Upper & Lower Extremity Physiologic Exams

CVT Vascular 1

What is an ABI comprised of?

CW waveforms

pressure analysis

What should be the results of an ABI on a healthy patient?

pressure consistent in arms & legs

triphasic CW waveforms

What do the different types of physiologic exams provide?

ABI : initial assessment to establish arterial flow

segmental : determine level/segment of disease

PVR : same as seg but only will waveforms (NO pressures)

What are some capabilities of physiologic testing?

determines % of blood flow perfusing an extremity

determines presence & severity of occlusions

often 1st line of defense in establishing arterial disease

able to account for amount of perfusion by collateral flow (US CANT DO THIS)

What are some limitations of physiologic testing?

unable to distinguish between stenosis vs occlusion

multi-level disease makes it difficult to categorize & decipher specific segments

shows calcified vessels as falsely elevated

artificially elevated thigh pressures due to girth

dialysis patients with fistulas in UE

What should the CW probe be positioned in?

45 - 60 degree angle

What is the PPG sensor?

evaluates the blood flow in the the digits utilizing an infrared sensor that traces the RBCs & produces a distinct tracing

Where should you use a 10cm cuff?

ankles

calves

upper arm

forearm

When should you use a 12cm cuff?

high & low thigh

larger patients

If the cuff is too large how will the BP present?

artificially lower

If the cuff is too small how will the BP present?

artificially higher

What are some contraindications for an ABI or WBI?

patients with…

arterial bypasses

stent placement

deep venous thrombosis

recent groin access

open ulcerations

recent radial or brachial artery access

history of lymph node removal

mastectomy

How do you calculate an ABI?

higher RT/LT ankle pressure / higher arm pressure

How do you calculate an WBI?

higher RT/LT wrist pressure / higher arm pressure

What would indicate aorta-iliac segmental disease?

bilateral thigh pressures less than brachial pressures OR

bilateral high thigh indices of less than 1.25 (difference)

What would indicate ilio-femoral segmental disease?

unilateral thigh pressures less than brachial pressures OR

unilateral high thigh indices of less than 1.25 (difference)

What would indicate femoral-popliteal segmental disease?

pressure drop of 20 - 30 mmHg + from the high thigh OR

pressure drop of 20 - 30 mmHg + from the low thigh to the calf

What would indicate tibial peroneal segmental disease?

pressure drop of 20 - 30 mmHg + from the calf to any of the ankle pressures

A patient experiencing no symptoms may present with an ABI/WBI of..?

> or = 1.0

A patient experiencing claudication may present with an ABI/WBI of..?

< 0.80

A patient experiencing resting pain may present with an ABI/WBI of..?

< 0.40

A patient experiencing impending gangrene may present with an ABI/WBI of..?

< 0.20

A patient experiencing no symptoms may present with a TBI of..?

> 0.70

How would we categorize a mild disease with an ABI? What about TBI?

ABI : 0.90 - < 1.0

TBI : 0.60 - 0.69

How would we categorize a moderate disease with an ABI? What about TBI?

ABI : 0.50 - 0.90

TBI : 0.59 - 0.40

How would we categorize a severe disease with an ABI? What about TBI?

ABI : 0.30 - 0.50

TBI : < 0.39

How would we categorize a critical disease with an ABI?

ABI : < 0.30

What would be considered a brachial pressure gradient?

brachial pressure from one arm to the other has a > or = 15 - 20 mmHg difference

A significant change in a patient’s ankle/wrist brachial index form one visit to another is defined as?

> or = 0.15

What is reactive hyperemia?

a method to stress the flow in the arteries of the lower extremity when a patient is unable to ambulate however it is considered out-dated

What do you need to get a positive result for a physiologic stress test?

post pressure drop of 15-20% + at the 3-minute mark

How do you calculate a physiologic stress test?

take the pressure at the 3 minute mark & divide it by the resting pressure then take that number subtracting it by 1, then multiplying it by 100

ex:

resting pressure is 128 mmHg

3 minute post exercise pressure is 63 mmHg

63 / 128 = 0.49

1 - 0.49 = 0.51

0.51 × 100 = 51% drop

What is an indication for a physiologic stress test?

claudication

What is a contraindication for a physiologic stress test?

cardiac problems

recent stroke

impaired ambulation

severe hypertension

SOB

What should the post-treadmill recovery time be for a patient with no disease?

< 3 minutes

What should the post-treadmill recovery time be for a patient with single-level disease?

2 - 6 minutes

What should the post-treadmill recovery time be for a patient with multi-level disease?

6 - 12 minutes

What should the post-treadmill recovery time be for a patient with severe occlusive disease?

> 15 minutes

How do you examine for popliteal entrapment?

perform ABI first

examine flexion maneuvers plantar & dorsi flexion by either :

interrogating with a PPG sensor on pad of great digit or

obtaining CW doppler waveform at both the PTA & DPA

What is plantar flexion?

the pointing of your toe to extend your entire foot

What is dorsi flexion?

the backwards being of your foot

What does laser doppler do?

assesses the characteristics of the microvascular blood volume in the capillary beds of the skin

What are some capabilities of laser doppler?

can determine the healing potential of a wound / ulcer & at which level to amputate

What are some limitations of laser doppler?

ulcerations (skin must be intact)

if patient is unable of remaining still

What are the prominent branches off the subclavian artery?

vertebral

thyrocervical

internal thoracic

costocervical

What is allen’s test?

determines dependency of the radial / ulnar arteries by evaluating waveforms whilst giving manual pressure to each artery individually

What is thoracic outlet syndrome?

compression of subclavian vein/artery by 1st rib resulting in either stenosis, occlusion, embolization, or swelling

What are the 3 types of thoracic outlet syndrome? Which is most common?

neurogenic : caused by compression of brachial plexus by rib (most common)

venous : arm abduction causes subclavian vein to be compressed

arterial : arm abduction & rotated causes subclavian vein to be compressed

How do you examine for thoracic outlet syndrome?

perform WBI 1st

PPG sensors are placed on digits to evaluate waveforms during different maneuvers such as :

sitting still & turning head

moving hands slightly backwards on lap (costoclavicular)

abducting arm 90 & 180 degrees

& whatever position the patient feels symptomatic in

What is the differences between primary & secondary raynaud’s?

primary : idiopathic, symptomatic for years, color changing of digits, bilateral, no ulcerations

secondary : caused by underlying condition, rapid onset, unilateral, occlusion, ulceration present

How do you examine for raynaud’s?

perform WBI 1st

use PPG tracings & evaluate perfusion at rest, in cold water, & in warm water for approximately 1 - 3 minutes each