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Current time:0:00Total duration:8:17

Video transcript

there are actually two diseases that fall under the umbrella of chronic obstructive pulmonary disease which we just call CE o P D as an acronym the first one of these is emphysema and this is a disease that have to do with airway collapse due to change in the structure of the walls what I'm going to talk about today is the other category called chronic bronchitis chronic bronchitis now both of these are obstructive meaning air is stuck in the lungs and can't get out but in our case in chronic bronchitis the culprit here is too much mucus so that's going to be the theme of the day remember that too much mucus just a quick latin lesson here so chronic over a long long period of time Bronk refers to the lungs and anytime you see itís in a medical context it means inflammation of that area so we have constant irritation of the lungs speaking of which let's draw some lungs so we have the trachea here branching off into the left and right main bronchi and it just keeps pouring off into smaller and smaller segments that's the basic pattern in the organization of the lungs can draw all the levels here just wanted to give you an idea we go like that and of course on this side it's the same thing I'm just not going to draw that right now and keep in mind that along with the lungs we have the blood supply line very close to it and this is where the gas exchange happens back and forth from the blood into the lungs and of course what's going into the lungs is our oxygen and what's coming back out is carbon dioxide in a nutshell that's what the lungs do so keep in mind this gas exchange so chronic bronchitis is what happens when the airway becomes all gunky with too much mucus now mucus in there is a normal thing you and I wouldn't get sick you cough up the phlegm that's basically what it is it's the body's defense mechanism against any irritants that are bothering our lungs as you can see when the space gets all gunked up like that the err going back and forth between the lungs and the blood supply is hard to get across in addition it's just going to be hard to move air through see the oxygen is getting in here and the walls just become narrower it's harder to move through the mush that's where all the problems come from so when I talk about irritation it can come from things like being a smoker smoking every day irritates the lungs or if you live in a very polluted place pollution can do that as well which and what goes with that is smog from our cars or this person can have an allergy and the allergens constantly irritating the lungs can lead to this as well so chronic bronchitis is the lungs response it does not specify one kind of irritant so if we have a guy here with chronic bronchitis I'm going to give him some hair because I just think it makes all my stick figures look a little better here we go here's a big fro let's call him Robert or Bob give us some eyes and I'm going to draw his mouth in blue here he's referring to an infamous nickname that people with chronic bronchitis have they're called blue bloaters and you'll see this in every textbook it's kind of confusing why are they blue so let's break this down one word at a time blue is talking about the fact that they're blue as opposed to red if we come back here to the oxygen we think of blood with oxygen in it looks a little bit brighter and more red than blood without oxygen so the lungs job is to deliver this oxygen to our blood supply without this gunk in here since they get not as much air not as much oxygen across this person is going to look a little bit bluish to the tent and the stress up in the lips you can show up in the whites of the eyes can show up in the person's nail beds depending on their complexion sometimes can show up in their skin so blue refers to the fact that they have lower oxygen so instead of having a percentage of oxygen in the high 90s like people usually do high 90s to 100 they might have lower lower 90s 80s depending on the severity and the second word here blow der refers to their shape so if you can imagine this what was his name Bob can't take a good breath in can't get enough oxygen then he's going to take bigger and deeper breaths to try to compensate for that right which artificially increases his chest volume so since this is a chronic disease than over years and years the diameter of his chest actually increases he literally just looks bloated in addition we have carbon dioxide back in the lungs here that are trapped this is when we talk about obstruction in the beginning so it's obstructed in the lungs and can't get out as effectively and that further leads to expansion of his chest diameter so he's just going to look bloated and kind of hypoxic let's write that word again which just means lower oxygen not enough oxygenation so blue blood or someone with lower oxygen who is literally bloated from trying to get more air in and can't get all the air out now the second component they'll have is a very nagging cough now this coffee is actually part of the diagnosing criteria so chronic bronchitis is actually diagnosed through the story so they have to have a cough for three months out of the year for two years in a row this has to be consecutive and this cough has to be productive so there has to be mucus phlegm that they're coughing up and that pretty much diagnoses chronic bronchitis so this cough has to be present and what makes this cough happen is you can go back to our lungs here embed it in the green per annum of you can see this but in the tissue of the walls of the lungs they're a smooth muscle so in response to all this irritation going on the smooth muscle spasm and that's how you get the cough it's a reflex we can't help it it's our body's natural way of getting rid of irritants and when it goes overboard we have chronic bronchitis now another component I wanted to mention is that even though chronic bronchitis is a chronic disease you can have a cute flare ups or cute episodes or something gets a lot worse this can happen when our patient has a cold they can have the flu by the way this is why it's important for people with this disease to get flu shots or I can just even happen from it being winter in the air being cold because cold air also irritates the lungs and causing spasm of the Airways and can make the coughed worse the acute flares can happen when there's a double whammy to the irritation of the lungs so the mucus goes even more overboard and sometimes one section of the lung can be just clogged off one little branch these are so much mucus here now it's a rule in the body that anytime you have complete obstruction like that the bacteria will build up behind it anytime you have bacteria build up you can have infection in the lungs we call this pneumonia so normally it can be bacterial or it can be viral but in this case if it's a blockage of this of the mucus is very likely to be bacterial and once you have infection on top of obstruction it makes it even harder to clear the infection so now Bob is in real deep trouble so part of the treatment is to not only prevent acute flares but to treat them aggressively so coming back to the beginning like I said the theme of our day is mucus production as you can see a person with chronic bronchitis will have a nagging cough they'll be hypoxic with not enough oxygen in their blood and they'll be bloated from trying to take deep breaths and not being able to breathe out all the extra air