something more complex like allergic bronchopulmonary aspergillosis which is an allergic hyper responsiveness to Aspergillus in the environment so if you see a patient with wheezing what are the key questions to ask well the first is at what age did wheezing begin if this is the first wheeze we're gonna manage it a little bit differently than if this child has been wheezing for a long time knowing the age of wheeze in starting will help you with the differential diagnosis you should ask whether this wheezing is episodic or persistent was it sudden onset which might be a foreign body or gradual onset which might be asthma is it associated with triggers every time the child in is in his dusty grandmother's house he starts wheezing that's a strong indicator of asthma or has it responded to albuterol in the past if a child has a history of wheezing which is responsive to albuterol this is probably asthma so when you're getting at asthma is a diagnosis it's very important to get a sense of how severely ill is the patient because in asthma the key is control and prevention so you'll want to ask whether they have many events per week or less than one every two weeks you we'll want to ask about nighttime awakenings frequently these children will awaken with cough and that's a good sign of asthma out of control it's important to ask about whether this asthma interferes with normal activity can the child do sports like the other kids if the child does have asthma it's incredibly important to know how often they're getting systemic steroids systemic steroids as we'll talk about in a bit have a lot of side effects and we want to avoid those does the child have a history of previous hospitalizations or does the patient have previous visits to an intensive care unit these are all signs of asthma out of control one key historical fact is was this child premature premature infants have a much higher risk for asthma than non premature infants and that can tip you off as to what's going on so if you are examining a child who you suspect have asthma it's important first off to note their overall appearance and whether they have respiratory distress in a child with asthma who is in respiratory distress we are going to first address their respiratory distress and later ask the question about whether maybe this isn't asthma or some other disease in other words the typical paradigm you learn of what's the differential diagnosis and now how do we manage the patient is put on hold in asthma because we may not have time to address their differential diagnosis first we need to jump to what is what most concerning because asthma represents by far and away the most common cause of wheeze and children we're gonna just address their asthma first if they're in grave respiratory distress and do studies later we're gonna check their respiratory rate and their lung exam very important to know what is it sound is there air entry throughout is there wheezing throughout is it inspiratory and expiratory wheezing do they have rhonchi which might be bronchiolitis or do they have crackles which might be pneumonia this will help us distinguish these things it's important to note their heart rate and their cardiac exam keeping in mind that albuterol once it's gay is absolutely going to cause tachycardia as a side effect of the drug but if they're having a high heart rate it may be because they're afraid or they have air hunger but it may also because they're having problems with oxygenation it's important to examine the liver in an asthmatic and that might not seem totally obvious right off the bat but remember in asthma the problem is getting the air out its obstructive lung disease these patients are hyper-inflated and it would be very unusual to fail to appreciate a liver in other words if you put your hands under the right look on the right upper quadrant you should feel a liver edge in an asthma who's asthmatic who's having an exacerbation so expect a little bit of a liver edge in these children it's helpful to find allergic stigmata things like hives or eczema or other findings in a patient with asthma if you see clubbing or failure to thrive that is not asthma something else is going on and you need to figure out what is the cause of this pulmonary situation so those are the key historical exam findings we're going to look for how do we truly diagnose asthma on your exam they may mention spirometry with post bronchodilator response typically they'll give something like a methyl choline challenge and look to see if they can create bronchoconstriction a response of around 20% is indicative that this patient is reacting to the methyl choline challenge the reality is that we don't typically use this test it's probably not cost-effective the vast majority of children we simply use a history of responsiveness to albuterol and other stigmata like eczema to make the diagnosis of asthma rapid viral testing is not helpful viruses can be a trigger for asthma viruses can happen in patients with bronchiolitis too and the sad issue is is that if you look at healthy children walking the street one-in-four will test positive for a virus so viral testing is neither sensitive nor specific consider allergy testing or pulmonary function testing really only in children who are over 5 years of age who you're having a hard time controlling or where you're really not certain of what the diagnosis might be for a child with a previous diagnosis of asthma who's coming with an asthma exacerbation we are not going to typically get labs or x-rays we simply treat the patient for hospitalized children with no history of wheezing a chest x-ray is usually done this is because again while we're gonna start off pursuing that presuming this child may have asthma it's also possible the child has another problem which you haven't figured out yet an example would be a foreign body or another condition maybe a pulmonary lymph node that's compressing the airway this is the kind of thing where they can look very similar at first and then over time you notice they really aren't responding to the albuterol like you might expect a chest x-ray can sometimes be helpful in distinguishing between these problems so back to asthma we have a patient who's coming in with an acute exacerbation they're wheezing there right there in your office what are you gonna do well for the acute exacerbation the mainstay is albuterol albuterol is a powerful beta agonist it's going to cause bronco dilatation and allow those Airways to really open up patients should feel relief relatively quickly there is an available levo albuterol or racemic albuterol it's more expensive but not more effective so most people don't use it sometimes we use it because it may have less cardio toxicity to children with underlying cardiac conditions but for the vast majority of patients with asthma it's not necessary additionally during an acute exacerbation we are going to give systemic steroids this can be oral or it can be IV or it can be interim us killer neither root is better than another they all take about two hours to kick in if you recall it's a complicated pathway that steroids take to actually reduce inflammation the steroid has to make it into the nucleus of the cell which then changes via transcription factors the production of both prostaglandins and leukotrienes there's this back filled pathway that if you apply a steroid it takes about two hours before you're going to really notice those steroids kicking in but they will kick in in two hours so get them started as soon as you can the other important thing in an acute exacerbation it is a learning moment so perhaps not while they're acutely ill but after they've started to get better it's a good time to counsel about triggers because prevention is what asthma care is all about so in the acute setting you may see more than just albuterol used if the albuterol really isn't turning the child around the corner they may use continuous albuterol through a nebulized machine but there are other medications that can help as well an example would be magnesium magnesium has is a 2 plus ion just like calcium and thus is a competitive inhibitor in the sarcoplasmic reticulum of the smooth muscle cell inside the airway so the magnesium is going to allow that airway to relax side effect though is that it really relaxes all your smooth muscle and so you may develop hypotension terbutaline is sort of like IV albuterol its intravenous we use it in pregnant women to prove it to help with toca lysis but in children with albuterol it's given IV and it'll cause more of that smooth muscle dilatation and usually a profound tachycardia children are terbutaline are usually worked watched in the ICU setting when they're in the ICU setting you'll note that we like to avoid intubation if a patient's and respiratory distress from say a trauma or a bad pneumonia we usually will go get around to innovating them pretty quickly in asthma we're gonna generally drag our heels on that and the reason is remember asthma is a problem with getting the air out if I now innovate the child I'm going to be pushing more air in and I'm worried about a pneumothorax where that lung may actually pop and air may escape enter the side of my chest wall causing a pneumothorax that's not very good there are some other agents that can help ketamine is a bronchodilator and some of the inhalational agents like halothane or bronchodilators there are many different agents we can use in the ICU setting to help dilate those smooth muscles so in the hospitalized child who's not in the ICU how are we going to manage these children well generally we're gonna start off with continuous albuterol in some places they do that on the wards in some places that's in the ICU setting only and generally you're gonna have a continuous nebulizer of albuterol very high doses then when the patient is feeling better they'll generally transition to every two hours or q2 we'll watch them we'll use asthma scores to see how they're doing and once they've been stable for a few treatments we'll switch them to q4 or every four hours at that time they're almost ready to be discharged and in most settings we'll wait for two q4 our treatments and if they're still looking good they're okay to go home we typically discharge them if they do not have an oxygen requirement if they do not need albuterol more than every four hours for at least two episodes and if they don't have respiratory distress so when we send them home we want them not to come back again and the way we're gonna prevent them from coming back again is by maintaining a better control of their asthma than they've had before to decide about control we first have to decide what type of asthma have let's talk about the different categories of asthma intermittent asthma is sometimes called mild intermittent asthma that's where you have exacerbations now and then but it's by no means a regular condition then you have mild persistent moderate persistent and severe persistent these children have more and more frequent exacerbations and we'll walk through what that means but one key thing to remember is asthma in the United States is getting more common and more severe deaths in asthma are at an increased rate now than ever before children in the intermittent category of asthma are likely to die just like any other category so categorizing them as intermittent doesn't mean you no longer pay attention to their asthma it means they need less control or medication and that's why we're determining their category how do we determine it we ask these questions are you having nighttime awakenings how frequently to use albuterol how much does this Albert does your asthma interfere with your normal activity and how often have you used systemic steroids in this past year now you're going to take this information and you're going to then categorize them into one of these categories these are all outlined in the national heart lung blood institute guidelines but I'll summarize them here for you so if you are an intermittent asthmatic you should have symptoms less than two days a week you should wake up less than two nights per month you should have used albuterol less than two days per week you should have no interference who are their daily activities and you should only be on steroids once a year if you have mild persistent disease these numbers go up where your symptoms are two to six days a week your awakenings of three two - three - four nights a month and your albuterol uses two to six days a week and you have minor interference and that's a subjective call moderate likewise it goes up now you're having daily symptoms your awakening frequently you're needing albuterol every day it's very much interfering with your life and you're using steroids more than two times a year if any of these things are true you're now a moderate persistent asthma tuck and now we get to severe persistent and these patients are very sick with daily symptoms all day long every night they're waking up these patients have extreme problems with getting through their day now we're going to use this category to decide what kind of inhalational therapy they're going to get as a controller when we choose a controller if they are intermittent and between five and eleven years old they're just going to use the albuterol they don't require a controller if they're mild persistent they'll get two puffs twice a day of a low dose steroid there are some inhaled steroid formulations that are once a day but most are twice a day and you have to make sure they're getting at the right amount moderate persistent they're gonna give a higher dose steroid an example I show here is fluticasone 110 micrograms per puff twice a day and then if they're severe you may add multiple medications this patient is getting both fluticasone and oral montelukast which is a leukotriene inhibitor if they're older we may be a little bit more aggressive once we hit that severe persistent range now we're really talking about using combination therapy of both long-acting beta agonists or là-bas with a steroid long-acting beta agonists alone without the steroid are contraindicated there's a black box warning and it may be associated with death and asthma the data aren't very good but the point is in the United States because of that black box warning all labas or long-acting beta agonists in this case cell salmeterol are combined with a steroid in this case fluticasone this drug is known as advair on the market there's lots of drugs out there it doesn't matter which kind you choose it's simply getting the right category and getting the right treatment for the severity of that child's illness so let's say a patient is on a controller and they've now come in with an asthma exacerbation how do you figure out what the right thing to do is they're already on a controller it may be that their asthma some worse so the first question you ask is is the child taking the controller appropriately the reality is the vast majority of the time the answer is going to be no either that family is non-compliant and is forgetting doses the child often especially in the early adolescent years will stop taking their control because they just don't want to have other possibilities they've got the technique wrong remember the best technique for one of these inhalers that are metered dose inhalers is to use a spacer and in little children a mask and a spacer taking it without the spacer it doesn't work they're just swallowing the medication for the Disqus ones with the powder sometimes it requires a little bit more coordination and that child simply isn't old enough to figure it out so if the child is not taking the controller appropriately then really the best thing to do is to do more education to educate this child into how to use the spacer correctly or to change around what you're using that's more age-appropriate if the child is using it appropriately this is when you really want to step up your controller medication and there's a lot of different ways you can do that step up therapy so for example if a patient has a lot of allergic sequelae they may benefit a little bit more from getting a leukotriene inhibitor added as opposed to stepping up the strength of their inhaled steroid whatever the case may be understanding control of asthma and Prevention of asthma is what's incredibly important to preventing death and preventing long-term sequelae from a patient with asthma thanks [Music] you

Channel: Lecturio Medical

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Keywords: Medicine, Exam Preparation, Medical Videos, Meducation, Medical Education, Asthma, Pediatric Asthma, Childhood Asthma, Asthma Treatment, Asthma Management, Pediatrics, Acute Respiratory Disease, Respiratory Diseases, Pediatric respiratory diseases, inflammatory airway disease, Clinical presentation of Asthma, USMLE Step 1, Pediatrics USMLE, Pediatrics lecture

Id: H6aC6ayHn6Y

Length: 23min 58sec (1438 seconds)

Published: Mon Mar 18 2019