Virchow's Triad Nursing Explanation (DVT Thrombosis)

Hey everyone, it's Sarah with RegisteredNurseRN.com,
and today I'm going to go over

Virchow's Triad. So let's get started.
Virchow's Triad helps us identify the three main factors

for why a blood clot develops within the deep veins.
So we can look at these risk factors

identified by Virchow's Triad and take preventative measures
in our patients to prevent them from

developing a blood clot. Now, DBTs tend to occur
in the lower extremities like the legs,

but they can occur in the upper extremities, as well.
However, when they occur in the lower

extremities, they tend to have a higher chance
of breaking off and turning into a pulmonary

embolism. So what veins are most susceptible for a DBT?
Well, this includes the veins of the pelvic

area, the lower leg, like the calf and the thighs.
So the specific veins are like the perineal and

the posterior tibial and the calves, or lower leg,
and the popliteal and the superficial femoral,

like in the thighs. So before we talk
about the three main factors for why a blood clot develops,

let's talk about how a blood clot actually develops
and what substances are playing a

role in forming this clot. So regardless of the cause
that's identified by Virchow's Triad,

what happens is that platelets start to collect
at the edges of the vessel. And this is usually

within the cusp of the vein's valves. And here
in this picture labeled as one, you will see the

clot, and it's around the cusp of the vein.
Now, once platelets get on board, these chemicals start

to be released called "clotting factors."
And you can see these are identified by these green little

circles in this illustration. And clotting factors
cause fibrin to be created. And fibrin causes the

big problem because it's going to allow our clot
to form together because fibrin is like strands

of like this mesh. And this will cause
white blood cells, red blood cells, and more platelets

to stick together within that vein. And it's going
to form this nice clump, aka a clot. Now,

unfortunately, what can happen is that this clot is going
to continue to grow. And you can see in

this illustration labeled as two, that it's growing.
And then if you look down at picture

three, it's going to break off, and it enters
into circulation. And whenever it's in the vein,

it's going to flow with wherever the blood flow is
going with the vein. And we've learned that

the venous system, it flows back to the heart.
So this clot that's broke off is going to flow

to the heart, and it can enter into the pulmonary
circulation and become a pulmonary embolism

and cause serious health issues. Now it's a Virchow's triad.
And just as the name says triad,

that means it's a group of three.
So we have three main factors. And to help you remember

those three main factors, remember the word "she."
So S stands for stasis of venous circulation,

H is hypercoagulability, and E is endothelial damage.
And whenever you have those type of

factors presenting, you can get a blood clot.
And that's demonstrated in this picture right here.

This is a picture of a patient who has a blood clot.
Notice the leg that's on the bottom. It's

very swollen. It's red. I bet if we touched it,
it would be very warm to the touch compared to

the leg that's laying beside of it. This leg is not red,
and it's not swollen. So notice the

differences. Now let's dive a little bit deeper
into the stasis of venous circulation. So we want

our blood to flow. We don't want it to just hang out
and become stagnant because if it does,

it starts to congeal and clump together.
And that causes major problems. So blood has to flow back

to the heart via the veins. And it does this
with the assistance of healthy vein valves and the

muscles within the extremities. Like whenever you walk,
your calf muscles help squeeze that blood

back up to your heart. So if your vein valves
are damaged or your muscles aren't working,

or they're just not being used, blood isn't going
to flow back very well and clots can develop.

So again, when blood hangs out together for a while,
it will start to stick together because

of those platelets. So think of some conditions
that will damage the valves of the veins or where

the muscles can't be used because this can lead
to stasis of blood flow. So one cause would be a

patient being immobilized, even paralyzed.
Also varicose veins. We have an issue with the vein

valves. We talked about this in our peripheral
vascular disease video. Also surgery, especially

hip or knee, traveling for long hours
without moving the extremities, or some type of obstruction

like late pregnancy, obesity, heart failure,
like left ventricular dysfunction, or atrial

fibrillation. This is where the atrium are
not really emptying very well and blood is just

hanging out and clots can form. Then we have
hypercoagulability. And just as the name says,

hyper means "high," increase, coag, that's dealing
with the coagulation of our blood. So there's

something in this patient's body that is causing
their blood to have a high risk of clotting. And

this is usually mainly due to a disease process
presenting in that patient's body, or it can be

due to other reasons. So for instance, cancer can
cause this. Severe illnesses like septic shock,

sepsis, we talked about that in our video
whenever we covered septic shock. Also dehydration,

use of estrogen, birth control pills,
heparin-induced thrombocytopenia, and that postpartum

period after a woman has a baby. And lastly,
we have endothelial damage. And whenever you're

thinking about these main factors for the
development of a clot within that deep vein,

you need to think of something that is causing
either direct or indirect damage to that lining

of the vein. But regardless of how it's affecting
that endothelial lining, it's going to stimulate

the platelets and the coagulation process.
So some things that can do that are IV drug usage. And I

have seen this in patients who, you know, they're young,
and they're using IV drugs, and they have

blood clots. Also venipuncture can cause it.
Indwelling devices in your patient such as a

central line, an IV line, or even a heart valve
can cause a clot. And medications that are really

hard on those veins, or some type of trauma or
injury to the vessel like surgery. Okay, so that

wraps up this review over Virchow's Triad.
And don't forget to check out the other reviews in

this series.