Term
| Purpose of Arterial Physologic Testing-LE |
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Definition
| 1.Evidence of arterial occlusive disease/PAD. 2.Is it responsible for symptoms. 3.Arterial disease vs. neurospinal. 4.If disease, how severe. 5.Assess increase/decrease in serial follow-up. |
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Term
| Types of Indirect Physiologic Tests |
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Definition
| Pressure assessment (ABI,Segmental), Plethysmography (PVR,PPG), Doppler Waveform analysis. Exercise Stress Test. |
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Term
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Definition
| Pain when walk? Both? Which is worse? Where in the leg: Calf(SFA/POP),Thigh(PFA),Buttock or Hip(Iliacs)? Pain progressive, stop you from walking? How many blocks can walk? Does pain leave w/rest? Bypass graft/arterial operation? Smoker? Diabetes Mellitus/Insulin? CVA/TIA/MI? |
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Term
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Definition
0=no pulse
1=weak pulse
2=normal pulse
3=very strong pulse or aneurysmal pulse
Can be taken in the groin(EIA/CFA), POP, Ankle(DPA/PTA). |
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Term
| Physical Signs of Disease |
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Definition
Pallor,Pain,Paresis,Pulselessness
Coldness
Dependant Rubor
Cyanotic Toes
Ulceration
Non-healing Wound |
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Term
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Definition
| Progressive pain with exercise in the calf,thigh,buttock or hip. relieved by rest. |
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Term
| Segmental Pressure Principle |
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Definition
In a normal individual in a supine position, ankle systolic pressure is ≥
brachial pressure. Should be in a warm room in basal state. |
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Term
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Definition
Bladder should be 20% wider than limb diameter.
Thigh=18cm
Arms/Calf/Ankle=10 or 12cm
Metatarsal(Child Sz)=9cm
Digit=2 or 2.5cm
12cm cuffs on Thigh in 4-cuff method. |
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Term
| Steps of Segmental Limb Pressures Test |
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Definition
1.Patient Prep.
2.Cuff Application.
3.Obtain bilateral arm systolic pressures & compare.
4. ABI
5.Segmental Pressures. |
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Term
| Doppler Pressure Sites for ABI/Segmentals |
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Definition
Dorsalis Pedis; Easy to compress,hard to find. Extension of Ant. Tibs.
Posterior Tibial; Harder to compress, easier to find. |
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Term
| Photo-Plethysmography (PPG) |
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Definition
| Digit pressure/waveform aquisition w/transmitted infrared light. Reflected light for cutaneous flow. Pros: bilateral capability, convenient,less skill. Cons: ambient light interference, no audible pulse, not good for severe disease. |
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Term
| Ankle/Brachial Index (ABI) |
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Definition
| Bilateral Ankle Pressures divided by the higher brachial pressure. Highest ankle pressure is used for reported ABI. |
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Term
| Segmental Pressure Cuff Inflation |
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Definition
| Inflate the cuff 20mmHg above systolic pressure (Doppler Sound disappears). High thigh cuff in 4-cuff method is inflated 40mmHg above arm pressure. |
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Term
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Definition
| 18cm wide cuff on thigh. Normal Thigh Pressure=Brachial Pressure. |
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Term
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Definition
2 12cm thigh cuffs. "Normal"(high-thigh cuff artifact) high-thigh
pressure is 20-30mmHg>Brachial Pressure. Can differentiate Aortoilliac vs SFA disease. |
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Term
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Definition
Normal > 0.75
Abnormal < 0.66
Good for small vessel disease & diabetic patients w/calcified, incompressible vessels. |
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Term
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Definition
> 1.0=Normal(usually)
> 0.90=Normal(sometimes abnormal)
<0.90=Abnormal
<0.8=Probable Claudication
<0.5=Multi-level disease or long occlussion.
<0.3=Ischemic Rest Pain. |
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Term
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Definition
| Brachial Systolic Pressure <100mmHg or > 200mmHg. Ankle pressure may be 25% lower than brachial and be normal. |
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Term
Segmental Limb Pressure Interpretation
Tips |
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Definition
1.Look @ ABI first.
2.Confirm ankle waveforms & pressures match. Normal=Normal/Abnormal=Abnormal.
3.Determine Disease location & thigh pressures.
4.Determine multilevel vs. single level disease.
4. Determine severity & if related to symptoms. |
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Term
| Segmental Limb Pressure Interpretation |
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Definition
| Compare to contralateral limb. Compare to adjacent segments. Compare to brachial pressure. ≥ 30mmHg pressure gradient is significant(>60%) stenosis, in the presence of an abnormal ABI. |
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Term
| High-Thigh Pressure Stats for A-I Disease |
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Definition
Normal thigh pressure ≥ 20mmHg above brachial pressure.
Negative Predictive Value: 100%
Positive Predictive Value: 42% |
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Term
| Pressure Limitation: Calcified Arteries |
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Definition
In: diabetics,chronic steroid therapy, renal dialysis patients.
Clues: ABI>1.30, unobtainable pressures,
high pressures distally compared to proximal pressures. |
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Term
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Definition
| Quantitative information on limb perfusion. Easy to do. Substantial clinical validation. |
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Term
| Pulse Volume Recording (PVR) |
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Definition
| Aka: Volume Pulse Recording. Air (pneumo) plethysmography. Limb volume changes w/systole, air is displaced in a cuff and change is recorded. Cuff inflated to 60 +-5.If gain is too low can make a normal waveform abnormal looking. |
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Term
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Definition
| Has a sharp upslope & a prominent reflected wave,dicrotic notch, in late systole/early diastole. |
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Term
| PVR Waveform with Mild Disease |
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Definition
| The waveform will broaden & reflected wave will disappear. Slight loss of amplitude. |
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Term
| PVR Waveform with Moderate Disease |
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Definition
| Waveform has a rounded peak,no reflected wave & a pronounced decrease in amplitude. |
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Term
| PVR Waveform with Severe Disease |
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Definition
| PVR is low amplitude, almost flatline. |
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Term
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Definition
Tremor-motion. Distal disease with proximal occulusion. Subjective.
Atrial Fib. distortation. |
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Term
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Definition
| Easy to learn. Assessment of global limb perfusion. Metatarsal & toe evaluation. Unaffected by calcified arteries. |
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Term
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Definition
| CFA,SFA,POP,PTA(at Medial Malleolus) & DPA(Dorsalis Pedis). |
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Term
| CW Doppler Waveform Analysis |
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Definition
| Warm room & basal state. 4 or 8 MHz Cw Doppler. 45-60 degree angle. Clean waveforms. Use: Analog,zero-crossing detector or FFT color spectrum analyzer. |
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Term
| CW Doppler Waveform Interpretation |
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Definition
| Subjective assessment. Look for: loss of triphasic waveform, dampening of amplitude, slow upstroke. |
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Term
| CW Doppler Waveform Limitations |
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Definition
1.Junk signals; obesity,scar tissue, occluded artery.
2.Venous Interference; averaged signal.
3.Requires alot of skill. |
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Term
| Exercise Stress Testing Purpose |
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Definition
1.Differentiate true vascular claudication from pseudo-cladication.
2.Differentiate borderline normal from abnormal. 3.In patients w/combined neuropathy & vascular disease, determine which is limiting walking. |
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Term
| When to do Exercise Stress Testing |
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Definition
Intermittent claudicators.
ABI 0.85-0.4. Resting study is normal but patient has claudication. DO NOT do if SX @ rest and resting study is normal. |
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Term
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Definition
| Treadmill; 1.5-2mph, 5-10% grade, 5 min. walk time, take post exercise ankle pressures ASAP. |
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Term
| Contraindications for Exercise Test |
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Definition
| Questionable cardiac status,resting ischemia (ABI<0.3),ischemic ulceration, trouble walking, SX @ rest and resting study is normal. Can use toe raises or PORH. |
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Term
| Claudication Criteria; Exercise Test |
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Definition
| Post exercise ankle pressure of 60mmHg or less confirms a vascular etiology. |
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Term
| Post Occlusive Reactive Hyperemia (PORH) |
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Definition
Occlude distal thigh @ 20mmHg above limb pressure for 3 min. Very painful.
Cannot determine vascular vs pseudo-cladication. |
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Term
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Definition
| Substitue for PORH. 1 min then post exercise pressures. Cannot determine vascular vs pseudo-cladication. |
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Term
| Physologic Testing Limitations |
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Definition
Detects only hemodynamically significant disease(>60% stenosis).
Usually cannot determine stenosis from occlusion. Region but not site of disease. |
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