Doppler Segmental Pressures (LE) Flashcards
What are limitations of a Doppler segmental pressures exam
- cannot discriminate between stenosis and occlusion, or the precise area of obstruction
- cannot discriminate between CFA and external iliac disease
- may give falsely elevated Doppler on calcified vessels (patients with diabetes and end stage renal disease are common with this)
- wrong cuff size can give false pressures
- difficult to interpret multi-level diseases
- patients with CHF may have decreased ankle/brachial indices
Patients with these conditions may not be able to get pressure scans
(6)
DVT, dialysis access, lymphedema, stent, bypass graft, patients who had mastectomy
How long should patients rest before having this exam done
20 minutes
Ideally the cuff bladder should be placed over the______
Artery
It is VERY important that the width of the cuff is around ____% greater than the diameter of the limb
20%
With the four cuff (Bilateral) the cuffs are placed on the brachial (upper arm) and what other four areas?
High thigh (with a longer cuff for thighs)
Low thigh/above the knee (AK)
Below the knee (BK)/calf
At the ankle
With the three cuff method, the cuffs are placed at the brachial(upper arm), and what other 3 locations
One thigh cuff (19 X 40cm)
Below the knee/calf
At ankle
What is the average cuff size (excluding the thigh cuffs)
12 X 40 cm
For optimal Doppler signal the probe should be at a __ to __ degree angle to skin, with the blood flow moving ___ to the probe.
45-60 degree angle ( at the knee it may be closer to 90 degrees bc of vessel angulation)
Blood flowing towards the probe (Antegrade)
What is a sphygmomanometer
A hand held automatic cuff inflator
What is the order for a sphygmomanometer pressure exam, starting with
1. brachial artery
- At ankle (for PTA and DPA, **if necessary peroneal A.)
- Calf/BK (for PTA or DPA, use the HIGHEST pressure for this level)
- Above the knee/AK (same as calf, may need popliteal A. If difficult to obtain)
- High thigh/HT (same as above the knee)
Why are we performing segmental pressures from ankle to thigh?
To eliminate the possible underestimation of the systolic pressure measurements
