Ultrasound Guidance

How To Perform A Saphenous Nerve Block

Read more about How To Perform A Saphenous Nerve Block

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Dr. David Auyong reviews scanning techniques and sonographic landmarks for an ultrasound guided nerve block.

Clinical Specialties

Anesthesiology (Regional)

Media Library Type

How To Videos

Subtitles

- The saphenous nerve block is useful for
medial knee surgery, medial leg surgery,
and medial ankle and foot surgery.
The saphenous nerve is a continuation
of the femoral nerve below the knee.
This is a good block to do in conjunction
with a popliteal sciatic nerve block to give you
complete anesthesia below the knee.
To perform the saphenous nerve block,
we typically use a linear probe.
The linear probe allows us to get
good resolution and reasonable penetration.
Typical settings for the saphenous nerve block
start between four and six centimeters total depth,
expecting the nerve to be between two and four centimeters.
Now the saphenous nerve is a small nerve,
and we may not see it in everybody.
In fact, most people we don't see it in.
The reason we do a saphenous nerve block
is that we don't take away any quadriceps muscles,
and so the patient will have no quadriceps muscle weakness.
To get a saphenous nerve, you may also do a femoral block,
but by doing a femoral block, you may
or you will take out all your quadriceps.
So this technique I'm going over is a great technique
for outpatient surgery, because their
quadriceps muscle strength will be intact.
This technique I'm using is useful in elderly
and obese patients because we're using muscle landmarks
rather than nerve or other small landmarks.
So we usually start about 10 centimeters above the knee.
Put the probe on the medial side of the leg.
We can abduct the leg a little bit
to give us better visualization here.
Now when we put the probe on here,
we like to start more anterior.
This gives us a view of the femur,
the hyperechoic stripe here, as well as the vastus medialis.
The vastus medialis can pretty much be found in everybody.
We're going to slide the probe posterior next.
The next muscle we'll come across is the sartorius muscle.
Now we see the vastus medialis muscle ending
and see the sartorius muscle in view now.
There are many anatomical differences in patient to patient.
The saphenous nerve can run anterior
to the sartorius muscle, posterior to the
sartorius muscle, and I've even seen it
piercing the sartorius muscle.
So the whole key is, is that we will put
our local anesthetic below the sartorius muscle
in order to get a good saphenous nerve block.
Most of the time we're doing a field type block
where we deposit the local behind the sartorius muscle,
and expect that that local will get to the nerve,
because these nerves can be difficult
to see in obese or elderly patients.
So now, our needle approach is
gonna be using a 10 centimeter needle.
This needle will be inserted a few centimeters
away from the probe in this angle.
We like to see the needle in a shallow plane
and then advance it deeper below the sartorius muscle.
This block can also be performed if the patient is prone,
imagine my needle coming from the other side.
Typical volumes used here are between
five and 20 milliliters of local anesthetic; if a good
nerve is seen, usually represented by a hyperechoic
structure, then I'll just place five milliliters.
Most patients, we do not see the individual
nerve here, and we will place 10 milliliters
as a type of field block in this area.
Here, our needle is advancing through the vastus medialis.
We try to position the tip of the needle
underneath the sartorius muscle,
which is located to the right of the screen.
You can see the hyperechoic areas,
some of which may represent the nerve.
Our needle is now directly below the sartorius muscle,
and you can see the local anesthetic
spreading below the sartorius muscle
to track to the saphenous nerve.

Brightcove ID

5508114742001

https://youtube.com/watch?v=E1tmS9Lv1bU

Body

Dr. David Auyong reviews scanning techniques and sonographic landmarks for an ultrasound guided nerve block.

How to: Subgluteal Sciatic Nerve Block

Read more about How to: Subgluteal Sciatic Nerve Block

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Dr. David Auyong reviews scanning techniques and sonographic landmarks for an ultrasound guided nerve block .

Clinical Specialties

Anesthesiology (Regional)

Media Library Type

How To Videos

Subtitles

- The Sciatic Nerve Block can be used for surgery of the
leg, knee, foot and ankle.
To do the Sciatic Nerve Block,
you can block it at the Popliteal region
or you can block it higher.
Some benefits of blocking it higher
are to be above the tourniquet,
so you don't have to worry so much about nerve ischemia.
You may also get the Posterior Femoral Cutaneous nerve
of the thigh, which comes off very high on the Sciatic nerve
and it's also medial to the Sciatic nerve, as well high up.
This way, you can cover any kind of pain of incision
in the upper thigh area.
To position patients for Subgluteal Sciatic Nerve Block,
we position the patient lateral.
This way, the patient is comfortable,
they can be well-sedated and you can place a probe
on the posterior side of the leg and advance the needle
from lateral to medial.
The probe we use for a Sciatic Nerve Block
is a curvilinear low-frequency probe.
The reason we use this probe is because
it penetrates deeper and this is useful in larger patients.
So some of the landmarks we use
for the Subgluteal Sciatic Nerve Block
are the Greater Trochanter laterally,
the Ischial Tuberosity medially, and
directly in between these two is where we place the probe
The initial view we see is the Greater Trochanter
on the left side of the screen.
On the right side of the screen,
we see the Ischial Tuberosity.
There is a large muscle, the Gluteus Maximus
at the superficial level of the screen.
Underneath the Gluteus Maximus is a hyperechoic nerve,
the Sciatic Nerve.
Between the two bony landmarks is the Quadratus Femoris.
So on this level, the nerve is sandwiched between
the Gluteus Maximus and the Quadratus Femoris.
The nerve here can appear wide, flat or triangular.
It is not a circular structure like some people imagine.
Needle approaches for the Sciatic Nerve Block,
whether is be here, at the Mid-Femoral region,
or higher up at the Subgluteal region,
are performed from a lateral-to-medial approach.
The lateral-to-medial approach usually starts
three to four centimeters away from the probe in this angle.
Now, higher up we'll use the same needle approach.
We can see the triangular Sciatic Nerve here,
and we'll start the needle angle about here.
Now you typically put my nerve
on the distal side of the screen from where my needle
is entering, in order to see the needle better
and travelling across the screen to the nerve.
Typical volumes are 20 to 30 milliliters
of local anesthetic.
Because this nerve is so deep in some people,
some anesthesiologists like to approach this nerve
from an Out-of-Plane needle angle.
And Out-of-Plane needle angle would be in this direction
into the Sciatic Nerve.
Other people like to turn this probe in a longitudinal
direction and see the nerve in long axis.
So here we are turning the probe in the long axis
and following that nerve in the longitudinal pattern here.
So now we see the Sciatic Nerve going down the leg.
The needle approach in this orientation would be in
this angle in plane of the ultrasound beam
down to the Sciatic nerve.
- (Dr. Auyong) Here you can see the Greater Trochanter
on the left side of the screen, the Ischial Tuberosity
on the right side of the screen, the Gluteus Maximus
superficial and a 21 gauge needle
advancing to the Sciatic Nerve.
The Sciatic Nerve is below the Gluteus Maximus
and above the Quadratus Femoris.
Our needle is advancing above the Sciatic Nerve
to attempt to get local anesthetic to spread
to the medial side of the nerve.
Which would be more likely to get the larger
Tibial component, as well as the posterior femoral
cutaneous nerve of the thigh.
Now you can see the nerve, which very hyperechoic,
below the local anesthetic.

Brightcove ID

5508120191001

https://youtube.com/watch?v=IL4qqETpb0k

Body

Dr. David Auyong reviews scanning techniques and sonographic landmarks for an ultrasound guided nerve block .

How To Perform A TAP Block With Ultrasound

Read more about How To Perform A TAP Block With Ultrasound

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Dr. David Auyong reviews scanning techniques and sonographic landmarks for an ultrasound guided TAP block.

Clinical Specialties

Anesthesiology (Regional)

Media Library Type

How To Videos

Subtitles

- The ilioinguinal and iliohypogastric nerve block,
is used for inguinal hernia repair,
and lower abdominal surgery.
This block is a field block,
where we put the local anesthestic within the plane,
between the transversis abdominis,
and the internal oblique muscle.
In order to find these landmarks,
we should position the patient properly,
we have the patient completely supine,
expose the iliac crest here
and the costal margin superiorly.
We use a linear probe for these blocks,
with a frequency of five to 10,
and have the frequency set
in the general or penetration mode.
Our initial probe placement is gonna be
just above the iliac crest.
I usually place the probe in this direction,
so we can see both the iliac crest caudally there,
and if I move slightly cranially,
you can see the three muscles of the abdominal wall.
Going from superior to inferior,
the first layer is Adipose Tissue,
the second layer is External Oblique,
the third layer is the Internal Oblique.
Now in some large patients, it's difficult to tell layers,
because their Adipose Tissue is quite significant.
So, a good clue is that, the Internal Oblique muscle layer
is going to be the thickest muscle layer.
Just as we see here.
The thin layer and the fourth layer down,
is a Transversus Abdominus muscle.
Below that is Bowel.
So that's very imporant to note,
that we are getting very close to Bowel,
and good needle visualization
is important for doing this block.
To actually do the block, I do turn my probe 90 degrees,
keeping those those planes on the picture.
And I still see the External Oblique, Internal Oblique,
and Transversus Abdominus deep.
My needle approach, is gonna be from anterior to posterior,
in this angle.
It's important to start several centimeters away
from the probe for this block, in order to see
the needle well.
If you start too close to the probe, such as here,
you'll have a sharper needle angle,
and you will not visualize your needle as well.
Flat needle angles, far away from the probe,
will allow you to visualize your needle.
Now I like to advance my needle in a shallow plane,
to view it first, and then advance it a little bit deeper.
I'm going to deposit local anesthetic
between 10 and 20 milliliters,
between the two deepest muscle layers,
the Internal Oblique, and the Transversus Abdominus.
In this image we can see the three layers of
the abdominal wall.
The External Oblique, the Internal Oblique
and the Transversus Abdominus.
Below the Transversus Abdominus is Bowel,
and you can see that moving.
So we wanna be very careful
not to advance our needle too deep.
Our goal is to inject between the Internal Oblique
and the Transversus Abdominus,
so we will carefully position our needle tip there,
and inject our local anesthetic.
For higher surgeries, you may want to perform
the same block higher.
Higher up, it's the same block,
using the same muscle planes, just given a different name.
Some people call this the Transversus Abdominus Plane Block,
or TAP Block.
Here now, we have moved just below the costal margin,
slightly cranially.
I will use the same needle position and advance it,
cranial to caudalal in this direction.
By moving higher up, we hope to get spread
a few dermatomes higher, potentially up to T7
with larger volumes.
The volumes I usually inject here are
10 to 20 milliliters on one side.
For bilateral blocks, for midline surgeries,
I'll stay on the same side, and just move my hands
over in this direction.
So I don't need to switch the machine to the other side.
I'll just lean over the patient,
get the same three muscle layers, and advance the needle
like this, in the middle of the probe,
just like previously.

Brightcove ID

5508104674001

https://youtube.com/watch?v=6E3ynIn6Ud4

Body

Dr. David Auyong reviews scanning techniques and sonographic landmarks for an ultrasound guided TAP block.

How to: Femoral Nerve Block

Read more about How to: Femoral Nerve Block

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Dr. David Auyong reviews scanning techniques and sonographic landmarks for an ultrasound guided nerve block .

Clinical Specialties

Anesthesiology (Regional)

Media Library Type

How To Videos

Subtitles

The femoral nerve block is used
for many different surgeries.
The femoral nerve block can be used for knee surgery,
hip surgery, femur surgery,
or even medial ankle surgery to get the saphenous nerve.
To perform the femoral nerve block,
there's a few key positioning tips.
We want to put the patient completely supine.
Many of our patients are larger and have larger abdomens,
so putting the patient supine allows us to get
high enough in the femoral region.
Also, if their adipose tissue hangs over the femoral region,
we want to put tape here and tape their abdomen away
out of the way, so you can put your probe
comfortably in the femoral region.
To do an ultrasound guided femoral nerve block,
we use a linear high frequency probe.
To start the femoral nerve block,
we usually put the probe right in the femoral crease.
On our screen now, we see several important features.
From medial to lateral, we see the Iliacus muscle,
we see the nerve sitting right on the Iliacus muscle,
and we also see the femoral artery,
and then to the right we see the femoral vein.
There are a few fascia coverings in this area
that are important.
The Facia Iliaca runs above the femoral nerve
and below the artery.
The Fascia Lata runs above all of this,
above the artery and vein as well.
Now for the femoral nerve, we want to see a hyperechoic
or bright nerve sitting on the Iliacus muscle.
The true femoral nerve is a wide, flat nerve
laying directly on the muscle.
If you inject above the Facia Iliaca,
this will create a barrier to your nerve
and allow a block that is not complete.
So as we move up and down the leg,
we're gonna see some key that will help you find
the femoral nerve in all patients.
More medially, you see the pulsating femoral artery,
and medial to that you see the femoral vein.
Here the vein collapses with pressure.
Now some keys to find the femoral nerve
in every patient are as follows.
If the probe is placed too cranially,
your femoral artery and vein and nerve
drop deep on the screen.
The femoral vein, artery, and nerve
are too deep, then you need to move the probe caudally.
If you probe is placed too distally,
that femoral artery is going to split
into two femoral arteries.
Here you can see a pulsating Profunda femoral deep
as well as a true femoral artery superficial.
Now I'm gonna put some color flow on that,
and you can see a pulsating artery deeper,
and a superficial femoral artery as well.
Now the vein is on the left,
represented in red in this picture.
As we move cranially, those two arteries come together.
When we look laterally from there,
the nerve has also come together from
many branches, forming one femoral nerve.
This way we can see the femoral nerve the best
when the artery also comes together as well.
Now our needle approach to the femoral nerve
is going to be from lateral to medial.
Typically, we use a 10-centimeter needle
because we use these in-plane approaches
to the femoral nerve.
I like to put my target on the further side of the screen
so I can see my needle coming in from the lateral side.
So I'll put my first injection lateral to the nerve
just above the Iliacus muscle
to ensure injection below the Fascia Iliaca
but not within the Iliacus muscle.
By using typical volume, such as 20 to 30 milliliters,
we'll get spread above the nerve
or below the nerve, without poking into
the nerve, and damaging the nerve.
In this femoral nerve block, you can see a single
injection needle being advanced lateral to the nerve
which is lying right on the Iliacus muscle.
You can see the pulsating femoral artery medially,
and the local anesthetic now spreading over
the wide, flat femoral nerve.
Our needle tracks in with the local anesthetic
so we can get local anesthetic spreading
all the way medial around the femoral nerve here.

Brightcove ID

5765925239001

https://youtube.com/watch?v=Z-O_EaAE_rg

Body

Dr. David Auyong reviews scanning techniques and sonographic landmarks for an ultrasound guided nerve block .

How to: Peripheral Arm Veins for Vascular Access

Read more about How to: Peripheral Arm Veins for Vascular Access

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An overview of ultrasound landmarks and scanning techniques used for peripheral arm vein access.

Applications

Cardiology

Clinical Specialties

Anesthesiology (Regional)

Media Library Type

How To Videos

Media Library Tag

Subtitles

- Ultrasound can be a great adjunct
for peripheral vein access.
Normally, our nurses can get pretty good access
to the peripheral vein through standard palpations,
but sometimes the patient may have an edematous arm,
their arm may be obese,
you may not be able to feel an antecubital vein easily.
In addition, if the antecubital veins cannot be accessed,
we may want to access deeper veins of the arm,
those being the basilic and brachial veins.
Ultrasound provides great visualization
of all of those veins.
We're gonna go ahead and choose the linear array transducer.
This is going to allow high-frequency imaging
to give us really good image quality
for superficial structures.
Remember, these veins are superficial
so we're gonna to want to get as good image as possible.
I'm gonna go ahead and choose the exam type.
Once I've chosen this transducer,
I do have different exam types I can choose from.
I'm gonna use the Exam button
to choose the Venous preset,
hit Select.
I've already got some gel at the antecubital fossa.
I already have a tourniquet up.
So let me now take a look at his antecubital fossa
and see what veins we can identify.
Here we have the transducer marker here,
I'm gonna put it to the patient's right.
Again, it doesn't really matter when we do vascular access
if it's to the right or left,
as long as the target vein is in the center.
First thing I notice is
that I can probably decrease my Depth a little bit.
So I'm going to go ahead and do that.
I'm going to turn my Gain up a little bit.
And I notice here, right in the center of the screen,
is an an anechoic structure, that is easily collapsible.
And as you can see, with simple pressure with my hand,
this vessel easily collapses.
There's no pulsatile motion and it easily collapses.
It is also quite superficial.
If you look at the marks here
on the right hand of the screen,
this is a half centimeter mark,
this is a one centimeter mark.
This vein is only about four to five millimeters deep.
So it'd be very easy to access.
If I'm looking at the screen right now,
and I put the vein directly in the center,
that vein will be directly in the center
of the transducer below the skin.
If you can not find anything in the antecubital veins,
you may want to take a look at the deeper veins of the arm.
So now let's take a look at the brachial
and the basilic veins.
I'm gonna put a little gel, a little more medial
of the elbow, and a little bit more proximal.
I'm gonna scan transversely across the arm.
I see a large vein,
here in the center of the screen,
which is collapsible.
In fact, I see multiple veins.
You can put a pretty large catheter into here.
You can easily place a 14 or a 16 gauge catheter.
I will recommend you use a two inch catheter
in all of these cannulations.
If you use a standard angiocath, you will get a flashback.
But unfortunately, most likely the catheter will dislodge.
So this, this is a good vein here.
If you look around a little bit more laterally,
we can see other veins,
and we can see the artery as well.
Here in the center of the screen,
you see a pulsatile structure, which represents the artery.
If you're unsure, if it's a very small vessel,
is arterial venous, you can put the color flow on.
And we see classic color flow profile
of an arterial structure.
So we're now scanning just above the antecubital fossa,
a little bit medially.
We have a pretty good image here,
just above the antecubital fossa, a little bit medially.
And we see a few structures here I want to point out.
We can see an artery, here in the center.
Again, when I put a little compression on it,
you can see pulsatile flow.
Adjacent to that,
you can see a vessel which easily collapses.
This represents a venous structure,
which could be cannulated,
but it doesn't look like it's in a great location
because it sits right adjacent to the artery.
In addition, on the other side of it,
is a slightly hypoechoic structure.
This represents a nerve.
So if I was choosing a location for venous access,
I would not choose this vein,
given the proximity both to the artery and the nerve.

Brightcove ID

5508134285001

https://youtube.com/watch?v=Pga4SAD-J9U