Most Common Mistakes in the Vascular Lab - SD

Introduction

Hi, my name's Cindy Wand.
I'm from Columbia, Maryland,
and I will be lecturing on the most common
mistakes in the vascular lab.

There's a lot of common mistakes made in the vascular
laboratory, and I have the unique opportunity to see up
to about 500 different labs during the course of a year,
because I work for the accrediting body, the I-C-A-V-L.

And prior to telling you about
what these common mistakes are, I just wanted to point out
that the information that I've gathered on these mistakes is
from I-C-A-V-L accredited laboratory applications.

Currently there are
over 1500 accredited labs over at over 2300 sites.

These are all types
of laboratories at all types of locations.
They can be hospital-based laboratories
or private practices, imaging centers.

And there's a common thread that it's not,
the mistakes are not singled out to one type of laboratory.
Also, these labs can do anywhere between 100
to greater than 15,000 exams per year.
They come from multiple kinds of specialties such
as radiology, vascular surgery,
cardiology amongst others.

The exams are performed by credentialed
and non-credentialed technologists.

Poor Image or Doppler Waveform Quality

So one of the first biggest mistakes we see
is poor image or doppler wave form quality.
16% of the case studies
that we look at include poor doppler
wave form, and image quality.
And most of this has to do with lack
of equipment optimization.

Equipment isn't being adjusted
for the appropriate depth.
The PRF isn't being adjusted.
A lot of times people are using preset
packages in machines now, which give you a general baseline,
but they still need to be tweaked now
and then to get the most optimal study.

Here's just one example of a poor waveform.
I looked through an entire venous exam
and every waveform in the exam had this same appearance,
which really doesn't give us any diagnostic quality.

Here's another example of venous exam
where we don't actually even see the entire waveform.
So again, it's not
of any diagnostic quality to the interpreter.

This is an example of something where, though I know
what, and you may know what we're looking for,
it's difficult to see in this image
what exactly we are supposed to be seeing.
It would be if there was an arrow to label
where this varicose vein is, it could be towards the top
of the screen, although
there's something towards the bottom.
And so again, this is just one of those unclear images
that could have been optimized
or could have been labeled better.

Here's another example of an image that was not optimized.
This is the carotid bulb.
And I, as you can see there, there's very little of the bulb
that's visible in this image.

Here's an example of some waveform quality that's very poor.
This is a PR exam.
Obviously we don't know
what was going on with this patient.
It could have been that the patient was moving
or that there was other problems with the exam,
but if that's the case, then maybe this isn't the
appropriate exam to be doing on this patient.

Keep in mind too, that when we ask for case studies
and accreditation applications, we're asking
for people's best work.
So if you did a thousand PVR studies
and you chose this as one of three of your best cases
of the year, that's very questionable.

Poor Angle Correction

So the second most common mistake
that we look at is poor angle correction.
At least 12% of the cases
that we see demonstrate incorrect angle correction.
And this doesn't mean that there was just one angle in a
complete case study that was off.
This means that this is consistent
throughout the entire study.

Angles greater than 60 degrees are often used, which
I find very interesting considering.
That's probably the first thing I remember learning when I
started doing vascular ultrasound, was that we never,
ever used a degree over 60, angle over 60 degrees.

Often the cursor is not parallel to the vessel walls.
Doppler wave forms are even obtained in transverse
orientation, not only in venous studies,
but also we see them in some arterial studies as well,
which we all know is completely incorrect.

This is just kind of driving home that point
that if you use the wrong angle,
you obtain the wrong velocity
and it's the wrong interpretation.

So I have just a few examples again,
of poor angle correction or, or equipment optimization.
Here you can see that up here is the focal area.
The focal point is set up here,
but they're sampling way down here in the image,
and they used an angle of 63 degrees.
I'm not quite sure even what vessel this is.
It may be a subclavian,
but again, as we saw in the last images,
there's no labeling, so it's not quite clear.

Here's an example of a common iliac artery,
and I'll give them credit that yes,
common iliac arteries are difficult to image a lot of times.
But you can see that I,
I can't quite tell if this image is in longitudinal
or if it's a transverse image, but the Doppler waveform
or the Doppler cursor rather,
is pretty much dissecting that flow.

Hopefully in this case, if
this was a difficult case,
that it's reported in the final report
that the waveforms may be inaccurate due
to the poor visualization of the vessel
and the difficulty obtaining a good angle correction.
But in this particular case,
it was not included in the final report.

Here we have a, an ICA where you see here that the
cursor is not parallel to the vessel walls.
Here's the vessel walls here.
And so there need to be some manipulation
of the probe to get a better angle.

This is just one example
of many in this particular study where time was not taken
to adjust the doppler angle appropriately,
to get the most optimum velocities.

Incomplete Exams and Lack of Adherence to Written Protocols

So the third common mistake that we see is
incomplete exams
and lack of adherence to the written protocols.
About 18% of the cases are in completely documented.
They have limited gray scale images, sometimes very often,
no gray scale images,
Doppler waveforms are obtained from limited
areas in the vessels.
They're either just spot checked, they don't go
to the most distal ICA, for instance.
They don't walk the doppler through the vessel
as we've been taught many times.

There's no additional documentation of abnormal findings,
whether that be a mass that's adjacent to a vessel.
If there is a stenosis, it's often not documented pre,
mid and post stenosis.

And often the reasons that this may come about is
that people have incomplete or extensive
or outdated protocols,
and the staff is not following the same protocol.
And this is very important,
though it seems like a minor thing in laboratory,
it's actually quite important.

What you don't want to do is you don't wanna have a protocol
that's so extensive that it's difficult to follow,
that people are going to not use it.
And you wanna make sure that your protocols are reviewed
and updated regularly to be sure that your,
they reflect what you want performed
and documented in your laboratory
to give the physician the best information
for their interpretation.

Report Content Errors

The fourth most common mistake is going
to be report content errors.
15% of the final reports include content errors.
And this is very serious.

The final report can be used as a legal document,
and it's important to make sure that it's
as accurate as possible.
And of course, everyone
makes mistakes in the final reports,
but these errors tend to be quite blatant.
And again, these are on only a few exams
that these labs are sending into us.

So not only did someone not actually see these errors
and report them the first time they were proofread,
but yet they're being sent in to
have a peer review performed on them,
and once again, have not been, have not seen the errors.

Sometimes they're typographical errors.
Often we see transposition of the right
and left findings where in the body
of the report it will say the right side.
Yet in the conclusion, it will say that the
abnormalities on the left side,
often we'll see the images say right side
or identify a right-sided stenosis,
whereas in the final report, it will report it
as a left-sided stenosis.

A lot of times the information in the reports is incomplete,
that there's not an appropriate indication
for the exam, that the dates aren't included,
that the reports aren't signed, that the type of exam performed for the patient was not included.

As I just mentioned. Often there's
inappropriate indications.
We see a lot of indications that just say follow up or DVT.
Those are two very common ones,
and those aren't actually indications for the exam,
whereas leg swelling
or calf pain on walking is more
of an indication for the exam.

Here's just one example that I found where
of the transposition of the right
and left sides here, it says right in the body
of the report, referring to the right popliteal vein.
And then right below in the impression it says left.

Now I see all kinds of typographical errors and reports,
and though it is kind of funny when we look at them here,
it's rather, I would find it rather embarrassing
and me, if I put myself in the place of a patient,
if I took my report to take to my doctor
and I saw some of these things in the report,
I'd be a little bit worried about my care.

So these are very common things
that I've seen more than once.

We have a misspelling of carotid heterogeneous,
the regional vein when it should have been called the renal
vein endo rectum instead of endarterectomy
a complete partial obstruction,
which I'm still trying to figure out what that means.
And then hyper choice plaque, which probably was hyper coic,
but I'm not quite sure about that either.

So these are things that really should be caught
when these reports are proofread by the physician
before finalizing them.

Lack of Adherence to Diagnostic Criteria

So now we'll move on to the fifth most common mistake,
which is the lack of adherence to the diagnostic criteria.
25% of labs submit final reports that don't adhere
to their written diagnostic criteria.

What I mean by lack of adherence
to diagnostic criteria is they actually may inappropriately
apply percent stenosis, stenosis, that they don't
stay within the strata that they've chosen
as their diagnostic criteria.

Often physiologic testing uses a lot
of subjective terminology that has no real diagnostic
criteria attached to it.
And often we see that waveform analysis is not
reported correctly,
just revisiting subjective terminology.

There are no global definitions for things such as mild,
moderate, severe, or critical,
or what's moderately severe or what's mild to moderate.
So use of those terms can
create confusion if you aren't the person
that's actually interpreting it.

So if you're going to use subjective terminology,
it should be attached to a percent
or to the strata that's in your diagnostic criteria.

Often they will see that a vessel specific criteria is applied to all the vessels.
The most common in that is that people utilize the criteria
for the internal carotid artery stenosis
for all the vessels in the neck.
So they'll apply that to the common carotid
and the extra cranial, the subclavian.
And really the, those criteria have not been validated for those other vessels.

We even see those used.
The ICA criteria is often used even in the lower extremity
arteries, which certainly hasn't been validated for that.

So they should be aware of the vessel specific criteria,
and it should be only applied to those vessels
that it's been validated for.

A laboratory may decide to perform
or create their own diagnostic criteria.
But it's very important that if that's being done
or if you're taking a published criteria
and you're changing it, that you validate that by getting
additional information, by validating it, by comparing your
criteria and your non-invasive tests
to other imaging modalities such
as angiogram or CTA.

And what we do see is that there are a lot
of different specialties now that are kind
of dabbling in vascular testing.
And often these mistakes occur with diagnostic criteria
because the interpreting physicians haven't had
the appropriate training.

There's a little more to interpreting a vascular exam
than a lot of times a physician thinks.
And also because a physician interprets some types
of imaging modalities,
doesn't necessarily mean they've had the
appropriate training for others.

So it's very important to assure that the physicians
that are interpreting in your laboratory have been
appropriately trained.

So here's an example of a report that shows lack
of adherence to the diagnostic criteria.
So we see here that they have their criteria actually on the
report with the ranges and the velocities.

So we look down below,
and in the impression you see
that it says moderately severe,
right internal carotid artery re stenosis.

So as we just spoke about, I'm not sure
what moderately severe is.
So thinking that maybe we'll figure that out.
We'll go down below and we see that they say it's a 60
to 70% stenosis.
Well, there is no 60
to 70% stenosis up here in their strata.
There's 60 to 79 and 80 to 99.

So finally, we look
and we see that it's written as 2.6 meters per second.
Well, if we look up here at their chart,
2.6 meters per second would actually put it in the 80
to 99% category.

So this is a very outstanding example of
how this is not reflecting their diagnostic criteria,
and I'm not sure what the final diagnostics really
is on this patient.

Just some anecdotal information that I took
and pulled a hundred random applications from the I-C-A-V-L
just to see what diagnostic criteria was being used
for internal carotid artery stenosis.

And you'll see here there's quite a few.
There are certainly two
that are used more frequently than others,
but as you see, there's multitude of criteria just
for the internal carotid artery out there.
And it's, they're all usable, they've all been validated.
You just have to be sure that you choose the one
that works best for your laboratory
and that it is followed by all the interpreting
physicians in the laboratory.

Another thing that people often ask about diagnostic
criteria is they would like criteria to diagnose stenosis in other vessels.
Often, a lot of physicians want
to diagnose stenosis in the CCA
and I get questioned a lot about
where they could find a published criteria.

Previously, there really hadn't been a published criteria
for CCA stenosis,
however, just recently there was a
an article published in the Journal
of Vascular Surgery in January, 2010,
which does have a CCA stenosis criteria.

So that's just a bit of information
for you if your physicians want to interpret CCA stenosis.

Again, what's really important is to assure
that all the physicians that are interpreting
are using the same criteria
and they're applying it as the criteria is written.

How to Avoid These Common Mistakes

So how do we avoid these common mistakes?

Well, one good way is to do some quality assurance,
or we could do quality assurance
or maybe some quality assurance.

But the problem with this is
that the six most common mistake is
that laboratories don't perform any quality assurance.

We often see that laboratories have no comprehensive QA
plan, that a lot of times,
even if they have some type of quality assurance
that they're collecting inaccurate data,
they have poor methods of correlation.

It's difficult to really correlate exams to exams
that have been performed in other laboratories
because you don't know that you're using the same protocols
that you're using the same criteria.
You don't have the information necessary to correlate
to another lab.

Often the QA information isn't communicated
to the entire staff,
and then frequently there's some type of QA performed
and documented, but then nobody
does anything with that data.
And it kind of makes it, it's unnecessary then
that there's no reason to collect data
and find that you don't do anything with it.

So it'll help eliminate these common mistakes.
It's highly encouraged that you initiate
and maintain a quality assurance
and quality control program.

Peer review is very useful in seeing that
everyone in the laboratory that's performing exams
as performing them in the same manner,
following the same protocols that their techniques are
good and consistent.

It's also very good to assure
that physicians are using the diagnostic criteria
appropriately,
that the reports are being proofread and free of error.

It's also important for everyone in the laboratory
to get continuing education regarding both interpretation
and performance of examinations.

And one last thing that can help eliminate mistakes is
to really support accreditation
and credentialing of technologists to assure that the
quality of care in your laboratory is as high as it can be.