I spent the entire day taking tons of notes so that those of you who were not able to join us could keep up to date with all that went on. Other then a few lecture sessions here and there, we were able to attend all portions of the day. I have labeled each section under the corresponding session listed in the final program. Feel free to find which one interests you and read up!
CONCURRENT TUTORIALS
Tutorial #1: Options for Examining The Technically Challenging Patient
Steve Knight gave a presentation on solutions for examining patients with difficult scenarios. As a student, any patient outside of a normal body habitus proves as a challenge to me each and every day. Steve lectured on the types of challenging patients and options of how to work around them to get the best scan you can. Steve discussed patients with large body habitus, unna boots, in-patients who are hooked up to a thousand machines, uncooperative patients (Agitated, tremor at rest, arrhythmias, cannot hold breath, etc), and patients with non-compressible vessels.
Solutions:
- Don’t panic, what is the question being asked?
What are you capable of to do the best you can for THAT patient?
- Large patient: Fast for 6 months (haha), low
frequency transducer, turn patient on side, get help when needed to prevent from injuring yourself!
- Did you know the femoral vein has no fat pad!? So no reason to get a bad picture here!
- Uncooperative: Seek to understand why they are
upset.
o
Post surgical pain: talk patient through,
empathy, work with nursing staff, careful removing dressing
- Unna Boots: Avoid arterial studies (boot adds 20 to
30mmHg of pressure), remove completely if study must be done
- Arrhythmia: Regularly irregular (be consistent,
measure on same peak pattern) or irregularly irregular (be patient, reduce
pressure slowly)
- Non comp vessels:
o
The Pole test – find signal, slowly elevate
limb, measure height that signal is lost, multiple height x .78mmHg.
- Cannot hold breath: wait for it, watch breathing
cycle for perfect moment, have Doppler cursor positioned correctly for location
at end of respiration, and document multiple similar measurements to make the case.
Remember, bad information is worst than no information! It is better to say you could not get the results needed then to fake results just to show a picure.
Ann Kupinski, Kristen, and Steve Knight after the Early Morning Tutorial
SVU GENERAL SESSION
So how about that blackout? Mindy and I were NOT scared AT ALL........promise....kind of....
- There are 23,000 RVTs today!
- The Care Bill:
o Individuals qualified to perform the technical component of medical imaging exams will possess current certification. Establish minimum standards for personnel. The bill rids the field of people who are not certified to perform the exams properly.
o It's a good thing!
- Patricia Poe left us with some really good quotes to think about:
“The purpose of life is a life of purpose"
"Do something everyday that scares you"
"Well behaved women seldom make history"
"What would you do if you knew you could not fail”
"Focus our resources and energy on what is important, the
correct exam for every patient done well"
“People often ask me what is the most effective technique
for transforming their lives. It is a little embarrassing...after years and years of research, my best answer is just be a little kinder"
Congrats to the 2012 Professional Achievement and Service Award Winners!
Donna Blackburn, Michel Comeaux, Barton Bean, Jeanette Flannery, and Judy Friend
ARTERIAL PHYSIOLOGICAL TESTING
Translating Audible Doppler: Auditory to Visual Information
- Phasicity should only apply to audible
waveforms, direction should apply to spectral
o
Very Questionable
o
What it means is more important than counting phases
- Experienced sonographers can usually predict
what spectral waveform will look like from listening to Doppler
Would you be comfortable performing an exam without the audio Doppler?
Should Doppler be included in the system for
physicians?
Pressure Measurements: What's Right, What's Wrong?
- “Right Pressures”: No wall calcification, patient is at rest
and comfortable, horizontal, correct sized cuffs, must measure both arm
pressures.
- Too High: arterial wall calcification, hydrostatic pressure, cuff too narrow, patient anxious, arrhythmia
- Too Low: Cuff too wide, Subclavian stenosis/occlusion, hydrostatic pressure, extrinsic compression
- Wall calification: Flow will not be stopped even at 300 mmHg
- Hydrostatic pressure :
o 10 inches below level of heart decreases pressure by 20 mmHg
o 5 Inches above the heart level will reduce pressure by 10 mmHg
- If the ABI is lower than expected, then re-measure the higher brachial pressure. If pt is apprehensive at first the BP may be elevated initially and now decreased.
- Fibrous band can constitute a positional stenosis due to compression.
- If you hear an immediate pulse but not a succeeding beat, then that is the high systolic catching up in an arrhythmia. Continue decreasing pressure until continual beats are heard.
- Too High: arterial wall calcification, hydrostatic pressure, cuff too narrow, patient anxious, arrhythmia
- Too Low: Cuff too wide, Subclavian stenosis/occlusion, hydrostatic pressure, extrinsic compression
- Wall calification: Flow will not be stopped even at 300 mmHg
- Hydrostatic pressure :
o 10 inches below level of heart decreases pressure by 20 mmHg
o 5 Inches above the heart level will reduce pressure by 10 mmHg
- If the ABI is lower than expected, then re-measure the higher brachial pressure. If pt is apprehensive at first the BP may be elevated initially and now decreased.
- Fibrous band can constitute a positional stenosis due to compression.
- If you hear an immediate pulse but not a succeeding beat, then that is the high systolic catching up in an arrhythmia. Continue decreasing pressure until continual beats are heard.
Exercise Testing - When To Do It
- Three Formats - Motorized treadmill:
- Constant load
- Progressive Load – Increase 2% load every minute
- Maximum walking time
-
Post-exercise measurement: Absolute pressure,
ABI
- Historic standard -Constant load, 2mph, 12% grade, 4 min max time, absolute ankle pressures
- Consistency is most important!
- Indications:
- Historic standard -Constant load, 2mph, 12% grade, 4 min max time, absolute ankle pressures
- Consistency is most important!
- Indications:
o
All patients with known PAD?
§
Impractical (Time consuming)
§
Unsafe, risk of MI
§
Not cost-effective
o
All Patients with Suspected PAD?
§
Impractical
§
Abnormal resting ABI already demonstrates dz
(40%)
§
Not Cost-effective
o
Is there a question of presence of arterial
obstructive disease?
§
C/o leg pain with ambulation
§
Normal ABI
o
Functional impairment
§
Anatomic severity of disease
§
Self-reporting of distance/time is not reliable
§
Relative contrivutions of obstructive disease
and neuropathy to symptoms
o
Prognosis in pt with claudication
§
Decreased post exercise data = likelihood for
mortality of CV events
§
Inverse correlation
o
Surveillance
§
Evaluate success of intervention
§
Baseline early post-op
§
Indicator of recurrent disease
o
Research tool
-
Limitations
o
Unsteady patient
o
Cardiac risk
o
Right-Left Asymmetry
o
Need for intervention is known already, so there is no
benefit
o
Calcification – unreliable
-
Other testing options: Toe rises, timed walking,
reactive hyperemia, Independent leg exercise
The Arterial Speakers answering some Q&A. They handled all of the questions very well!
D.E. STRANDNESS, SCIENTIFIC SESSION
Longitudinal Changes in Size and Composition of Carotid Artery Plauqes Using Ultrasound
- Method of tracing plauqe longitudinally can be used to consistently assess changes in plaque size and composition.
Lower Extermity Fibromuscular Dysplasia Manifests Primarily in the External Iliac Artery
- Lower Extremity FMD has 5%
incidence rate
- Peripheral FMD signs (Two of which must be present): Turbulent flow, significant velocity shifts with no associated plaque, presence of beading on color Doppler
- Presenting symptoms: Most are asymptomatic, 3% have intermittent claudication
- Lower vessels effected: EIA and CFA, Not found below the femoral artery.
- Treatment: Medical management
- Criteria for percentage stenosis have not been validated yet
- Other disorders can demonstrate same appearance of turbulent flow and velocity shift: atheroscleorosis, systemic vasculitis, standing waves, arterial tortuosity
- Prevalence of lower extremity involvement in patients with other FMD present is unknown
- Patients tends to have a femoral bruit
- Peripheral FMD signs (Two of which must be present): Turbulent flow, significant velocity shifts with no associated plaque, presence of beading on color Doppler
- Presenting symptoms: Most are asymptomatic, 3% have intermittent claudication
- Lower vessels effected: EIA and CFA, Not found below the femoral artery.
- Treatment: Medical management
- Criteria for percentage stenosis have not been validated yet
- Other disorders can demonstrate same appearance of turbulent flow and velocity shift: atheroscleorosis, systemic vasculitis, standing waves, arterial tortuosity
- Prevalence of lower extremity involvement in patients with other FMD present is unknown
- Patients tends to have a femoral bruit
The GWU Vascular students enjoying a break between sessions
LUNCH WITH THE EXPERTS
"Duplex Guided Interventions"
Kelly Byrnes and Josh Cruz presented on the various different interventional procedures that can be performed with ultrasound guidance. The presentation started off with information regarding our growing role in the procedure room with assisting interventionalists. It was awesome to hear some positive news about growth available in our field. Personally working by the side of vascular surgeons at my clinical sites, I found this lecture to be very interesting! Anyone who is lucky enough to take part in OR procedures with vascular would thoroughly enjoy the information presented.
-
Advantages of Ultrasound Guidance: No Nephrotoxic use of contrast, no
radiation, less expensive, and portable
-
Disadvantages of Ultrasound Guidance: Not suitable for certain anatomy,
body habitus, calcified arteries, and lack of training
- Team: Experience sonographer and
interventionalist
-
Evolution from Diagnostic Medical Sonographer to
Interventional Sonographer
o
Potential for specialization
o
Advanced skill set
- Competition: The Interventionalist themselves
- Office Based Procedures: High Efficiency, control of
resources, higher reimbursement, patient satisfaction
- Getting Started
o
Find an interventionalist
§ One who respects rule of the sonographer
§
Mutual trust
o
First few cases perform in a suite where floro
can be used as backup
o
Types of Intervention
§
Thrombin Injection for Pseudo
·
Pre-Scan, Followup, intervention for failed
procedures
·
Check for thrombin allergies
· Check pulses on ipsilateral limb
§
Peripheral Arterial
· Angioplasty
· Stenting
· Popliteal Aneurysms
· Coil embolization
· Advantages: Exact location of stenotic region,
visualization of guidewire into the lumen, selection of proper balloon size for
artery, visualization of stent after placement
· Tip of guidewire must be seen at all time, heavy
calcification may interfere, use an experienced RVT
§
Endovenous ablations
·
Treat insufficiency
·
EVLT, RFA
·
Replaces ligation and stripping
·
Can be done in office
· Local anesthesia
·
Reduced post-op pain
· Pre-Op mapping: drawing available before
prepping
· Identify access poin
o Cannot guide wire through a varicose vein
o Cannot guide wire through a varicose vein
· Wire must be at least 2cm from the SFJ
·
Tumesence Anesthia
o
Serves as a buffer
o
Protects surroundings tissue, skin, and nerves
o
Vein must be 1 to 2 cm deep
o
May make it difficult to identify catheter
· Apply pressure with RFA, not laser
· RFA wire is more echogenic than laser
· Laser appears closed after, RFA may still appear
patent and have little blood flow
· Perforator
o
More demanding
o
Best done in long access
o
Mark the skin
o
Don’t move once identified!
·
Balloon Angioplasty for Dialysis Access
o
Identifying positive waste identifies the area
of problem
o
Same thing can be done on ultrasound as angio
US Guided procedures helps us advance our
specialty!
CEREBROVASCULAR HOT TOPICS
Transcranial Doppler: Techniques and Whose Role Is It?
- Transorbital can verify that there is no problem
downstream in the carotid artery
- Limitations
o
Operator Dependent
o
Machine dependent
o
Patient Dependent
o
Bone Window
-
Transtemporal Window – 5 Axial Planes
-
Billing is more expensive than carotid, but show same results and more
-
Embolus should not be on baseline, it should be
in the waveform
Volume Imaging: Carotid Plaque Assessment
- 2D finds atherosclerosis, quantifies degree of
narrowing, measure thickness; 3D measures volume.
- 3D offers quantification in volume and
morphology
- Previous studies showed 43% had plaque presence.
Bioimage study with 3D found 78% with plaque presence
Post-Carotid Intervention Assessment Criteria
-
In-stent restenosis
o
154 cm/s PSV = <30% Stenosis
o
224 cm/s PSV = >50% Stenosis
o
325 cm/s PSV = >80% Stenosis
o
Current criteria overestimates in-stent
restenosis
o
Criteria can be used to selecting reintervention
status
CASE STUDIES SESSION
All I can say is WOW! This was definitely my favorite part of the day. When you get stuck in a rut of doing the same exam all day long, nothing makes work more interesting then a unique and interesting case. Either one that is exciting and new, or one that makes you think outside of the box.
Some of the great cases presented included: a hidden floating popliteal artery thrombus, iatrogenic stenosis of the profunda femoris from a superficial femoral artery stent, an aortocaval fistula, and a bullet that was shot into a person and instead of fully penetrating the vessel wall it becomes an embolus!
I would try to describe but you really had to be there in person to see the great video clips!
Well that just about wraps up the conference day! I hope everyone had an amazing time. For those of you who couldn't make it, I hope the information above helped fill you in.
And so the sun sets on another day of vascular knowledge. See ya'll in the morning!
- Kristen
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