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- Hello, my name is Phil Perera
and I'm the emergency ultrasound coordinator
at the New York Presbyterian Hospital in New York City
and welcome to Soundbytes Cases.
In this Soundbytes module entitled part two
of Ultrasound Guided Central Venous Access
we'll look further onto the use of bedside ultrasound
to make a more precise puncture attempt
on the internal jugular vein
during central venous cannulation.
As we discussed in part one, we first wanna map out
the anatomy of the internal jugular vein
by orienting the probe
in both short and long axis configurations
to fully investigate the orientation of the vessel.
We want to use the dynamic technique for real time guidance
of the needle into the vein lumen
and for this we'll need to place the probe
into a sterile sheath barrier to observe sterile precautions
during the puncture attempt.
Here's the needle coming in underneath the probe
in a short axis configuration.
Notice that the sheath needle is coming in
underneath the probe at a 45-degree angle.
And notice that we're using the sheath needle
to first determine the location of the internal jugular vein
by the ring down artifact.
We would use the same approach for the cannulating needle
coming in underneath the probe at a 45-degree angle.
As we discussed prior, the probe should be oriented
in a side-to-side orientation
with the marker down towards our left
as we stand at the head of the bed
so it orients directly to the screen indicator dot
which will be oriented towards the left
of the ultrasound screen.
Here we're localizing the internal jugular vein
using the short axis configuration.
We're coming in underneath the probe with a sheath needle
at that 45-degree plane, pushing in underneath,
and notice the ring down artifact coming in
directly on top of that internal jugular vein
telling us this is the correct puncture point.
This video clip shows why a short axis orientation
is an excellent starting point for cannulation
of an internal jugular vein.
Here we see the echogenic tip of the needle coming down
and permeating the anterior wall of the vessel
and we then note the echogenic tip of the needle
squarely inside the lumen of the vessel.
And we can see how using the short axis orientation
can guide us in a side-to-side orientation
on the patient's neck in terms of lateral needle orientation
with regard to the surface down to the vessel lumen.
When using the short axis orientation
it's important to remember the affect of probe slice
on visualization of the needle tip.
Here we see the probe position one proximally
along the needle shaft
and note in the schematic view towards the left
we see the needle with the tip
squarely inside the venous lumen.
However, the ultrasound probe is positioned more proximally
along the shaft of the needle
and thus on the ultrasound view to the right
all we visualize is the needle above the vessel
even though the needle tip
is squarely right within the vessel lumen.
So we get a false determination of the tip of the needle.
In order to accurately determine
the location of the needle tip
we need to move the probe more distally
as we advance the needle into the patient's neck
along the course of the vessel.
Here we see the probe position more distally
now in plane with the needle tip
in the schematic view towards the left.
And there we can see we can get an accurate determination
of the location of the needle tip
with regard to the venous lumen.
We see the ultrasound view towards the right,
and now we'll be able to see the echogenic tip of the needle
accurately positioned within the vessel lumen.
A second pitfall that must be avoided
when cannulating the internal jugular vein
under ultrasound guidance is to make sure
that the needle tip does not angle to the side of the vein
during a cannulation attempt.
Even though we know the orientation of the vessel
with regard to the skin,
if we don't orient the cannulating needle
along the course of the vessel
it can veer to the side of the vessel
as shown in trajectory's one and two here.
Now if we know the course of the vessel
we can accurately position the needle
so that it goes along the course of the vessel
following trajectory three into the venous lumen.
The solution to avoiding this pitfall
is to know the course of the vessel
as it runs up and down the neck.
We can do this in two ways, the first of which
is to mark two points on the vessel
using the short axis configuration.
The needle would then enter at that distal mark
and aim towards the proximal mark
passing along the course of the internal jugular vein.
We can effectively do the same thing
by passing the probe in the long axis configuration
and knowing how the needle should pass
from the top of the neck down towards the chest.
Here we use a simulation model to show the correct approach
for a short axis cannulation of the internal jugular vein.
Notice here we have the probe in a side-to-side
or short axis orientation and the needle coming in
at a 45-degree angle underneath the probe.
Now remember that we must move the probe distally
to stay in plane with the needle tip
as we advance it underneath the skin
and into the internal jugular vein.
And as we do that
we notice that we've successfully cannulated
the internal jugular vein as shown by the red flow of blood.
And here we see a side orientation of the needle
with regard to the probe.
Here's an actual cannulation of an internal jugular vein.
Notice that we see the deflection
of the anterior wall of the vessel
as the needle pushes down on that wall
followed by the appearance
of the echogenic tip of the needle
within the lumen of the vessel.
So let's watch that again.
Notice the deflection or pushing down of that anterior wall
and then as the needle permeates that anterior wall
we see the appearance of the echogenic tip of the needle
within the vessel.
Here's a different patient receiving a central line,
and notice in this clip we actually can visualize
the echogenic needle coming from the surface
and going all the way down through that anterior wall
of the internal jugular vein to park directly into the lumen
of the vessel.
This video sequence shows cannulation
of the internal jugular vein using the long axis trajectory.
Notice we swivel the probe into the long axis orientation
along the course of the internal jugular vein
as it runs up and down the patient's neck.
By convention again,
the probe marker should be oriented towards distally
or towards us as we stand at the head of the bed.
Notice the cannulating needle will come in
at a 45-degree angle under the distal aspect of the probe.
Remembering that the distal aspect of the probe
or the marker will orient
towards the left of the ultrasound screen,
we can then know to look towards the left of the screen
for the cannulating needle coming down to the vessel.
Here we're performing cannulation
of the internal jugular vein on a simulation model.
Notice here the probe is oriented
along the longitudinal or long axis course
of the internal jugular vein with the marker dot distal
or towards the patient's head.
Here we see the needle coming in at a 45-degree angle
underneath the distal aspect of the probe.
This will allow us to see the entire aspect of the needle
as it travels down from the surface
all the way down to the venous lumen
and cannulates the internal jugular vein.
Here we see the long axis approach
and the needle coming in from left to right
and we know here how the long axis orientation
is excellent for seeing vertical needle depth.
Note the needle coming through the anterior wall
of the vessel and now the needle tip
squarely within the vessel lumen.
Here we can see how the long axis orientation
allows us to plan the optimal depth for the needle tip
with regard to the venous lumen
to squarely secure a cannulation attempt.
Now this is in difference to the short axis orientation
which was better for lateral needle orientation
with regard to the vessel lumen.
So using a combination of short and long axis orientations
will allow you to see both lateral
and vertical needle orientations
with regard to the vessel lumen.
Here's a video clip in the long axis configuraiton
emphasizing the fact that the long axis view
is great for determining the needle depth.
And here we see a needle coming in from left to right
and notice how we can visualize the needle tip
smack within the vessel lumen.
Here's another long axis clip of a patient
who's receiving a central venous catheter
and we see the catheter coming in from left to right.
Notice here the needle tip
deflects the anterior wall of the vessel
pushing it down so that it almost meets the posterior wall.
Thus the needle could easily pass
through both walls of the vessel.
Using the long axis technique
one can best adjust the needle tip depth
and avoid puncturing the back wall of the vessel.
Here's another great use of the long axis technique.
Again, we're confirming that the needle tip
is located within the vessel lumen
and now we can watch as the guidewire
passes through the tip of the needle
and moves down inferiorly
down the patient's internal jugular vein.
This is a great way of confirming
that the guidewire is safely parked
within the lumen of the vessel
before threading the catheter.
Let's end this module with a possible pitfall
that can be avoided by first looking with ultrasound.
Here we have a patient who's had a prior central line
and we notice a thrombosed internal jugular vein
with echogenic material on top of the carotid artery.
When we push down with the probe
the internal jugular vein failed to compress.
In this patient it would be best
to look for an alternative area for puncture
of a central line.
In conclusion, thanks for tuning in for part two
of Ultrasound Guided Central Venous Access.
Using ultrasound for dynamic real time guidance
of the needle into the internal jugular vein
can potentially decrease the mechanical complications
of the cannulation procedure
making the procedure a safer one for our patients.
We can employ a combination
of both the short and long axis views
of the internal jugular vein for optimal results
for a cannulation attempt.
So I hope you'll consider ultrasound
during your next central line placement
and I hope to see you back as Soundbytes continues.

Brightcove ID

5743138573001

https://youtube.com/watch?v=zV3hw_QbgK4

Case: Central Venous Access - Part 1

Read more about Case: Central Venous Access - Part 1

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This video (part 1 of 2) details how the use of bedside ultrasound for placing central venous catheters can reduce the number of puncture attempts, increase patient safety, and increase procedural efficiency.

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- Hello, my name is Phil Perera and I'm the
emergency ultrasound coordinator at the
New York Presbyterian Hospital in New York City
and welcome to SoundBytes Cases.
Today's module is going to look at the use of bedside
ultrasound for placement of central venous catheters,
specifically the internal jugular vein in the neck.
So the question is,
why use ultrasound for central venous access
and why not just use the traditional landmark technique?
Well, interestingly, multiple research studies now show
a decreased number of puncture attempts
are needed using ultrasound guidance
and there's also a lower complication rate
such as lowering the risk of pneumothorax and hematoma.
The US Agency for Health Care Research, the AHRQ,
recommends ultrasound guidance for central lines
right up there in the top 10 patient safety practices.
Ultrasound will allow precise determination
of the anatomy of the vascular structures in the neck
prior to a puncture attempt.
Here's the middle triangle of the neck
that serves as the standard approach for cannulation
of the internal jugular vein.
We see here the branches of the sternomastoid muscle,
the sternal head medially,
and the clavicular head laterally.
Here we're putting our finger into the triangle of the neck
and this indentation between the muscle heads
would be the standard approach for placement of the needle.
We see here that the clavicle forms the inferior
boundary of the middle triangle of the neck.
Within the middle triangle of the neck
run two very important vascular structures
and as per the textbook orientation of the carotid artery
to the internal jugular vein,
we see in the image here that the carotid artery
should run medial to the internal jugular vein
which lies lateral to the artery.
However, unfortunately, there's great variability
in human anatomy and many times the internal jugular vein
can overlap the carotid artery as shown in the drawing here.
Notice the variation in location
of the internal jugular vein to the carotid artery
and many times the internal jugular vein
is located on top of the carotid artery,
making it difficult to cannulate.
Thus, it's important to look with ultrasound
before cannulation attempts to avoid puncture
to the carotid artery.
Here's the high-frequency linear type array probe
that we'll be using to best map out
the internal jugular vein before puncture attempts.
Notice the probe marker there to the side of the probe.
Here are the orientations that we can place
the high-frequency probe in relation to the
internal jugular vein for vascular line placement.
Here to the left, we see the short axis configuration
with the probe perpendicular to the vessel
and notice that the vessel will appear on the ultrasound
screen as a circle, as the vessel will be cut end on.
To the right, we see the long axis configuration
and note the probe placed along
the long axis course of the vessel.
The vessel therefore on the screen will appear
as a tubular structure as shown here
in the image to the right.
Here's the high-frequency linear type array probe
placed over the middle triangle of the neck
over the internal jugular vein and carotid artery.
Now, I like to have the probe positioned
in a side-to-side orientation,
with the marker dot oriented towards my left
as I stand at the head of the bed.
The reason for that is then the orientation
of the probe marker will line up to the orientation
of the screen indicator dot,
which we see here is orientated towards the left
on the ultrasound screen.
Thus the left side of the probe
will orient directly to the left side of the screen,
and this will allow us to orient ourselves
as we place the needle underneath the patient's neck
and cannulate the vein.
Here's a typical appearance of the internal jugular vein
and carotid artery in a short axis configuration,
taken with a B mode or gray scale image.
Note lateral here towards the left and medial to the right.
Here we notice the internal jugular vein in a location
more lateral and superficial to the carotid artery,
which lies deeper and medial to the vein.
We can see the depth markers to the side
and we note the internal jugular vein
at about 1.5 centimeters depth.
Now we can apply Doppler sonography to further
differentiate the two structures
and here again we notice the internal jugular vein
lying lateral and superficial to the carotid artery.
We note the Doppler sonography steady pulsations
of the internal jugular vein that
vary with respiratory pattern
and we can also see the carotid artery
with the pulsations with each heart beat
differentiating the two structures.
We can also press down with the probe
to differentiate the two structures.
The internal jugular vein should compress completely,
while the more muscular outer walls of the carotid artery
should keep it open with compression of the probe.
Here's another video clip showing the internal jugular vein
and carotid artery in a short axis configuration.
Notice here that this internal jugular vein
is much more distended than in the last patient.
Here we see that the internal jugular vein
is located more superficially at about 0.5 centimeters
and that it overlaps the carotid artery medially.
Highlighting the fact that there's great variability
in the course of the internal jugular vein
in relation to the carotid artery,
even within the same patient,
we're running the probe from a position high within the neck
in which the internal jugular vein is seen more laterally,
to a position more inferiorly in which the internal
jugular vein comes to rest more medially
on top of the carotid artery.
Here's a different patient in which the internal jugular
vein is seen smack on top of the carotid artery.
Notice here, we'll place Doppler flow to confirm
the carotid artery shown here deeper to the
more superficial internal jugular vein.
In this patient, it would be extremely difficult
to cannulate the internal jugular vein
without puncturing the carotid artery.
Best to attempt cannulation in another area of the body.
One pearl that can be used to further distend the internal
jugular vein and make it a better target for a cannulation
attempt is to have the patient Valsalva or hum.
Notice here in the image to the left,
the patient is bearing down and notice that the
internal jugular vein becomes much bigger
as the patient pushes down.
In the image to the right, note the relatively small
caliber of the internal jugular vein.
Notice that it's almost as big here as the carotid artery,
but that it becomes much more distended
as the patient bears down.
Using the Valsalva technique can make it a much better
target for placement of the large cannulation needle.
Here's the high-frequency probe placed in a
longitudinal or long axis manner on the patient's neck.
Notice here that it's running along the course of the
internal jugular vein as it runs
up and down the patient's neck.
By convention here, I like to have the probe marker
towards the patient's head.
Therefore, I know where it lines up
on the ultrasound screen.
Notice here as a screen indicator dot is towards the left
that superior on the internal jugular vein
will be located towards the left of the screen
and inferior will be located
towards the right of the screen.
Here's a long axis view of an internal jugular vein.
I have the probe marker going more distally
or superior within the neck
so to the left is distal and to the right is proximal.
Notice the internal jugular vein that appears like
a tubular structure on the ultrasound screen
and we see the blood flowing here from left to right.
Here's a video clip, again a long axis configuration
in a different patient and here we see a much more
distended internal jugular vein that's lying on top
of the carotid artery.
Notice the swirls of blood in the internal jugular vein
showing the course of the blood flow
from high within the neck to the left,
low within the neck here to the right.
In conclusion, thanks for tuning in for part one
of Ultrasound Guided Central Venous Access.
I hope I've been able to score the point
that ultrasound is very helpful in determining
the relative anatomy of the internal jugular vein
and carotid artery prior to an invasive procedure
as a textbook anatomy of the vein to artery
is often incorrect and it's best to use a combination
of short and long axis views prior to a puncture attempt
to best define the anatomy.
So I hope to see you back in the future
as SonoAccess continues and we return
in central venous access part two.

Brightcove ID

5743132351001

https://youtube.com/watch?v=_RHRy64jQ6s

Case: Peripheral Venous Access - Part 2

Read more about Case: Peripheral Venous Access - Part 2

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Use ultrasound imaging to identify anatomy prior to intravenous catheter needle punctures, verify needle depth, and use dynamic techniques for attaining optimal needle guidance during deep vein cannulation & IV placement.

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- Hello, my name is Phil Perera
and I'm the emergency ultra sound coordinator
at the New York Presbyterian hospital in New York City
and welcome to SoundBytes Cases.
In this SoundBytes module, entitled Ultrasound Guided
Cannulation of Arm Veins Part 2,
we'll look further into the techniques needed
to use ultrasonography to guide a IV into
one of the deep arm veins.
As we discussed in part one of this module,
we first want to map out the vein using both short
and long axis views and we'll employ a dynamic technique
for optimal guidance for the catheter down to the vein.
Want to use a longer angiocath for the procedure,
preferably 1.88 inch or longer
as we need a good amount of plastic catheter in the vein
to avoid extravasation of fluids or meds
during resuscitation of the patient.
This recent published study showed that it's crucial
to select the correct target vessel when deciding
to cannulate a deep arm IV.
169 patients were enrolled in the study
and it was determined that the size of the vessel
directly correlated with the success rate
of the cannulation procedure.
A vessel with a diameter less than three millimeters
correlated to a success rate of only 56%.
While a diameter greater than 6 millimeters correlated
to success rate of 92%.
That's showing that the diameter was directly correlating
to the success rate of placement of a deep arm IV.
Also the depth of the vessel was very important
as no vessel that was deeper than 1.6 centimeters
was successful cannulated.
A very nice study by Dr. Panebianco et al.
A academic emergency medicine, 2009.
Armed with the knowledge of the last study,
here we're going to measure the diameter of a brachial vein
prior to a puncture attempt.
Notice here, we've selected a brachial vain
and we're measure the diameter at 3.7 millimeters
by 4.3 millimeters.
Thus, this would correlate with a low likelihood
of success rate during a cannulation attempt.
Notice also we're measuring the depth of the vessel
and while the depth of the vessel is six millimeters
less than the 1.6 centimeters that correlated
to no successful outcomes of peripheral IV cannulation,
the diameter of the vessel would be very difficult
to cannulate.
Now let's take a look at a better target.
This is a basilic vessel and we can see here
that the diameter is much larger than the last
brachial vein and we measure it at 6.5 millimeters
by 6.7 millimeters.
Thus, this would have a very high success rate
in terms of cannulation with a ultrasound guided IV.
We can also see that the vessel depth is relatively
superficial, again making it more amenable
to a cannulation attempt.
Once we have selected a favorable target vessel
for cannulation, we can place the probe in a short axis
of side to side orientation.
Here we're using a q-tip coming in underneath the probe
at 45 degree angle to look for the ring down artificat
for guidance for placement of the IV in a side to side
or lateral orientation on the patients arm.
We can look for a finding know as the ring down artifact
on the ultrasound screen as shown here.
Notice we have a nice plump basilic vein in the middle
of the field here and we can see a dark mark
emanating from the surface directly down.
Which is the ring down artifact caused by pressure
from the q-tip.
Thus this would be the appropriate poke point
on the side to side orientation on the patients arm
for placement of the IV.
We can also localize a vessel using the long axis technique.
Notice here we have the probe oriented
in an up and down configuration on the patients arm
and are placing the q-tip underneath the distal aspect
again at a 45 degree angle
to look for that ring down artifact onto the vessel.
To increase the accuracy of an ultrasound guided IV,
it's important to know the course of the vessel
as it runs up and down the arm.
Here we see in the picture to the left
that we're localizing the vessel at one point
on the patients arm but it's not enough
to know only one point.
We need to know the course of the vessel
as it runs up and down the arm as show in the picture
here to the right.
Notice we're marking two points on the vessel.
We have the distal poke point as noted by the blue x
towards the outer part of the patients arm
and then we're moving the probe more up the arm
more proximally to mark a second point on the vessel.
A line drawn between these marks would identify
the trajectory that the IV should follow
once it comes in at the the distal poke point
to successfully cannulate the vessel.
This longer angiocath at 1.88 inches would be more
optimal for cannulation of a deep arm vein
using ultrasound guidance.
This schematic shows the reason
that we need a longer angiocath when cannulating
a deeper arm vein.
While the vein my only be one centimeter deep to the skin.
Notice that the needle is not going directly down,
it comes in at about a 45 degree angle
to cannulate the vessel.
So we need a longer aspect of the needle just
to make it down to the target vein.
Plus we also need an ample amount of catheter
to be within the vessel lumen
to avoid extravasation of fluids or medications.
For this reason, 1.88 inch or longer is essential
for cannulation of a deep arm vein.
Now we're ready to cannulate a vessel
using ultrasound guidance.
We'll begin using the short axis or side to side orientation
of the probe with the probe maker
orientated towards the left
as we stand in front of the patient.
This will correlate with the ultrasound screen indicator
dot which is towards the left of the screen.
Generally I want to go and place the IV at a 45 degree angle
underneath the patients skin and then I'll place
the probe over the area of the IV to guide the IV
directly into the vein.
This phantom shows why using the short axis technique
can be an excellent starting point for guiding
the IV directly down to the vein under ultrasound guidance.
Here we can see a target vessel and note we see
the echogenic tip of the needle going
through the anterior wall of the vessel
and permeating into the vessel lumen.
So the short axis technique is optimal
for viewing lateral needle orientation
across the patients arm and guiding the IV directly
down into the venous lumen.
When using the short axis technique,
one must keep in mind the effect of probe slice
on visualization of the needle.
Note here, the probe is position more proximally
along the course of the needle and even though the needle
tip is securely within the vessel lumen,
we're only visualizing the needle to be above the vessel.
Notice the schematic view here towards the left
and we can see the probe is more proximal along
the course of the needle and the ultrasound view
towards the right and even thought the tip of the needle
is securely within the lumen of the vessel,
we're only visualizing the needle above the vein
and may get a false determination of where the tip
of the needle is.
Therefore, when using the short axis technique
when cannulating a deep arm vessel,
it's important to move the probe along the course
of the vessel to stay in plane with the tip
of the needle as you advance the needle under the skin
and into the vessel lumen.
Here we see we've moved the probe more distally along
the course of the vessel and now we're more
in plane with the tip of the needle.
We see the schematic view to left
and the ultrasound view towards the right
showing successful cannulation of the vessel
and the tip of the needle right within the vein lumen.
This video clip shows successful cannulation
of a brachial vein using the short axis technique.
Notice here we see the vessel and notice
we see the echogenic tip of the needle coming down
from the surface and permeating the anterior wall
of the vessel
and there we can see the echogenic tip of the needle
right within the vessel lumen.
We can also use the long axis configuration
for cannulation of a deep arm IV.
Optimally, you want to place the probe in the configuration
of the vessel as it runs up and down the patients arm.
By tradition, we want to have the probe marker oriented
distal so that the distal aspect of the probe
will line up to the left of the ultrasound screen,
as shown here.
So distal on the screen will be to the left
and proximal to the right.
The IV would then enter underneath the probe
at that 45 degree angle.
While the short axis configuration gives
a lot of information about side to side
or lateral orientation of the needle,
the long axis configuration gives a lot of information
with regard to vertical needle depth.
Here we see a needle coming from the left
and permeating into the vein lumen.
Notice here we can get an accurate determination
of the optimal depth of the needle
in relation to the venous lumen for cannulation
of the vessel.
Here's a real cannulation of a brachial vein
in a long axis configuration.
We see the vein stretching out in a long axis configuration
as a tubular structure running from left to right
along the screen and we see the needle coming
in from the left to the right moving up and down
and cannulating within the venous lumen.
So at this point, we're ready to thread the catheter.
This video clip captures a long axis cannualtion
of a deep arm vein and we can see the needle coming
in from left to right and we can see the needle tip
permeating through the vessel lumen.
Now we can see the actual threading of the plastic catheter.
So again we'll look at the needle coming in from left
to right and now we'll go ahead and freeze it
so we can see the actual plastic catheter
securely within the lumen of the vessel
and it's nice to visualize the catheter
within the vessel lumen to ensure
that there's enough catheter there to give a good amount
of medications and fluids with extravasation
of either of these liquids into the patients arm.
In conclusion, thanks for tuning in to this SoundBytes
module going over part 2 of ultrasound guided
cannulation of arm veins.
Ultrasound guidance for peripheral IV insertion
is an extremely helpful technique
and optimally you want to choose a target vessel
greater than six millimeter in diameter
and at a depth of less than 1.6 centimeters
to optimize our cannulation success.
We want also pick a longer catheter so we have
enough needle and plastic catheter to get into
these deep arm vessels.
We use a combination of short and long axis views
to dynamically guide the angiocath into the vein
and just bear with it because there is a steep learning
curve for these ultrasound guided IVs.
So you'll get it with time so don't give up
and practice practice practice.
So I hope to see you back in the future
as we SoundBytes continues.

Brightcove ID

5508134289001

https://youtube.com/watch?v=riizCYcXhRU

Case: Peripheral Venous Access - Part 1

Read more about Case: Peripheral Venous Access - Part 1

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Use ultrasound imaging to help identify deep and nonpalpable veins that can accommodate the placement of an IV catheter. Doppler color flow is used to differentiate the brachial artery from other anatomical structures.

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