In this video, Jonathan from the Institute of Human Anatomy, discusses the pathophysiology of asthma, its symptoms, and various treatments.
So today’s video we’ve had tons of requests for it’s a respiratory disorder that affects up to 300 million people worldwide and that disorder is asthma so we’re gonna dig deep into this video and we’re gonna talk about the causes of asthma how they diagnose and treat asthma potential triggers that kind of flare up asthma for people who have it and obviously the
Relevant anatomical awesomeness so let’s get to it so the classic presentation of asthma is intermittent cough shortness of breath or dyspnea which is difficulty breathing and wheezing and these symptoms tend to be episodic meaning they’ll come and go however we can’t solely define asthma based on those three symptoms or clinical presentations because there’s
Other respiratory disorders or illnesses that can come with cough shortness of breath and wheezing so let’s go a little bit further people with asthma or asthma itself is known to be what’s called bronchial hyper responsiveness in other words their bronchial tree is more responsive or reacts to stimuli that don’t necessarily affect people who don’t have asthma so
To go to a little bit more detail of what’s going on this hyper responsiveness of the airway let’s take a look at the cat could avert dissection so this first section i’m going to show is a trachea now there’s some other things above the trachea like the thyroid gland and the voice box or the links and some tongue anatomy but we’re really gonna focus on the windpipe
Right here which again is called the trachea now there’s a couple of things we really want to focus on when it comes to asthma and how the anatomy of the airway affects asthma if you look closely and i’ll bring this closer you can actually see these little rings these are actually cartilaginous rings that help open or keep the airway open now they’re not full rings
If i turn it over to the back side you can see there’s just a membrane and they’re more so like horseshoe shaped cartilage rings i guess you could say now these are really important because they keep the airway open but since they’re not full rings you do still get some flexibility in the actual respiratory airways as far as how it can change its diameter now in
Them brain that i’m showing back here there’s actually a lot of smooth muscle now smooth muscle in the human body is muscle tissue that is not under voluntary control so your autonomic nervous system or the part of the nervous system that just does things in the background does this on its own and what can happen with people with asthma is this smooth muscle can
Actually react or spasm now when an airway constricts we call it bronchoconstriction and in this case if it’s spasms they’ll tank change the name or save a bronchospasm so that’s one component of asthma that we have to focus on if there’s some stimulus or some allergen that makes somebody’s airway react they can get a bronchospasm and that can make it difficult
To breathe now a couple other points i want to make with this i want to show the other dissection here so if you take a look at this this is actually a unique dissection one because this is a right to lung and normally right lungs have three lobes and this one’s unique because it actually has two lobes one and two and we’ll focus on that in a different video but
I want to show you guys here again is the trachea now we’ve cut it in half and so you can actually see the inside of the lining of this trachea running right through there and we’ll get to that again in a moment but what happens with the airway from the trachea is it continues to branch and branch and branch you start from the trachea and you go to a main bronchus
Or principal bronchus you go to then a secondary bronchus or a lobar bronchus and then you go to these tertiary bronchi or what we’ve known as segmental bronchi and i can show you a little bit of that on the actual cadaver here if you look is it’s branching into the lung tissue you can see these branches coming down and branching into certain areas and if i lift a
Little higher you can see those branches coming down as well now why do i bring this up well remember those cartilaginous rings those cartilaginous rings or horseshoe shaped rings are more prominent in the upper airways as you move down they become less prominent and more interspersed and actually when the bronchi branch smaller we call them bronchioles and they’re
Almost non-existent when you get down to the deeper bronchioles however the smooth muscle tends to get more robust or more prominent so think about this during a bronchospasm with asthma if those smooth muscle cells really constrict that can be a problem if there’s no cartilage to help hold it open say in those even lower airways or those bronchioles there are
Certain situations where they can constrict so tightly it will completely close off a bronchial down in the lower airways so that’s one of the concerns that we have to address with asthma that smooth muscle the cartilage lacking in the deeper airways and that constriction or bronchospasm the other component that we have to focus on is inflammation there’s a major
Inflammatory component with people with asthma and i want to show again this dissection so if you take a look here i’m going to open up the airway here and this is the inside of the trachea now the inside lining here is actually referred to as the tunica mucosa and as the inside lining of the tube and yuko so because it produces mucus now that lining can also get
Inflamed and when things get inflamed think about when you sprain an ankle or you’ve had some level of inflammation with sore throat the tissues puff up because in a way they swell up from the inflammation imagine the inside lining of that tube now getting puffy and swelling up that will also contribute to the narrowing of the tube not only that the cells also lined
In that tube will also tend to produce more mucus so think of the three things that now can block the airway during an asthma attack or somebody just who has chronic asthma that’s not well controlled you have bronchospasm where the smooth muscle is constricting the airway you have inflammation of the inside lining that tunica yokoso which can also kind of thicken
That you coastal lining and then also producing excess mucus people can get what’s called mucus plugs that are another way to just plug in the airway and block the airflow from going down into the lung tissue so now that we have an idea of what’s going on in the airways we can kind of really explain those three symptoms that we mentioned the cough the shortness of
Breath and that wheezing whenever there’s air trying to go through a narrow tube it can make a noise and you can hear that when you auscultate auscultate the lungs during say like an exam of the doctor’s office they’ll put the stethoscope on the lungs and listen and hear the wheezing in different lobes or different areas of the lungs you’ll also notice a lot of
Times their heart rate will go up just because their body is trying to compensate and a few guys have ever been to the clinic and they’ve ever put that pulse ox on your finger measures oxygen levels in the blood that often can be decreased when people are having an asthma flare but what are causing these asthma flares what are these triggers or stimuli that are
Causing the asthma to flare up well we have a list of these things that we’re gonna talk about here we have allergens and that can be a lot of different things from pets to dust mites to other things that people are allergic to that list can go on and on upper respiratory tract infections can flare up asthma so like the common cold exercise people have exercise
Induced asthma cold air can be another stimulant that causes an asthma flare gas or chemical irritants that are in the air that somebody breeds in also you’ll see certain drugs beta blockers and we’ll talk about why beta blockers can be a flare in a little bio when we talk about medicine also asthma or i’m sorry aspirin can cause an asthma flare and well that’s
Really interesting is stress or emotional conditions need you to wrap your head around this tomorrow night allegra cole could have her last first kiss so what if you haven’t been diagnosed with asthma yet you’re suspicious that you may have it or maybe your clinician or doctor is suspicious that you have it how will this be diagnosed often they’ll use what’s
Called pulmonary function tests or pft s and i’ll mention a couple of these different types of tf pft s and one of them is called spirometry and with spirometry what you do is you take a really really deep breath in and then you have a forceful quick exhalation and you’ll breathe that or do that into something called the spirometer hence spirometry and they’ll get
Readings based on that now say your readings are low or they’re below average what they may do after that is do a bronchodilator response test in other words if they’re if you’re low on spirometry they’re suspicious of asthma they’ll give you a bronchodilator and which is a medication to help relax the smooth muscle in the bronchial tree and if you improve a certain
Percentage that makes it more likely that you have asthma these are little diagnostic keys to be like okay we have this and we have this asthma is more likely now there are some people who will do spirometry and breathe into that sphere all mature and they’ll be normal but they have this history of cough shortness of breath but that day they’re okay so sometimes
What they’ll do is a bronco provocation test in other words you’re trying to provoke a bronchospasm so they’ll have the patient inhale something a substance called mannitol and that can cause bronchoconstriction and if you have asthma you’re going to be more sensitive to that substance that you breathe in the mannitol that i mentioned is one of the examples you
Can use and that again can give them a key or a cue that that person may have asthma especially if they can reverse it with a bronchodilator so finally how do we treat asthma allegra yes hold on yes we’re gonna toss that asthma inhaler right before you kiss the person of your dreams just like albert brennaman did in that clip it’s kind of epic and cool and funny
And awesome however probably not a good idea because just a little tangent here i cannot tell you how many times i have a patient come into the clinic they’re having an asthma attack and they can’t find their i’ll be drol inhaler so hold on to that thing maybe put a tracking device on it but in all seriousness remember asthma had two main components that we had to
Focus on here we had a bronchoconstriction or a bronchospasm problem and also an inflammatory problem so often we have to deal with both depending on how severe the case of asthma is some people can just get away with what we call a bronchodilator and these are the inhalers that you often see people use in the movie clips that we showed and these have a medicine
Usually albuterol or leave albuterol what are these medicines do again i mentioned they’re bronchodilators they’re known as beta agonist because they bind to beta receptors and they stimulate them just a little clip to the beginning do you remember i said beta blockers can actually stimulate an asthma attack they do the opposite of what the medicine for asthma
Actually does which is relax the smooth muscle and that takes care of the bronchospasm problem but what about the inflammatory component well as asthma gets to more moderate to severe stages we tend to need to use these things called inhaled corticosteroids to reduce the inflammation of that mucosal lining and of the bronchial tree an example medication of this is
Something called budesonide and that’s just one example of an inhaled corticosteroid now a benefit of inhaling a corticosteroid rather than actually taking it in pill form is you tend to have less less systemic side effects and that can really get the medicine concentrated in the lungs will there be some of the medicine that gets into the bloodstream yes but it’s
A lesser effect on other systems say than if you took a pill form that doesn’t mean we won’t ever use a pill form which we’ll get into a minute so what if somebody came up with this idea what if we made an inhaler that both had a beta agonist something that helps with bronchoconstriction or bronchospasms mixed with in anti-inflammatory steroid and they do they have
Combination inhalers where they have these long-acting beta agonists something called formoterol i don’t know if you guys ever heard that that’s just one example combined with the budesonide and they can take that every morning it helps us the bronchospasm as well as the inflammatory component but let’s even go further what if somebody’s using all those medications
And they’re following their asthma protocol but they still have this flare and they don’t know what is causing the flare oftentimes that’s when they come into the clinic and see it see us but we’ll do a lot of the time is we’ll assess them see how severe they are do they need to go to the hospital can we kind of address them in the outpatient setting now a lot of
Times in the clinics that i work we’ll give them a breathing treatment or what we call nebulizer treatment which is you know five to ten minute treatment of a bronchodilator and then often we’ll send them home with oral steroids now a lot of these patients have had inhaled steroids but we almost need to burst them give them a high dose burst of steroids to get
Them out of this inflamed state or this flared up state of asthma and oftentimes five days of those medications do a pretty good job of pulling people out of those major flares of asthma so thanks for watching everyone hopefully that gave you some more information on asthma and just wanted to let you guys know we’re still partners with these guys apparently this
Is what happens when you control your asthma well flowers bloom from your thoracic cavity where your lungs are and that sounded a little bit creepy but oh well anyway i hope you guys have a good time good day and give someone a hug because we need it in the united states right now i’ll go hug justin right now
Transcribed from video
What Is Asthma, and How Is it Treated? | A Deep Look Into Respiratory Disease By Institute of Human Anatomy
