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Current time:0:00Total duration:9:50

Video transcript

when you hear the term pneumonia I think that most of us think about lung infection but not much else besides that and the ammonia really is a little bit more than just a lung infection really in relation to where it is so if we're looking at this image here I want to focus on just lungs that I've drawn out so we know that we have a right and a left lung can't and our right lung I'm just going to draw out some lobes here we know that we've got three lobes in our right lung so we have an upper middle and lower and in our left we've got two and we know that we have an airway so a main airway now don't focus on this yellow line yeah just focus on our main airway so we know it we breathe in air and that air is going to travel down through these smaller branches these branches that branch off and at the end of our airway we have these little grape like sacs so I'm just going to draw a couple just right here so we can see and these little grape like sacs are actually air sacs and we call those alveoli the alveoli is really important because that's where the gas exchange happens this is where ultimately the oxygen is going to end up and where we'll pick up carbon dioxide to exhale out so why is this important well when we talk about pneumonia the pneumonia the infections actually in these air sacs so what I'm doing is I'm drawing these sacs as if we could blow them up millions and millions of times because they're actually very very tiny we have millions of them everywhere at the end of our Airways so if we could blow them up they look something like this now right underneath it I'm going to just keep drawing the the kind of structure that we can expect that we'll see so we have just air sacs have drawn right underneath our air sacs we have tiny blood vessels that run uneat beneath them and all around them and in between our air sacs we just have some lung tissue so I'll just make that this brown color make some lines to represent our lung tissue so when we say that a person has pneumonia the pneumonia infection is actually inside these air sacks and this is where the pneumonia is now anytime that there's an infection or injury in the body the body's response at that site is to cause inflammation so that means that the tissue that alveolar tissue is going to inflame and it's going to leak fluid well that fluid I'm making green and I'm filling up the alveoli with this green fluid do represent the infection it's going to leak out infected fluid into this air sac now why is this a problem well remember we're breathing in air right so let's come over here and make this blue so let's say that here's my air I'm just going to travel down some blue air and I'm breathing that down I'm breathing that down I'm breathing that down and it's coming all the way down to our alveoli because this is where I want to drop off the oxygen so I can breathe and ultimately get the oxygen into my capillaries right because that's what we need the problem is is that I kind of have this block I have this infectious fluid that's blocking that absorption of oxygen and it's going to block that exhalation of carbon dioxide as well and that's a problem with pneumonia it's taking up airspace so as you can see if this person had pneumonia and let's go ahead and even draw it on our smaller grim let's shade in some green into our alveoli here if this person had pneumonia what would we expect to see in them well we can see that we have our air sacs being occupied with this infectious material so think about how that's going to affect their breathing one of the things that we're going to see is dis Nia which really is a fancy term for difficulty breathing the problem that we're having really is shortness of breath so I'll just put short short of breath and that's because looking at our image we see that we're not able to have that gas exchange we can't get that oxygen into our space because it's being blocked by something else they're going to be experiencing chest pain as well and we know that's secondary to the inflammation that's happening at the alveolar love and we have pain receptors in our chest so we're going to feel that how about coffee thinking about all that fluid in our air sacs what do you think the body is going to try to do it's definitely going to try to cough right that's the mechanism that our body has it's going to try to cuff to squeeze out and force out that fluid out of the airways to clear it so we have room to breathe and we keep talking about infection so with an infection you can expect to see a fever that can be low greater that can be high grain so how does this happen how do we get pneumonia infection well there's really two ways so it can be from organisms right just that we get out in the community or it can be from other ways that might not fit into that category so for the first one I want you to think about organism so I'm going to come over to the shoulder and I'm going to draw in a circle that's going to represent my bacteria and I'm going to draw in a little viral illustration to represent a virus bacteria and viruses are certainly the most common causes of pneumonia the good thing is that we have vaccines to combat who are the biggest culprits which would be our streptococcus pneumoniae that's our bacteria and the flu virus these are big big offenders that cause pneumonia infections now when we pick up an organism like a bacteria or a virus and we can also get funguses and Michael plasmas as well we call this community-acquired I'm going to write that here community acquired pneumonia and when I say pickup I mean just in our everyday activities community you're thinking about people so think about work or school or you're out doing leisure activities because you're surrounded by people and if you picked up an organism for somebody that was ill we would call that community-acquired pneumonia now just as we have air we know that the transmission of air into our lungs if we get a bacteria that enters our airway it's going to travel down and it's going to cause this infection now we said we will talk about other ways something that falls under our other way would be ventilator assisted or ventilator fired pneumonia someone artha here ventilator acquired pneumonia I might be better pneumonia so someone's on a ventilator we know that they're connected to a tube that's delivering oxygen to them so let's come over here and actually just erase erase away my my little air symbol that I made earlier that way we can make room for our two I'm just going to put it down to here now in this orange color let's draw in this tube so we know the tube is inserted through the mouth or through the nose and then it's guided down into the airway and it'll end about here so this tube is going to be delivering oxygen to this patient well on the outside this tube is actually connected to a device and so I'm going to write o 2 here because we know that's doing the work of breathing for them well what's the problem with this we know that because it's a direct route from the outside to the inside that things like bacteria viruses other harmful organisms can actually get inside of the tube can grow and cause a pneumonia infection another way that we can get in the mind that doesn't quite fit under our community choir or a ventilator required would be aspiration now aspiration means to breathe in and in this case we would be breathing in something into the lungs that shouldn't be there so let's get rid of our tube so we can visualize aspiration now I want you to really think about patients that are greatest risk for this like patients that have been experiencing vomiting for instance we could aspirate vomit into our lungs now if you take a look at that yellow object I said don't focus on earlier take a look at that now and see how it's moving this yellow object is our epiglottis our epiglottis really direct traffic we know that we have one main tube but this tube actually is split into two one routes going to go to the stomach and one routes going to go to our lungs so let me leave that open for a second and let's let's see the difference so in blue here this is going to be our direct route to our lungs and then in green here this would be our route to our stomach it's all just keep that going down like it's going to our stomach well in the event that our epiglottis is open that means that something can get inside of our airway so in this case we talked about vomit if somebody was vomiting an epiglottis is open we can actually aspirate the vomit into our lungs and because our lungs are sterile environment anything that gets in there that's carrying bacteria is a danger to us because it can make us very sick the same thing can happen with somebody that is eating and accidentally aspirates food into their lungs