Class 11: LEA Physiological Testing Methods Flashcards

1
Q

what is the purpose of indirect physiological testing?

A

to detect arterial disease in LEA that is hemodynamically significant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what % stenosis is considered hemodynamically significant?

A

60%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

indirect physiological testing is often used as a screening process to ____

A

differentiate between true claudicators & pseudoclaudication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

indirect physiological testing is used to assess graft ____

A

patency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

5 limitations of indirect physiological testing

A
  1. can’t differentiate bw stenosis & occlusion
  2. only detects hemodynamically significant stenosis
  3. can’t precisely locate occlusive disease (no images!)
  4. hard to differentiate CIA & CFA stenosis
  5. may show falsely elevated pressures in diabetics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

another name for ankle brachial index

A

ankle arm index

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is ABI used for?

A

screening process to differentiate true claudicators from pseudoclaudicators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

ABI results are usually combined with ___

A

doppler waveform analysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

steps to take the ABI

A
  1. put patient in supine
  2. take BP of both arms; use the higher brachial BP
  3. take BP of both ankles (PTA or DPA)
  4. calculate both ABI ratios: LT ABI = LT ankle BP/highest brachial BP; RT ABI = RT ankle BP/highest brachial BP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what does an ABI ratio of 1.0-1.10 suggest

A

normal findings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what does an ABI ratio of 0.9-1 suggest?

A

minimal ischemia with minimal symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what does an ABI ratio of 0.5-0.9 suggest?

A

mild to moderate ischemia with mild to moderate claudication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what does an ABI ratio of 0.3-0.5 suggest?

A

moderate to severe ischemia with severe claudication or rest pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what does an ABI ratio of 0.3 or below suggest?

A

severe ischemia with rest pain or gangrene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what do doppler segmental surveys provide more information on?

A

location of disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

2 limitations of doppler segmental surveys

A
  1. can’t distinguish stenosis from occlusion
  2. still not location specific
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

2 techniques for doppler segmental surveys

A
  1. 3 cuff method
  2. 4 cuff method
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

which is preferred? 3 cuff or 4 cuff method?

A

3 cuff

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

why is 3 cuff method preferred over 4 cuff method with doppler segmental surveys?

A

the 4 cuff method can give falsely elevated pressures on the upper thigh

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how do you inflate the cuffs with doppler segmental surveys?

A

start from ankle & go up to the thigh

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what size should the blood pressure cuff be for doppler segmental surveys?

A

BP bladder should be 20% wider than the limb diameter

22
Q

a ___ mmHg pressure gradient is significant in the presence of an ____ ABI

A

20+ mmHg; abnormal

23
Q

if there is a pressure drop at the level of the high thigh, the disease level is at the ___

A

aortoiliac level

24
Q

if there is a pressure drop at the level of the low thigh, this indicates ___ disease

A

iliofemoral

25
if there is a pressure drop at the level of the high calf, this indicates ___ disease
femoropopliteal
26
if there is a pressure drop at the level of the low calf, this indicates ___ disease
tibioperoneal
27
how long does a patient need to rest prior to doing a segmental limb survey?
20 minutes
28
what patients' segmental pressures may be unobtainable or too high?
1. diabetics 2. chronic steroid therapy 3. renal dialysis patients
29
what ABI is considered too high for segmental limb surveys?
> 1.4
30
what causes some patients' segmental pressures to be too high?
calcified arteries
31
digit vessels are affected by calcific medial sclerosis. T/F?
false
32
what is a normal toe brachial index (TBI)?
> 0.75
33
what is an abnormal TBI?
< 0.66
34
what is exercise stress testing used for?
to induce reactive hyperemia in patients who may be well-collateralized
35
what is hyperemia?
increased blood flow to a part of the body
36
how to perform exercise stress testing?
1. perform ABI 2. put patient on treadmill for max 5 min 3. recalculate ABI
37
pressures should ___ after exercise stress testing
increase
38
what settings should the treadmill be at for exercise stress testing?
1.5-2 mph 10% grade 5 min
39
what are 2 substitutes for exercise stress testing when there are contraindications present for patients?
1. post-occlusive reactive hyperemia (PORH) 2. toe raises
40
what is post-occlusive reactive hyperemia?
when the distal thigh is occluded for 3 minutes with a blood pressure cuff
41
how long should toe raises be done before recording post-exercise pressures?
1 minute
42
what are two types of arterial plethysmography?
1. air (pneumo) plethysmography 2. photo-plethysmography
43
pulse volume recordings are a type of ___ plethysmography
air/pneumo plethysmography
44
for PVRs, limb volume changes with ____ & air is ____ within the cuff
systole; displaced
45
instantaneous ___ ___ is recorded with PVR
pressure change
46
PVR is unaffected by calcified arteries. T/F?
true
47
an advantage for PVR includes ___ evaluation
metatarsal & toe
48
an advantage for PVR includes assessment for global ___ ___
limb perfusion
49
a disadvantage of PVR includes atrial fibrillation. T/F?
true
50
how does photo-plethysmography work?
infrared light is transmitted into the tissue & reflected light is processed for cutaneous blood flow