so finally we'll talk about the pathophysiology associated with ventilation and respiration and we're only going to really hit some of these topics um kind of give an intro because we'll talk about these in detail in the airway breathing chapter and of course the respiratory emergency chapters and then of course things like uh chest trauma things that are going to uh inhibit the ability to ventilate um so we'll go in in detail uh further in the course but for right now I just want to kind of give a um an overview of some of the pathopysiology that you'll see in your patients and when things can go wrong and how that affects uh getting oxygen into the blood and carbon dioxide out and we've already seen some of these already but um um but this will just be a good overview of everything so some of the pathologies that you'll see um I kind of break them off into about seven different problems that can happen with the respiratory system uh first one's ambient air deficiency and oxygen we'll talk about that very briefly uh the patency of the airway uh and we've talked about these already uh increased uh resistance to air flow through the Airways uh decrease compliance lung compliance um increase distance for diffus Fusion we've we've talked about that with water or fluids in the down in the avoli that the oxygen has a harder time diffusing into the blood and then of course carbon dioxide so we'll talk about that very briefly as well um also decrease profusion to the lung so we'll talk about two different times when we get um a decrease in blood flow to those alvioli and then um finally we'll finish up um with a decrease or no nervous stimulation uh allowing for the patient to breathe or or or stimulating the patient to breathe uh as we learned uh previously that the the brain controls ventilation so if we have a stroke or trauma to the brain stem uh the patient's not going to breathe very well if at [Music] all so basically we can take that list of seven and F and further just put them into two different categories that might help you um the first one any condition that's going to decrease the ability of the patient to ventilate whether it be an airway blockage um a air a um a uh respiratory disease that causes the respiratory tract to to spasm like with asthma or a trauma to the chest that the patient cannot generate that negative pressure that they need to ventilate uh the other would be anything that was is going to decrease the ability of respiration or diffusion or the ability to get blood flow to the to the lungs uh the even the ambient air which we'll talk about in a second if if that has a decrease in the ability of or the decrease in the concentration of oxygen in the air it's going to be harder for that patient to get um to to uh get the oxygen that they need [Music] so we mentioned this already the ambient air deficient and oxygen this would be a pathology uh for the not necessarily for the patient but leading to hypoxia for that patient so we know that the composition of ambient air is about 21% oxygen and about 78% nitrogen um one thing that you'll note is that the uh it does say at sea level um now if you go to uh on top of Mount Everest the the um the the pressure of the air is going to be a lot less however uh it's going to be the same concentration or the same percentage of oxygen and nitrogen at the top of Mount Everest and at sea level is is going to be the air is going to be much thinner um than um than at sea level so don't let that fool you and you may see some questions uh on my test or the National Registry that talks about what's the percentage of oxygen in Denver versus the percentage of oxygen uh in Richmond Virginia and and the answer is going to be 21% is just going to be thin uh thin where the pressure is going to be less uh the other thing that leads to uh problems with uh ventilation is the patency of the airway the airway is the conduent from from the outside down to the aviola I remember it's from the out from the from the nose to the avioli is really we need that that patent uh passageway so we can get air down into those avioli so if we um have any obstructions uh whether it be tongue vomit blood or hot dog whatever uh that has to be addressed and and we'll spend significant time in the airway chapter talking about different maneuvers you can do and I'm and I think in lab we talked about that a little bit um but to get just to go in a little bit more DET um um we'll talk about patency and obstruction in the next couple slides um the naso fings for Um this can bleed however you have an alternative Airway you you can open your mouth if your if your nose is clogged for example um however uh bleeding and things like that you can aspirate on that uh so it is important to keep it clean but um um but we still do have that alternate Airway this an constructed nose usually does not pose a major Airway problem at least in adults of course infants breathe through their nose uh so when they get stuffy they have a little bit harder time uh doing that than than we do uh so this is where we don't have the backup because the um there is no Airway there is no alternative uh passageway so uh obstructions in this area they've got to be they've got to be epiglottis um the epiglottis right there can get can get inflamed um this condition is called epiglottitis and that that epiglotis can actually swell and olude the opening and uh and again the point here is just to to kind of overview some of these Airway issues not necessarily to uh learn each of these uh right now all right so I'll kind of group the next couple of items any any increased resistance or decreased compliance will lead to decrease in the ability for that patient to to ventilate and get uh and ultimately G um so we we've already talked about this uh compliance as being the ability of the lung tissue to stretch so that they might have a disease of the lungs where it just doesn't stretch very well or or as easy uh Airway resistance which um can go along with obstructions in the airway but also of things like asthma we have uh reactive disease that can inhibit the ability of air to flow through these Airway passages so if we if we increase uh the resistance um we remember we have to increase uh the work or we have to uh work harder uh to um to to increase the volume of the chest cavity uh another issue that we touched on last time is that plural space can affect the abil the compliance ability uh remember that the two plurals uh two plura come together uh the visceral plura here and the parietal plura here and there's there's this space that's not really a space uh because those two plur are in contact with each other they do have a little bit of fluid between them to keep them lubricated but if we get air for example uh here um that lung would then collapse and uh we would get a a numo thorax and um and that would be uh harder for that patient to take a full uh breath it's it's going to decrease the the ability to breathe if if we have a collapse lung this is a an example here of a pneumothorax on x-ray uh you can see uh this is actually the trachea uh the heart is actually here you can see stuff is being pushed over here this is a uh all this black here is the um is air um the the problem here is it's not just a you can imagine the lung here uh collapse lung here and the nice regular full lung here uh the problem is not so much the collapse long this this long obviously is not in uh being uh helpful in ventilation at all uh the problem here is all this air is actually built up a pressure and um this can actually lead to a decrease in blood returning back to the heart uh which we'll talk about this is a type of shock this is this is not just a pumo thorax uh this is a tension pneumothorax but um uh this is really not the point of the slide the point of the slide is just to show you an extreme example of a of a collapse lung or a pneumothorax uh but a tension pneumothorax is actually deadly and that requires which we do um ALS um not not the not the EMTs unfortunately at least right now I think this might be a skill coming to EMTs but right now uh we would have to relieve that pressure by sticking a needle in there and uh relieving uh the pressure so the blood can continue to return to the heart so I I just show you these just to as we move forward we'll mention these um and it's it's just important to know at this point uh what a pneumothorax is air in the chest cavity it uh it prevents the lung from inflating properly uh but that's not that's not going to kill that patient immediately it will over time because uh they're not able to ventilate um but a tension pneumothorax is what kills uh patients and they need the um the needle decompression of the chest cavity to uh save their life um other pathologies with respiratory system is increased distance for diffusion we talked about this already um when we talked about the we've already talked about this um I know but um just to show you a little bit more so we have uh oxygen def freely diffusing through the avioli through uh the capillary and into the blood carbon dioxide diffusing again from the blood through the wall of the capillary through the avolar wall and now into uh the the avioli uh but what happens when we have fluid um built up in the uh bottom of the avioli for this so if this is all fluid fluid here um to to get to this point so it can be exhaled um carbon dioxide has to diffuse through the um through the the walls like normally but also has to keep going through uh the uh fluid and uh to get here to be breathed out so this can actually cause uh a decrease in diffusion and increase in carbon dioxide in the blood um so that patient is going to feel like they have to use uh more muscles to to breathe and so you'll see that patient having an increase in ventilatory effort uh similarily the oxygen has to diffuse through here uh to get to here so the patient's going to also uh be hypoxic as well decrease in perfusion to the lung so we'll talk about two different times um we get uh perfusion disturbances to the lung tissue uh the first one um trauma if we have blood loss um we're just not going to have as much blood available uh to go back to the lungs and um and get oxygen um and and that's just pretty straightforward if if we have a blood loss it's just not going to be enough to go back to the lungs and pick up oxygen to uh transport uh to uh all the rest of the body especially the brain the other is what we call a pulmonary uh embolism or PE for short uh and a pulmonary embolism here's the word embolism uh embolism is just fancy for a blood clot um so here is a pulmonary embolism and and in this picture here you see the the embolism or the clot gets lodged in the pulmonary arteries and it blacks blood flow so if you can imagine anything all the avioli downstream of that clot is not getting blood so the um so the the air that they breathe in all that oxygen has has nowhere to go there because there's uh no blood flow uh past that alvioli um so it can't all that oxygen that you breede in cannot be loaded into the blood um so those are two different types of uh decreases in lung profusion that will uh decrease the ability of ventilation or actually the decrease the ability of profusion of uh respiration um finally we have a decrease in the nervous stimulation to breathe um and I like this picture just uh it's obviously a um we have a knife here into the skull this is from a real patient um so but it could be anything that causes a brain injury um so so trauma um blunt trauma can uh cause swelling of the brain and put pressure on the brain stem uh obviously penetrating trauma whether a knife or a bullet can uh disrupt the the uh brain stem or even a a stroke where we have a um a blood clot in the um in the arteries feeding the brain and we Downstream from that clot uh let's say that involves the brain stem uh now that patient is not going to have a stimulus to breathe if uh the brain stem is involved we'll talk about so uh inadequate breathing how can you assess your patient um your your patient may be breathing too fast too slow we talked about especially a slow respiratory rate remember a minute ventilation um um cool clammy skin uh meaning remember they're having that fight ORF flight uh response there's danger going on so that they're um they they look like they're not profusing well is it uh a volume issue um or is it a an oxygen issue that they're not getting enough oxygen so they're having that fight ORF flight response uh retractions uh retractions are uh when the tissue actually uh get sucked in um by that by that negative pressure um if if he is really trying to work hard to breathe to get that to to overcome some sort of resistance if if you look here we got cigarettes uh so he's potentially having a uh some sort of COPD issue empyema that sort of thing uh where he has some sort of de sorry increase resistance to um to air flow um to overcome that remember to overcome the resistance we have to work harder we have to increase our work um so uh to do that he's really going to have to generate that very that huge volume that huge chest volume he's really going to have to work and when he does that he actually might suck in tissue um like above the sternal notch is a common sign a common place where we are breathing so hard if you imagine really trying to suck that air down um that actually that tissue can get sucked in a little bit or with every breath and you'll see that kind of be pulled in uh other is uh the um the intercostal muscles uh may get uh sucked in uh the spaces might get uh sucked in with every breath if they're really working hard uh to generate that negative pressure uh irregular Rhythm um that to me would indicate that there is a uh a brain stem issue um and then and of course um so here's his uh brain but here's his brain stem so a brain stem issue if he's has an irregular Rhythm and therefore if he's got an irregular Rhythm um my guess is that he does not is not going to be ventilating very well or potten entially to lose that ventilation uh cyanosis so uh blue that condition where that's blue around the mouth uh increased effort to breathe uh the other point to make here uh let me uh get this off the screen the other point to make here is that he's actually uh what we call uh we call tripoding um with his hands here he's leaned over and uh he's tripoding um and the idea here is he is um he's that helps him open up the uh the volume of the chest cavity shallow breath uh nasal flaring use of accessory muscles we talked about this uh this is the remember the vrg working the apneustic center working tripod position we mentioned that again but any increased work of breathing remember if he has an increased work of breathing he has increased CO2 which means his brain stem um is uh really using these extra muscles Sterno colido mastoid muscle right here uh to really help increase the volume of the chest cavity and that's what it's all about uh if I'm working hard to breathe I'm I'm doing that to increase the volume of my chest cavity because I'm trying to overcome some issue so the patient doesn't have to have all of these for inadequate breathing but this is just kind of a a snapshot of someone who looks like they're they're having a hard time breathing