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Current time:0:00Total duration:4:03

Video transcript

hypertension means exactly the same thing as high blood pressure this can be a disease on its own so when people have high blood pressure we can say they're hypertensive or they have hypertension now pulmonary is a word every time you see this it's going to be referring to our lungs so pulmonary hypertension is literally high blood pressure in the lungs now you might be thinking what do you mean how can there be high blood pressure in what seems like a sac of air right or in our lungs but in fact the lungs are very important part of the circulatory system for our blood let's look at really quickly what the heart and lungs do I drew this blue person here to show you that blood coming from the body returning to the heart is blue or low in oxygen we use blue to represent that because the muscles have extracted the oxygen out of the blood and used it so we have our heart here with its four chambers now this is going to be the right side this is going to be the left in medicine left or right is usually flipped as if the person is facing you so their right is your left alright we have right atrium receiving chamber right ventricle from here goes through the lungs left atrium left ventricle so the blood comes in here first blue blood from the body goes into the right ventricle and from here it goes to the lungs let's draw some loans really quickly wind pipes into smaller Airways and our lungs are these two big structures like that and indeed it looks like two sacs of air but the truth is with each of these as they start branching off with all the airways the blood vessels blood supply actually follows the same pattern the same path as the airway so we get a very good system that interfaces between the blood and the air and the purpose of that is to get oxygen into the blood now I'm using red here to draw this just a because blood we usually think of as but remember that it comes in is deoxygenated blood and leaves as oxygenated just to blow that up for you this is our alveolus or the smallest unit in the lungs and air sac and the blood supply would run just along it blue first without oxygen and as the oxygen enters into the blood it turns red so the blood supply leaving the lungs is red all right so we got oxygenated and we need to return to the heart and our red blood with oxygen to the left atrium goes into the left ventricle and from there it goes out the aorta to the body and now we have a red person so roughly this is the path of the blood in our body so if we think of this as almost a circuit where there are many stops along the way the liquid has to flow through you see if I can make this make sense so if we have our body here that's giving blood to the heart is our heart we have our lungs and we're turning to the rest of the body so we need one more unit here into our body of course this is connected it's in a loop so the pulmonary hypertension we have the lungs are clamped down hypertension means there's a lot of resistance in this area of the circuit so basically it's hard for liquid to flow through as you can imagine what would happen is that would have a lot of back up into these parts of the circuit because it's hard to get blood through then when you've back up and then going forward we have not enough because the blood is trapped here it's bottlenecked