Transcript
- Welcome to the Sona site
behind the scan webinar called an Introduction.
Introduction to ves.
My name is Laura Jacob
and I will be moderating moderating today's webinar.
Before we begin, please be advised all attendees are muted.
You may type your questions into the q
and a box in the toolbar located at the bottom
of your screen at any time.
We will conduct a q and a session at the end
of the presentation.
This webinar will be recorded
and archived for future reference on our webinar's website.
Here with us today we have Dr. Katie WIS Carr. Dr.
WIS Carr is a general internist at Vancouver
General Hospital.
She completed her core internal medicine
and general internal medicine fellowship at the
University of British Columbia.
She completed a year of POCUS fellowship including six
months of critical care ultrasound fellowship at Western
University in London, Ontario.
Her POCUS passions include VES
and pocus, evaluation of volume status,
all things echocardiography
and clinical integration
of ultrasound findings outside of medicine.
You can find her on the beach volleyball court,
hiking in the mountains, or playing with her two sons.
And with that Dr. Wiska, I will turn it over to you.
- Great, thank you so much Laura.
And thank you guys for joining me here today.
I'm really thrilled to be talking today about a topic
that is very near and dear to my heart.
So without further ado, today, our objectives are one
to talk about how to perform AveXis exam,
which is a venous excess ultrasound exam to understand how
to interpret the waveforms that comprise axis exam.
We'll talk a little bit about caveats and pitfalls
and then we'll go through a couple examples of
how this can be integrated into your
clinical decision making.
So to start off with, what is venous congestion
and why do we care about it?
Why is it so important?
So for a long time when we talked about organ perfusion,
we talked a lot about the left side, the arterial side,
about cardiac output, about mean arterial pressure.
But increasingly we're coming to realize the importance
of the venous side.
After all, when we talk about organ perfusion,
tissue perfusion is gonna be your map minus your CVP
and especially as we talk about the capillary beds
where arterial pressures are actually very low,
CDP becomes a really important force for organ perfusion.
So we're increasingly recognizing
that venous congestion is critical for organ perfusions,
and almost every organ in the body can mean negatively
affected by venous congestion,
by excess fluid and fluid overload.
So the, the most common
and well-recognized example here is
obviously pulmonary edema in the lungs,
but this can affect the whole body.
So cerebral edema in the brain, congestive nephropathy,
congestive hepatopathy, gut edema, tissue edema
and poor wound healing, the list goes on.
So this is something that we really wanna recognize
and try to address if it's present.
Now, part of the reason why this was under-recognized for
so long is we haven't always had great tools
to assess the venous side.
We've had, you know, CVP monitors or swan gans catheters,
but obviously those aren't accessible in all patients.
You know, we have a physical exam,
but as I'm sure most of you recognize, staring at the neck,
veins is far from a perfect technique
and even with ultrasound.
So when the IVC came around, this was kind of heralded
as the answer to volume status questions, which it is not.
It can certainly be useful
but is not as specific as we would like for volume overload
and can be confounded by other things.
And even as we talk about lung ultrasound,
and I'm a huge proponent of lung ultrasound,
but lung ultrasound tells us about, you know,
the left side congestion in the lungs, kind
of backing up from the left side of the heart,
but doesn't really tell us about what's going on in the rest
of this, the systemic circulation, kind
of the right side, the venous system.
So enter xxi.
So as I said, VAXIS stands
for the venous XXI ultrasound grading system.
So this was an idea put forth in a paper just a couple years
ago by William Boian Solani and his colleagues.
And what they did is they essentially built on the notion
that intraabdominal vessels,
so in particular the hepatic vein, the portal vein
and the intrarenal veins all have
predictable doppler waveform.
So when we interrogate them with doppler, they have
a set waveform under normal physiologic circumstances.
And these, those waveforms will predictably change
with increase in congestion.
Now it was not new
and each of those waveforms had literature
behind it going back years, sometimes decades,
primarily in heart failure populations, caral,
renal disease, et cetera.
But what this group did that was novel is they suggested a,
a combined sort of scoring system combining these three
waveforms to try to, you know, develop a metric
that was more sensitive, more specific
for harmful venous congestion.
And they look specifically at a post cardiac
surgery population.
And their outcome that they was in,
that they were interested in was the development
of acute kidney injury.
So this is just a graph from that paper again and again.
The whole premise here is that each of these vessels,
the hepatic vein, the portal vein
and the intrarenal vein all have waveforms under normal
physiologic conditions.
And you can see that these change
with increasing right atrial pressure, increasing congestion
and we'll go, we'll talk a bit more through kind
of interpreting these waveforms.
This is kind of a, a busy slide from the paper.
The important part here is kind of this,
this circled xis C column in the middle.
So what this group did in their paper is they proposed
several sort of combinations of scoring systems
and they tried to validate in their population which
of them had the best predictive value,
the best predictive capabilities for a KI.
And what they found is that this vex is C
grading performed the best.
So this is the one that you wanna remember.
This is the one that we use now in ultrasound practice.
And as you can see here, the IVC is kind
of like your gatekeeper.
So if you have an IDC that is small
and collapsible that you are are sure of is a good tracing,
you know, do not pass go do not collect $200 you,
you don't have significant venous congestion.
In contrast, if you have severe abnormalities in multiple
wave forms, then you're more likely
to have severe congestion
and that's associated in this study with a higher incidence
of the development of acute kidney injury.
And their hazard ratio here was just under three.
Now this is a pretty recent paper so the evidence for this
and kind of using the scoring system is still in evolution.
But there have been a couple groups who've looked at this.
One group looked particularly at all
of the individual components.
They interestingly found that the
hepatic vein was the most predictive.
That was Spiegel Roy Spiegel and his colleagues.
And then a recent paper in the Indian Journal
of Critical Care looked to validate the VES score
and again found that a high vexa grade was predictive
of acute kidney injury.
And these were patients admitted with cardiorenal syndrome.
And as I said before, each
of the individual waveform components do have some,
in some cases decades
of supporting evidence in particular populations,
usually the heart failure population.
And just to speak to that, so this is a paper from 2016
by 10 etal and was actually speaking primarily
to intrarenal venous patterns.
But this is a really nice graph just to show once again
that these different vessels all have predictable changes in
their doppler waveforms with increasing congestion.
You see the renal artery included here,
we're not really gonna talk about that today as
that is an included infectious protocol.
But that vessel also does have kind
of changes with congestion.
Here we just see the inferior vena cava
and again, we won't really talk about tissue doppler
and kind of tricuspid inflows here.
So with that all being said, how do we actually do this?
So to start off with the IVC is part of the vest exam.
So you're always gonna wanna get your IVC first
and I won't really belabor how to do this.
Most of you I'm sure are familiar with how
to obtain an IVC view.
I will just say that in addition
to your standard long axis IVC view
where you see the right atrium, the hepatic vein,
a nice segment of the intra hepatic IVC,
I'd really encourage you to try
to get a short access view of the IVC.
And what this does is this kind
of corroborates your findings
and help you avoid some common pitfalls of the IVC
one common pitfall is
that occasionally we can get significant lateral translation
of the IVC with respiration.
So in a long axis you may think you're seeing collapse,
but we're actually just getting the IVC move laterally out
of your plane with respiration.
So a short axis helps avoid that pitfall.
It also gives you a better idea of the shape of the IVC
and we'll talk about about this a bit more about this later.
To obtain a short axis
of course all you're gonna do is rotate your probe 90
degrees from your long axis view
and you can do this with either your curvilinear
or your phased rate probes.
Moving on to the hepatic vein.
So I used to acquire the hepatic vein as you seen here,
as you see here on screen right from a sub-I foot approach
because you'll usually notice as you go
to get your long axis IVC view that
of course you see the hepatic vein coming off
of it and that's not wrong at all.
You can totally interrogate it from this view.
I tend now more to favor as you see here on screen left.
So a lateral approach, kind
of trans hepatically scanning in a Corona plane just
because I find that this view gives a nicer doppler waveform
because the orientation of the veins with respect
to your probe is optimized.
But wherever you're gonna go again here you can use a phased
array probe or a curvilinear probe.
I tend to use a curvilinear probe just
because it's gated a bit better for these low velocities.
The biggest advantage of the of the phased if you want to is
that if you have it available you can attach a CG gating.
But wherever you are, you're gonna identify your hepatic
vein and then you're gonna use color
to make sure you have good signal in your vessels.
Once you have that, you're gonna use pulse wave doppler.
Place your doppler gate right in the middle of your vessel
and obtain your waveform here.
And what you should see is a nice normal hepatic vein
waveform that has technically four components, your A
and v waves above the baseline and your s and d waves below.
Really we're gonna pay attention to the s
and d wave seen in systole and diastole respectively.
And as a warning, your waveforms will never look this nice.
This is like the nicest waveform I've ever
gotten on a hepatic vein.
Normally they're a bit messier than this.
Moving on to the portal vein.
So here again you can obtain this scanning sort
of subcostal along the costal margin along the belly,
but I find it much easier from a lateral approach in a
coronal plane, usually here a little bit of fanning,
a little bit of sliding your probe inferiorly.
We'll easily identify the portal vein
and you'll be able to identify it
because it's bordered
by this bright hyper coic fat with thick walls.
And when you put color on, you'll see this nice red heed
flow so flowing towards the probe.
So once again, once you've got your vessel identified
with color, you're gonna use pulse wave doppler
and identify this nice continuous sort of resate
with some gentle phasic undulations.
You may have to identi who to adjust.
So your baseline and your scale here.
But this flow above the baseline
is what we're looking for here.
There's a bit of noise under the baseline here,
but this is what we're after this normal
continuous low grade flow.
Finally, in terms of acquisition,
we'll talk about the intrarenal veins.
So here once again, we're gonna find the kidneys in the
usual manner, scanning in the flank in a coronal plane here.
Color of course is key
because these vessels are so small that they're not
otherwise visible.
And once you have ideally a good color tracing, making sure
that your quis limit is AP turned down appropriately low
because this is very low velocity flow here.
And I should say you can actually use color power doppler
and sometimes I will do that instead
of normal color doppler just to get that low velocity flow.
And then you're gonna try to interrogate a vessel
that's in the renal cortex
or at the cortico medullary junction.
You wanna try to avoid the vessels
that are in the renal pelvis
as those will be affected by other factors.
So you're going for sort of the that cortex
or the cortico medullary junction.
You'll drop your pulse wave doppler again
and obtain a tracing that looks something like this.
Again, adjusting your scale and your baseline appropriately.
And the flow that we're interested in is this continuous low
grade flow below the baseline.
Now you'll see that above the baseline we have a tracing
that looks arterial
because that's our renal, an intrarenal artery.
It's quite normal to catch both
of these on the same waveform as these vessels are paired.
So travel together. But what we're interested in
for our purposes in the VE in the Xis exam is this low grade
flow beneath the baseline here
that is continuous under normal physiologic conditions.
Again, I would recommend doing all of these, the hepatic,
the portal, and the intrarenal vein.
Typically with a curve linear probe, you can use the phase
as I've done here, but I find the curve linear gives you
slightly better resolution
and is better gated for these low velocities.
Alright, so we'll talk a bit now about interpretation.
So obviously with your IVC under normal circumstances
what you're looking for is a collapsible kind of oval,
ellipsoid shaped IVC.
And again the short X is a really nice check to make sure
what you're seeing is true collapse rather than just
lateral translation.
It also gives you a much better idea of the shape
because we know that under normal physiologic conditions,
the IVC is oval shape.
So depending on where you're cutting it,
you may actually measure say 2.1 centimeters,
but you may actually have an IVC that is not kind
of really plethoric.
So in the xis criteria they did use a
cutoff of two centimeters.
However, I know
because I've talked to Philippe Rola who's one
of the authors several times about this, their,
their group feels that the,
the more important criteria is really sort of plethora
and shape of the IBC.
They use the two centimeter cutoff in the long axis
'cause that's what's available was available in their data.
But really more important is to try to get a sense
of the shape of the IVC and how plethoric
and non varying it is rather than paying too much attention
to an absolute number cutoff.
So contrast these IVCs with here you can see an IVC
that is clearly plethoric is clearly non varying
and in the short axis you can see it is very
round and spherical.
So that is really suggestive of an IBC in the setting
of elevated ral pressures.
So if you have a large IBC like this a plethoric IBC,
you'll continue and do the rest of your VES exam
in terms of interpreting the hepatic vein.
So under normal physiologic conditions, most
of your flow's been below the baseline here
and you should have your S wave being greater than your G
wave or here they're kind of just about the same.
But under normal conditions, again,
if we go over one we probably have S and then D.
Sometimes in tachycardia they may fuse slightly together,
but you should see your S wave being the
predominant component here.
In contrast, as we progress through increasing congestion,
the first thing you'll get will be your D-Wave becoming
greater in amplitude than your S wave.
And finally, in settings of severe congestion you'll
actually see reversal of the S wave above the baseline.
Now this occurs almost always in the setting
of some tricuspid regurgitation
because your tri, your TR jet is going
to be what's responsible for that backflow
of blood back up the hepatic vein up towards the probe in
systole when normally blood should be flowing down
through the hepatic vein towards the heart.
Now theoretically you can get a reversed S wave in the
absence of TR under certain conditions such
as severe artery dysfunction, heart block,
very prolonged PR interval, et cetera.
Practically, I don't know if I've ever seen that.
It's almost always in the setting of at least sort of mild
to moderate tr where you're getting this
S wave reversal here.
Moving on to interpreting the portal vein.
So as I said, normal should be a continuous low grade flow
with some spiro phasic variation less than 30% ity.
So ity we're talking about our maximum minus our minimum.
In contrast, as you progress
through at first mild congestion
and then severe congestion, you're going
to get increasing ity.
So mild congestion is 30 to 50%
and the image I put here on the left is actually a bit
misleading because this is clearly almost a
hundred percent congestion.
So this scan would be consistent with severe congestion.
Here on the right we have very severe congestion
where we actually have some reversal
of flow below the baseline.
So clearly more than 50% ity,
very severe congestion probably also occurring in the
setting of tricuspid regurgitation,
finally interpreting the intrarenal veins.
So once again, normal flow should be continuous
below the baseline with really minimal variation.
As you progress through mild congestion,
you'll see a biphasic pattern appears
so distinct waves in systole S here and diastole.
And finally in very severe congestion you'll get monophasic
flow in diastole only.
So a few pitfalls and caveats.
So first some technical things.
The hepatic vein can be quite difficult
to interpret without ECG.
This is an example here where it's a little bit difficult
to tell what's going on.
This here might be an S wave,
this might be a D-Wave here we maybe have S reversal,
but without ECG leads this can get quite tricky.
So I would encourage you, especially as you're learning
and practicing, if you have ECG leads at your disposal
to go ahead and hook those up,
especially in tachycardic patients,
it can get quite challenging.
Next you will see respiratory translation of these vessels
because they're quite small targets, especially in patients
who may be hypoxic or or struggling to breathe.
You can see quite significant respiratory translation
of the intraabdominal organs
and you can see here this waveform is kind of coming in
and out of view making it a bit difficult to determine
what sort of the maximal and minimal points here.
This is a portal vein tracing.
So if your patient is able asking, asking them
to hold their breath is really useful, especially
for your intravenous vessels.
And really the kidneys are extremely challenging,
definitely good to practice.
But I will say that in the patient's eye scan, probably 30%
of the time I get a really good intrarenal vein
tracing that I'm confident in.
So don't feel bad if you find that exam very difficult.
Everyone I've talked to including people
who use this on a daily basis do find that challenging
and that's often, often just a product of the patients
who we are scanning in hospital,
most patients are acutely unwell, may have tissue edema,
may have other factors that make it challenging.
A few other things to note.
So as we went through briefly initially, the evidence
behind this is growing but thus far is you know, limited
to specific patient populations.
I don't think that's a reason not to use these techniques
because the alternative, the alternatives for, you know,
assessing venous congestion right-sided congestion
are not great and also don't have a lot
of great evidence to support them.
But just something to keep in mind
as the evidence base evolves.
It's also worth saying that there are other pathologies
that can affect each of these waveforms
and that's part of why it's really nice to try
to do the entire VES exam
and to try to take each of these waveforms
and combine the data for them
because that, you know,
somewhat eliminates potential errors if one waveform say may
be affected by cirrhosis, for example, affecting the hepatic
and portal veins or increased intraabdominal pressure
or intrinsic renal disease are common things
that can affect those waveforms.
Whereas if you have three waveforms
that all look like congestion,
that paints a stronger picture in favor of you know,
that clinical conclusion of elevated right-sided pressures.
Finally, super important with any ultrasound talk is
to always interpret your ultrasound findings in the context
of the entire clinical picture.
This is one data point.
You should never base decisions on a single data point, try
to avoid the quote unquote vs.
Lasix or vs Furosemide reflux.
Firstly, again because you wanna take the entire clinical
picture into consideration and also
because you know, findings
of increased congestion typically should be addressed,
but diuresis is not the only way to do so.
So for example, if you have a patient
with significant right-sided failure, another way
to address their systemic congestion may be you know,
to adjust their mechanical ventilation settings if they're
intubated or inhaled pulmonary vasodilators, et cetera.
So make sure you're still considering the entire clinical
picture and consider that the goal for everyone is not
to live at AveXis zero, especially in patients
with concomitant heart failure,
right heart failure, left heart failure.
For some people they may not be able to live
with a small collapsible IVC
and they may always live with some degree
of elevated right atrial pressure in sort
of their compensated state.
So keep that in mind that you know,
this is not a cookie cutter approach
and has to be individualized to the patient in front of you.
Finally, a few practical tips I think
I've addressed most of these.
Breath holding in PA in cooperative patients is really
helpful, especially for your renals.
ECG leads are helpful if they're available.
And finally, I know I said try
to look at everything if available and absolutely do,
but if you can only get one waveform,
the portal vein can be useful.
And I do use this sometimes in patients in whom their
hepatic is too hard to interpret,
their kidneys are not obtainable.
The portal vein is typically the easiest to obtain,
is the most reliable to interpret
and does kind of change more readily than the hepatic vein.
You will have patients and we'll see in our example case
shortly, you'll have patients in whom their hepatic vein
will always be abnormal, especially if they have moderate
to severe tricuspid regurgitation just
because the hepatic vein is so close to that right atrium
so close to that backflow of tr
so their waveform may never normalize
where whereas the portal vein with a bit more distance
will better show sort of changes with diuresis or or
or excess fluid if you're going in the wrong direction.
So the portal vein can in and of itself be quite useful.
Alright, all right, going forward
and putting everything together, we're gonna go
through just a couple cases here.
This first case is with a young gen young gentleman
with a hematologic malignancy on chemotherapy who'd had a
lot of infectious complications,
what had been quite stable on the ward
and then sort of rapidly overnight developed new
hypoxia and hypotension.
So our ultrasound team was asked to come assess him.
I won't show you his whole lung scan as
that's obviously not the focus of today,
but suffice it to say that his entire lungs essentially
looked like this with a few sort of spared areas of a lines
but predominantly a B-line pattern throughout his lungs.
Again, I won't show his whole cardiac exam
but this was a surprising and new finding.
He previously had a normal echo from less than a year ago,
but here we see obviously decreased ejection fraction
that again was new for this patient.
So we looked at his IVC
and it does look quite collapsible here.
We wanted to be sure of our findings in this case
because this was a young gentleman
who was taking very big breasts,
obviously exerting significant respiratory efforts,
significant sort of press intrathoracic pressure changes.
So we wanted to be sure that these findings weren't a
lateral translation or just an effect
of his substantial work of breathing.
So his short axis is, you know,
again reassuring it does look fairly ellipsoid in shape
but we did go ahead and just check his hepatic vein
and this was quite reassuring.
So here we see an s
and d pattern, essentially the same size, so consistent
with likely a normal state, perhaps very,
very mild congestion if you thought that dway was bigger.
But overall very reassuring.
So here, even with just these findings,
we were confident enough to say that despite the findings
of new decreased ejection fraction
and diffuse beelines in this patient,
that his new hypoxia was probably not predominantly from
pulmonary edema and that this seemed more likely to be
an evolving A RDS, an infectious picture, et cetera,
based on the fact that there really wasn't any evidence of,
you know, venous congestion.
His lung findings as I said,
also did demonstrate skipped areas which would be less in
keeping obviously with pulmonary edema.
Next, moving on to case number two.
So this was a 7-year-old woman with known heart failure,
coronary disease, AFib
and ovarian cancer thought to be in remission
who'd recently had several admissions
for acute kidney injury including one
where she was transiently on hemodialysis
and that was thought to maybe have been a pre-renal insult
progressing into a TN
and she came in again with new ascites of unclear etiology
and another acute kidney injury
and she was a really difficult clinical volume status
and everyone was very hesitant to diurese this woman given
that she just had these AKIs including one severe enough
to land her on dialysis.
So she sort of got handed off between staff over a weekend,
you know, someone would try a little bit
of diuresis then she'd get fluid again
and it was really unclear from sort
of traditional physical exam parameters.
What was going on with her, her volume status
and what was the cause of her a KI.
So this is her cardiac scan here.
This is not a surprise
but severely reduced left ventricular ejection fraction.
You also get a sense of some abnormal septal movement here
hinting at what we see in this apical four chamber view,
which is a dilated RV
and significant RV dysfunction as well.
And I don't have color on this
but you can probably imagine
that she had quite significant tr,
you can see those trias valve leaf,
let's just barely co-opting there.
So this was her IVC.
This image sort of fanned through the IVC
to look at the hepatic vein.
So not ideal for assessing the spiro phasic change,
but you can appreciate that it looks fairly plethoric
and also that the hepatic vein
is quite plethoric and visible.
You'll notice as you start doing this exam
that in normal people who do not have venous congestion,
the hepatic vein can actually be somewhat hard to find
just 'cause it's so small.
Whereas if you see a big juicy plump looking hepatic vein,
you're probably dealing with at least mild congestion.
So this was her hepatic vein tracing.
So again, a really prominent sort of biphasic pattern
where you have reversal of the S wave.
And what we actually have here is fu, sorry, fusion
of her SA and V waves above the baseline.
So again, consistent with her severe tr
and this was actually then her portal vein.
So here once again consistent with very severe congestion
as we can see actual reversal of flow
below the baseline reminder that the portal vein is supposed
to be continuous low grade above the baseline.
So this gave us enough sort of courage
to aggressively diuresis woman
who you know had just been in dialysis
who everyone thought had a susceptibility to proving AKIs,
who had a very unclear kind of clinical story, gave us kind
of the the mental fortitude to aggressively die research.
And she actually did very well with that.
Her creatinine came down back
to its baseline over about a week.
We also thought that given this picture her ascites were
more likely to be in keeping with heart failure as opposed
to, you know, a new ovarian
or recurrence of her ovarian cancer.
She did of course also get a paracentesis with diagnostic
diagnostic sent on her acidic fluid,
which again we're consistent with this being more
of a heart failure picture rather than malignancy related
and her cytology was negative, et cetera.
But this is her discharge exam.
So this is her hepatic vein
and you can see that this hasn't really changed very much
as I was saying before, especially in patients
with severe tr,
their hepatic veins probably will never normalize just
because they're so close to that backflow from the tr.
But in this case here, this is her portal vein,
so still abnormal certainly but better than it was before
and she's probably a patient
who will never live in veis zero given her
right and left heart disease.
But this was certainly an improvement clinically,
she was back at her baseline,
her creatin was at at baseline, she felt very well.
So this may be her normal.
Unfortunately I don't have kind of an outpatient VE xxi
that's sort of the next step is to get everyone
to VE access in their clinics.
So we have documented outpatient veis on everyone,
but this was really useful in this patient both
for monitoring her therapy as well as for kind of
that diagnostic picture of is of is this preen
or is this congestive nephropathy?
All right, I think that's all I have so I'd be happy
to take any questions.
Thanks.
- Thank you Dr. Skar for an excellent presentation.
And we will go ahead now and take some questions.
Feel free to type your questions into the q and a box
and I will just give it a moment
as we're waiting for questions.
You can see on the slide here, this shows the website for
where we house our recordings of our webinars
and any upcoming webinars as well.
This is also a really good resource for you
to contact us directly.
I'm waiting for questions here. Dr.
Skar, can you, this is from me actually,
can you speak a little bit more about the whole
outpatient ves?
Sounds like that might be a barrier that you're exp
that that exists.
- Well, I mean I think that especially in the patients
that we see in hospital, as I said, a lot of them have
underlying heart disease underlying sort of pathology such
that they probably don't live at VEXA zero.
So it's always this question of like what is their baseline,
- Right?
- So you know, if we see someone
with an abnormal portal vein
or abnormal renal vein, we don't know if
that is their normal or if that is abnormal for them.
So in an ideal world, you know, we'd have a,
a follow-up clinic maybe where we'd see these people
after discharge and document their, their VEX exam sort
of at their dry weight.
We don't yet have this at our hospital a
because I practice almost all all inpatient medicine
and we don't have, we don't have the
equipment in our outpatient clinic.
We don't have access to doppler ultrasound,
but I know, I know some people, so some people
who are very prolific with VES on Twitter, for example,
a very prominent ultrasound nephrologist who many
of you may know who has excellent VES resources,
but he'll often post sort of follow ups from, you know,
clinic to hospital.
And that comparison point is really useful,
especially in these complicated patients.
- Right, absolutely. Okay,
I am not seeing any questions
so I just wanna take another moment to say thank you Dr.
Wis Carr for taking the time
to put together this excellent presentation for our webinar.
We really appreciate you sharing your expertise
with our audience and thank you to everyone for joining us.
Oh, looks like, oh we did get two questions popped up just
as I was saying that okay, for portal vein interpretation,
can you explain what you mean by pulse utility
and how that is estimated?
- Yes, of course. So ity, what we're looking
for is, is the variation.
So you can either measure this
with calipers or you can eyeball it.
I almost always now will sort of eyeball this.
But what you're looking for is the variation
between maximum,
it's maximum amplitude and minimum amplitude.
And if you were actually most machines,
if you use your calipers and mark your maximum amplitude
and your minimum amplitude,
the machine itself will spit out a
pulsatility index for you.
But the formula is basically max minus min over max
gives you your pulsatility index.
So again, you're looking for kind of
how much does that vary?
- Okay, thank you.
Are you aware of any studies showing the same findings
outside of the post-op cardiac patient?
- Yeah, so I, as I said, there was this one study recently
in the Indian Journal of Critical Care Medicine I think
that looked at an ICU population admitted
with cardiorenal syndrome
and they looked specifically at the VEXA score
and did find an association with a KI in that population.
And then Roy Spiegel and colleagues had looked at the
waveforms individually in a general ICU population
but didn't I think look at the kind
of the summation of the score.
So I think when I had last looked, that's what's out there.
I'm sure that this evidence,
as I said will continue to evolve.
I think Philipp Rola and his group has something else
cooking probably and William Boba Solani.
So I think we'll start to see this more
in different populations.
- Okay. And a follow up questions from the same person.
What about new hospitalizations coming out of the ed?
- Oh, in terms of
- What, yeah, what's the question here?
Let's see, JM,
if you can type in a little additional part of your question
that would be helpful here.
So the first question was just
what you just answered showing the same findings outside
of the post-op cardiac patient.
So maybe this is, what about
outside new hospitalizations coming out of the ed?
- Oh, in terms of evidence for
- In term, oh he just responded in
terms of fluid administration,
- What message for new admin admit patients and monitoring?
Yes, so I mean I, I guess just in terms
of the general application of axis,
I certainly use this in in people coming outta the i
the emerge.
So I practice general internal medicine almost
exclusively inpatient.
So we see this, you know,
we see people in whom VES is useful a ton.
The primary population in whom I find this useful
is the cardiorenal people.
So on the wards that's where I find this the most useful.
So those people who do have heart disease who maybe have CKD
and everyone's wondering are they,
do they have congestive nephropathy or are they pre-renal?
And I find the instinct still among, among my peers,
among trainees is when people have an a KI
to hold diuretics.
And often that's exactly the wrong thing to do,
especially in people with right heart failure.
I see a question here about pulmonary hypertension,
but especially in those patients often it is much more
of a congestive picture rather than a pre-renal picture.
So this, that's the population in whom I use this most
on the wards is that kind of cardiorenal population.
- Okay, great. So it looks like you answered
that question about pulmonary hypertension.
- Yeah, I, I guess the other,
the only other caveat is the in the pulmonary hypertension
people, that's kind of a prime example
of people in whom they probably will never
live at vexa zero, right?
They're always gonna have some degree of elevated
right atrial pressure and CVP
and trying to dire them to the point
of AveXis is probably harmful in those PA patients.
What I, the, the kind of scan that I will also often add is
to try to look at their cardiac output as well in anyone
with sort of underlying heart disease to try to get a sense
as we're diuresing them, if I'm over diuresing them
to the point that they're now not getting enough forward
flow that's useful.
And again, ideally you have like an outpatient baseline
and you could say like, oh this is their portal vein when
they're, you know, at their dry weight
and compensated that would be the dream.
- Right. Understood. Okay.
And we have a quite of a, a long question here,
so I'll do my best here person.
Nick says, I'm in the midst of trying to set up a project
to validate vex and pediatrics.
One thing I've had difficulty deciding on is what to do
with IVC as a gatekeeper completing the remainder
of the exam as you,
as you've said in the literature supports IVC size
but informally there are other IVC characteristics
that are important and then even in the setting
of a normal appearing IVCU can have abnormal signals in
other VA visceral vascular beds,
but it makes it hard to decide what to do with
that in literature supportive mater manner interested.
- Yeah. Yeah, no that's a really good question
and I know as I said from talking to, that's awesome
that you're trying to do a project of vessy in pediatrics
by the way, like super cool,
I can't just see what you come up with.
I know informally, like in talking to Philippe Rola that
you know, the finding he feels is most important
and this is kind of what I've come to in my practice
as well is sort of more the shape of the IVC.
So, so how spherical it is,
there is some evidence to support this.
So as a study in I think 3D transesophageal echocardiography
actually, but I mean I have no reason why this wouldn't also
apply but that it basically showed that ity of the IVC.
So how round it looks was a better predictor was was more
correlated to CVP than other measures of either IVC size
or IVC collapsibility.
So there is some evidence there for kind of that aspect
in terms of having a normal IVC
and then abnormal signals in other vascular beds.
I think then you'd be invoking sort of, you know,
organ specific dysfunction.
I think if you're talking about systemic right-sided venous
congestion outside of you know, some sort
of int hepatic pathology that's compressing the IVC or
or tumor or that kind of thing,
you really should have a plethoric IVC if you're invoking
end organ congestion in the liver
and kidneys would be my take.
- Okay, great. Thank you for all those comments. That helps.
And then we have kind of a two part question.
Can this be utilized to evaluate fluid resuscitation in
sepsis IE to make sure we haven't over resuscitated?
- Yeah, I think this is definitely,
this is definitely something that I have done
and seen in practice
to my knowledge the the evidence is not here yet.
But again, not to say that this is not useful.
I think this totally makes sense.
I know especially my critical care colleagues
and my emergency medicine co medicine colleagues
who practice this exam find this
to be a really useful finding.
'cause again, it's just a bit more sensitive, right?
Like I think the old practice used to be like,
give them fluids until, until you have to intubate them,
which is not great and then, you know,
give them fluid till you see beelines
and this is even an earlier stop point than that, you know,
to, to try to resuscitate until you start to see evidence of
that right-sided venous congestion.
So I think that's an excellent, that use of this, again,
once you get pretty good at this exam,
especially if you're just maybe say following the portal
vein over the course of a resuscitation,
that's quite a quick exam and quite easy to do.
So I think that's a great use for this
and hopefully in future we'll start see evidence in
that specific population as well.
- Okay, great. And what would,
what might be the best approach for learning this technique
before getting to the point of practicing scanning?
- So, you know, I think that this is something
where there's a lot of free open access educational
resources out there.
So you know, obviously through SonoSite
and this webinar there are on Twitter,
I'm gonna say nephro pocus, if you ne pocus,
if you don't follow him you should,
he has like a tagged tweet
or a pin tweet that has a whole list that he updates
of like VEX resources.
That's excellent. And so there's some screencasts,
there's Twitter threads, there's a whole thing I,
you know, shameless self-promotion.
I have a Screencast
that's on my UBC Im POCUS website that talks about ves.
So there's a lot of stuff out there.
There's often a lot of discussion on Twitter if you pay
attention to sort of the vex obsessed
crowd that is great for learning.
And then just go and get your hands on the bedside, ideally
with someone who knows how to do this
or even with sort of remote oversight.
So, you know, send your, send your clips to,
to a colleague post your clips on Twitter
for feedback, that kind of thing.
'cause it is really nice as you're learning this
to get some feedback for someone who has some, from someone
who has some experience.
- Right. And that sounds great. Okay. All right.
Any other questions?
Okay. And I'm nervous to say thank you again
because, but here we go.
Thank you so much Dr. Wis Carr.
This was an excellent presentation
and I, I know our audience learned a lot
and thank you everyone for joining us today.
Have a great rest of your day. Thanks Laura. Thank you. Bye.
Accurate assessment of volume status is a perpetual challenge in medicine. The detection of right-sided venous congestion can be particularly difficult with traditional clinical and POCUS techniques; but often has significant pathologic consequences. Watch Dr. Katie Wiskar to learn how to perform a VExUS exam – Venous Excess UltraSound – and see examples of how to incorporate this technique into your clinical practice.
What You'll Learn
Upon viewing this webinar, viewers will be able to provide better patient care by having a better understanding of how to:
- Perform the scans that comprise the VExUS exam
- Interpret the individual waveforms that comprise a VExUS exam
- Appreciate the caveats and pitfalls of a VExUS exam
- Showcase examples of how a VExUS exam can be integrated with other POCUS and clinical information to provide a comprehensive volume status assessment
Division of General Internal Medicine
University of British Columbia
Dr. Katie Wiskar is a General Internist at Vancouver General Hospital. She completed her core Internal Medicine and General Internal Medicine fellowship at the University of British Columbia. She completed a year of POCUS fellowship, including 6 months of Critical Care Ultrasound fellowship at Western University in London. Her POCUS passions include VExUS and POCUS evaluation of volume status; all things echocardiography; and clinical integration of ultrasound findings. Outside of medicine, you can find her on the beach volleyball court, hiking in the mountains, or playing with her two sons.
This educational webinar is intended for healthcare professionals and not for patients or consumers. The material is provided for general educational purposes, as a reference and a supplement to professional experience, education and training, and should not be considered the exclusive source for this type of information. This educational webinar is not intended to recommend any device for a particular indication or to provide indications for use for any device. At all times, it is the professional responsibility of the practitioner to exercise independent clinical judgment in each particular situation. Fujifilm assumes no responsibility or liability for any misuse of the information imparted in this webinar. This educational webinar does not supplement, replace, or supersede device labeling, including instructions for use, which accompanies any FUJIFILM Sonosite product.