Now, whenever I'm faced with a patient
who complains of malperfusion in the lower extremities,
sometimes call claudication or rest pain,
I ask myself some very important questions.
Number one, how far can the patient walk?
Two, is there pain when the patient wakes up?
And three, are there any ulcers
or signs of malperfusion.
With the answers to these three
common and important questions,
one can have a very good idea
of the level of the vessel stenosis
and whether anastomosis is even present.
Let's take a look at some physical findings?
And very importantly, differentiate
claudication versus rest pain.
pain is usually induced with exercise,
but resolves with rest.
And this occurs over
approximately two to five minutes
as opposed to rest pain.
Rest pain usually is in the forefoot and toes
and the pain can be worsened if the
leg is raised or in a recumbent position.
This make sense.
In a recumbent and/or raised position,
there's even further decreased flow.
And sometimes, the pain is
relieved by dangling the foot
or the feet over the bed.
We alluded to this ankle brachial index,
also called an ABI.
As you examine the pulses,
check every pulse from the abdominal
aorta down to the femoral system,
popliteal, dorsalis pedis and posterior tibial system.
How can you objectively identify whether or not
there is a pressure drop gradient
from your brachial to your ankle?
Well, it’s by the angle brachial index.
or the ratio between systolic
blood pressure in your ankle
and the systolic blood pressure in your arm,
less than 0.4 is highly suggestive of rest pain.
Any ratio less than 0.7
likely induces claudication.
Remember, ankle brachial index
is extremely sensitive and specific.
And additional studies are usually
not necessary to simply diagnose
peripheral occlusive arterial disease.
But remember, imaging may be
useful for surgical planning.
Unfortunately, routine laboratory
studies are unlikely to be helpful
unless there's some infection going on.
Whether it's an non-healing
toe or a gangrene,
you may see an infection and an elevated
white blood cell count as a result.
Let's move on to some
helpful imaging diagnosis.
Using a duplex, again,
it’s operator dependent.
It's an ultrasound technology that
introduces no radiation to the patient.
The duplex has the additional
advantage of giving velocities.
Recall, velocities are
higher in stenotic regions.
And with a Doppler or ultrasound,
we can also get some anatomic idea.
Next, this image shows a
fairly classic CT angiography.
Arteriograms is the gold standard0
for diagnosis of vascular disease.
As a multidetector slice CAT scan’s
cross-sectional imaging improves,
CTs are slowly replacing invasive arteriograms.
Here, highlighted by the circle
as well as the arrow,
this arteriogram shows narrowing
and occlusion in the tibial system.
If you look further down the extremity,
you notice that there are
some wisps of contrast filling.
That's called reconstitution and runoff.
magnetic resonance imaging
is being used for arterial disease.
Here, you see a nice depiction of an MRA.
There appears to be some occlusive
disease in the right lower extremity.
given all the cross-sectional imaging,
modern technology allows us
to do 3-D reconstructions.
Here, you see a nice example
of aneurysms just above the knee.
They’re marked in red.