Subtitles section Play video
Let's go over chapter 6 cardiovascular. I'm going to start with just three OTC medications. There really aren't that many.
Let's start with OTC anti-hyperlipidemics, you'll see these called anti-cholesterol drugs, or
things like that
there's, I put that they're over-the-counter
but they're also by prescription, and it's a little bit goofy
so the omega-3 acid ethyl esters are
actually Lovaza, which is a
which is a brand name for the prescription
omega-3 acid ethyl esters, and then niacin has a brand name of Niaspan, but you can still find
niacin and
fish oil
over the counter, which have essentially the same thing. So what's the what's the advantage of getting the prescription?
the FDA has tested those particular
medications the omega-3 and the niacin and to know that it's FDA-approved to know that it's at that level of purity
that can be an advantage.
The big OTC cardio drug is something that's been around for a long time
which is aspirin, but it's
used a little bit differently. So instead of the
325 milligram aspirin as an analgesic or for fever
we're talking about 81 milligrams
and
we used to have something called children's aspirin. We now know that aspirin can cause Reye's syndrome
spelled capital R-e-y-e-s, but pronounced rise like I rise in the morning and
this aspirin at 81 milligrams does a good job of keeping the platelets from getting sticky, and there's good
outcomes with morbidity/mortality
in terms of cardiac events like heart attack like stroke. So a daily aspirin
the physician tells the patient to take it but they can just find them over-the-counter.
But a very inexpensive way to help the patient and then just a reminder that this brand name, Ecotrin
is "enteric coated aspirin"
to help protect the stomach
from this non-steroidal, but again this aspirin is not being used for pain it's not being used for fever
It's being used because of its ability to thin the platelets.
Well the first prescription group
we have is going to be the diuretics and
with the diuretics what you want to do is in your mind picture the glomerulus and from the glomerulus
we want to go to the proximal convoluted tubule
then to the Loop of Henle
then to the distal convoluted tubule then to the collecting duct
and I say distal convoluted tubule and collecting duct as separate but
Really, we're talking early distal convoluted tubule but
that doesn't really matter as much as getting the order right
and the reason this order is so important is that diuresis
decreases as you get further away from the glomerulus
So if you think about being on a waterslide at the top of the waterslide
there's a lot of water coming out into that slide
But as you get to the bottom there's just a little trickle down at the bottom
same thing's true here, so the osmotic diuretic
mannitol [brand] Osmitrol. This is used for brain edema a very serious event but not used that often
So, the next group are the loop diuretics they work in the Loop of Henle, and we have furosemide and
This has a stem -semide stem. So there's torsemide, furosemide
other diuretics and the
the brand name comes from the fact that it lasts six hours so, Lasix
and this loop diuretic is used more for congestive heart failure or
severe edematous states where there's a lot of fluid that needs to be taken off
Or it might be used if the fluid needs to be taken off quickly.
When you're talking about treating hypertension, you could use furosemide,
but more likely you'll use a thiazide diuretic like
hydrochlorothiazide, abbreviated HCTZ
One of the brand names is Microzide, it was the capsule form.
And these thiazide diuretics are more used for somebody who has hypertension.
So if you look at again the diuresis, the mannitol would be the most, furosemide might be a little bit less,
hydrochlorothiazide less than that.
The issue with both furosemide and hydrochlorothiazide is that they decrease
potassium and because they decrease potassium we need to in some way get that potassium back.
So we have what's called a potassium sparing diuretic
Triamterene is one. It doesn't cause a significant amount of
diuresis because it really works closer to the collecting duct and the triamterene is
paired as a combination product with hydrochlorothiazide -- again the -thiazide stem
and triamterene's brand name was Dyrenium
and you take part of the hydrochlorothiazide or the ending to make the brand name Dyazide, so this was
d-y-r-e-n-i-u-m or used to be
but we don't really see that brand name on the shelf ever.
Potassium sparing: so
some triamterene alone is potassium sparing, spironolactone is another one. It's known as Aldactone
and while there's no stem here, know that
spironolactone
affects aldosterone and that a-l-d that's in the front of aldactone
is really referring to that
aldosterone that will retain sodium and water and then by blocking that sodium and water
Then we'll have some amount of diuresis and we'll hold on to the potassium, so they'll be an exchange
electrolyte replenishment
often with loop diuretics just adding a potassium
sparing diuretic wouldn't be enough. So you would need to have electrolyte replenishment
with potassium chloride and to make the brand name they took
the K from kalium which is the
symbol on the periodic table of elements for potassium and then D-U-R for duration, long duration.
So a potassium supplement that has a long duration
and again with diuretics you really want to memorize them in this order
from the glomerulus to the proximal convoluted tubule up the ascending Loop of Henle to the distal convoluted
tubule and then to the collecting duct to remember which has the most diuresis,
which has the least, where are the potassium sparings all the way on the other side by the collecting duct.
So from the diuretics we're going to go to the alpha
antagonist, the alpha agonist, the beta blockers, and talk a little bit about hypertension.
So the first thing I want to go over is alpha and beta
if you weren't in a Greek letter society you might not know the Greek alphabet
but the first two letters of the Greek alphabet are like our A and B
except we call it beta [Bay-tuh] if you were to go to the UK they call it Beta [Bee-tuh]
which actually makes a little more sense that it sounds like the B and our A
and B in the first two letters of the alphabet,
but the important thing to know is that if you
block the alpha-1 receptor you're going to get
vasodilation and then if you activate it you get vasoconstriction, so to treat hypertension
we want a lower blood pressure. To lower blood pressure, we would need to vasodilate
so we would use an alpha-1
antagonist or an alpha-1 blocker, and then it looks like a little fish with a 1 if you want to make the little
Greek form of the alpha, but the -azosin is the
stem and there's other drugs: terazosin, doxazosin [docks AH zo sin]
I've also heard it pronounced doxazosin [docks uh ZO sin]
but I've always pronounced it doxazosin [docks AH zo sin]
and then Cardura, it alludes a bit to cardiac or some kind of long-duration drug
the alpha-2 agonist clonidine, you can see this as a patch and
clonidine it's also used with
ADHD treatments, but in this case you want to maybe think about the brand name as
"catabolize blood pressure" or to lower blood pressure in some way or another and again
I put up the fish or backwards fish the alpha-2 is how most people will refer to it
just because it's a lot easier than writing out a-l-p-h-a-2
beta blockers fall into three generations
there's the important
part of the beta blocker name or the stem is the -o-l-o-l
and if you put those l's together o-l-o-l
you get two backwards Bs and you can think beta blocker
Inderal is the brand name [of propranolol] and the
way that you want to think about it is it blocks all of the beta receptors, so first generation beta blocker
it's non-selective it affects beta-1 and beta-2
so that it affects beta-1 is good it reduces heart rate
that it affects beta-2 is not good because in an asthmatic this can be problematic if
you have a something that blocks beta 2 receptors
then you would cause bronchoconstriction.
So just remember we have one heart, beta-1. We have two lungs, beta-2.
Beta blockers second-generation: so atenolol
metoprolol
are all very common beta blockers the difference is that we're only affecting beta one
so in this way atenolol and metoprolol are
similar but what I want to call your attention to are these salts and these aren't
stems, these are salts and
if it's a tartrate salt then it is short acting or shorter acting and if it's succinate
then it's longer-acting.
So someone might take one tablet a day versus two tablets a day depending on
which salt they have, so
if you just say metoprolol sometimes you're not giving enough information
to let us know, well, which one did you mean?
Beta-Blocker third generation: so carvedilol
I see a lot of
videos that say the -lol is a stem. It's not.
-alol is a stem. -olol is a stem and -dil- is a stem or at least an approved stem.
What it looks like they've done with this generic is they've recognized that Coreg affects beta-1 receptors
beta-2 receptors
but also has a vasodilatory property to it, so
having that d-i-l in there lets you know that it's a vasodilator and that d-i-
that d-i- really took the place of what would have been that first "o" to make -olol. So to remember it,
just think, okay
I would have had -olol, but I added this d-i-
and then I have the -dil- to let me know it's a vasodilator, and it has beta blocking activity as well.
Why would this be something that we want to do? Well if you lower heart rate, then your body is naturally going to
vasoconstrict to get the blood pressure back up. The body doesn't want the blood pressure to be down
so by vasodilating and lowering
heart rate then we're doing two things to maintain that
hypertensive patient in a normotensive state
So that's the alphas and betas
this next group comes from something called the
RAAS so the Renin Angiotensin Aldosterone System
so renin is an enzyme that converts angiotensinogen
it's a zymogen. If you want to think of a fire extinguisher with the pin in it
That would be a zymogen and if you pull the pin then you use the fire extinguisher
so angiotensinogen becomes angiotensin 1
but you still have to do something before the fire extinguisher will fire
so you can think of angiotensin converting enzyme
as the hand that actually pushes that fire extinguisher
making I guess would be carbon dioxide I'm not sure what gas is in there [to] make it work
so by going from angiotensinogen to angiotensin 1 to angiotensin 2
you now have a potent vasoconstrictor, so that's how it works
physiologically to raise blood pressure.
So, what we want to do though is lower blood pressure
so we would block that second enzyme, the angiotensin converting enzyme itself, and we have an ACE inhibitor
so an angiotensin converting enzyme inhibitor
and sometimes people call them the "pril's" because they always end in -pril or
enalopril lisinopril
So the renin was that first enzyme, the angiotensin is second,
the angiotensin one is second then angiotensin II is third, but then what about this aldosterone?
Well aldosterone
retains sodium and water as its physiologic purpose, so we're going to want to block that
to allow for the secretion of sodium and water and then in secreting the sodium,
it exchanges from potassium as a potassium sparing medication so
understanding the way that the electrolytes work is critical in the RAAS, and then it all comes together as a system
but what if a patient develops a dry unproductive cough?
And this can happen with angiotensin converting enzyme because of its effect on bradykinin.
What we do is not treat it. We don't give them codeine or we don't give them
dextromethorphan, what we do is we switch them to an ARB or an angiotensin II receptor blocker
So instead of affecting the enzyme, we're going to block the receptor itself
and some people call these the "sartans" because they all end in -sartan or s-a-r-t-a-n
and you can see some clues to
cardiac in the RAAS if you look at Cozaar backwards
It would be r-a-a-z or looks like RAAS and then Benicar, benefit cardiac.
Never came up with anything for Diovan
but the -van in Diovan takes the V and the last two letters of -sartan so again
understanding that ACE inhibitors, we've known them for a long time. They work very well
but you might switch a patient over to an ARB if there's some kind of non-productive cough caused by the ACE inhibitor.
All right, so let's go to calcium channel blockers and
two very different kinds of calcium channel blockers, one that
vasodilates and affects the heart and one that just vasodilates
so the non-dihydropyridine CCB's or calcium channel blockers
are the ones that affect both the heart and
cause vasodilation. Why is this important? Well beta blockers can be used as anti-dysrhythmics,
calcium channel blockers can be used as anti-dysrhythmics if they're in this non-dihydropyridine class.
So diltiazem has the -tiazem stem
[brand name] Cardizem and you can see cardiac in there
and verapamil which ends in -pamil with the p-a-m-i-l stem.
And you can see the brand name Calan, the Ca- for calcium
Or the cal- for calcium and then -an for antagonists or part of channel,
number of different ways you can look at it to remember it's a calcium channel blocker.
What's important, and I'll give you a story is that my daughters, when they were...
After my wife had her cerclage procedure to keep them in, she needed a calcium channel blocker to keep
the children from coming back out and the calcium channel would block...
If we used non-dihydropyridines, then we would suppress heart rate
not only in my wife, but also in the three fetuses, and we wouldn't want to do that.
So the choice was one of these two, amlodipine and nifedipine and we ended up having
Nifedipine prescribed, but nifedipine only
vasodilates, and it was a very low dose
so it was just used as something off-label, but
There is a huge difference between the two and that
both groups vasodilate but only the non-dihydropyridines affect the heart directly
And then both of the brand names, Norvasc, you can think of vasculature
and then Procardia,
'cardia' has to do with the heart and then this -dipine [stem] you can find
in dihydropyridine you can find the d-i-p-i-n-e
so d-i-p-i-n-e and you actually have more choices but
my students looked at it as, well yeah we see the -dipine, but we also think of a dip in blood pressure
so the d-i-p and then the -i-n as a way to remember what it's for.
So moving from those vasodilators to a single vasodilator like nitroglycerin
nitro- is the stem. I didn't see it on the USANC, but I did see it on the World Health Organization and
The brand name Nitrostat means you know certainly, we're using nitro, and we're doing it very quickly or STAT.
The HMG-CoA reductase inhibitors,
these are known as the "statins"
because of this ending and this is the stem -statin
but you really don't want to use just statin you want to use this infix -va- or the -vastatin because
there's an antifungal called Nystatin that has this s-t-a-t-i-n at the end as well
and you don't want to confuse those. So atorvastatin is Lipitor
sounds like the lipid gladiator
And then rosuvastatin is Crestor, and you can think of
cholesterol, there's a couple letters from cholesterol in Crestor
the fibric acid derivative, so the -fibrate is
the stem and this is Tricor and
the reason they named it that way is because these fibric acid derivatives affect
the triglycerides or help with triglyceride lowering.
So those are some medications again for hypertension and some other uses, for cholesterol.
Let's go and finish up with some
anticoagulants, cardiac glycoside, and then one anticholinergic.
So the big difference between the anticoagulants is if they're parental or enteral
So enoxaparin ends with -parin and that's the stem and that's Lovenox
and then heparin, I didn't want to put a brand name because we've been using it so long
it doesn't really, it does sort of have one, but I just left it like that
But notice that the parenteral and -parin are sort of alike
this parenteral isn't "parent" like someone
had a child it's the word "para" meaning outside of enteral, and we just got rid of the second a.
So something parenteral is outside of the GI
Something enteral is taken by mouth or orally.
It looks like I forgot to put one up there, dabigatran
which is Pradaxa
and -gatran is the stem
And then warfarin and dabigatran are very similar in that they're both
orally... they're both oral
anticoagulants, but warfarin requires INR measurements to make sure that the patient is in the right...
has the right amount of coagulation, it isn't
to the point where they're going to be bleeding or isn't to the point where they're more likely to get a stroke or
something like that, so you can see the letters I-N-R [within -RIN] at the end of warfarin to remind you of that.
Another thing my students used [as a mnemonic] is that warfare
is bloody as a way to remember that bleeding is a side effect or possible side effect of Warfarin.
The antiplatelet, so where the anticoagulants tend to work in the veins, very slow-moving
areas where coagulation happens because of stasis or where the blood slows down.
Something like clopidogrel, an antiplatelet, which is comparable to
aspirin in the way that it works has the -grel stem and
it works on platelets, and you can see the p-l-a from platelets in the word Plavix, so it vexes platelets.
Cardiac glycoside, so there's no stem here
but it comes from the plant Digitalis lanata and
it looks like little fuzzy fingers so the dig- comes from Digitalis and
the Lan- comes from lanata so digoxin and Lanoxin are both I guess homages to the
flower itself that this came from, foxglove.
But digoxin is a cardiac glycoside, so it's a positive inotrope,
increases the strength and force of contraction of the heart
but it also works as an anti-dysrhythmic, so
it used to be used all the time back in the mid 90s
but then they found that sometimes
There's a bit of a danger with it because a patient that has very low potassium and digoxin could go digi-toxic.
Anticholinergic: so the -trop-
stem lets you know there's a cholinergic component, but the -tropine
really lets you know that it's a tertiary
nitrogen compound versus the tropium which is a quaternary compound and this is Atropen and
What we use an anticholinergic for is
so, anticholinergics would cause tachycardia or
increase in heart rate. In some
procedures we're really worried about bradycardia or very low heart rate. So by giving atropine
we prevent low heart rate by giving a drug that causes high heart rate
It's one of the four drugs in the LEAN acronym which is
L-E-A-N
so lidocaine
epinephrine
atropine and naloxone
And then these are the drugs for emergencies for various reasons.
So that's cardiac