Page 42 - Virtual Vascular Vol 3

How to measure the ankle-brachial pressure index (ABPI)?
The probe is applied to the location of the target vessels and Doppler flow can be
heard. Normal Doppler waveform, the morphology of pulsatile blood flow velocity
tracings on spectral Doppler ultrasound, is triphasic. Bi-phasic and monophasic flow is 1. Apply blood pressure cuff to the arm, and apply sphygmomanometer pressure

abnormal. above the normal systolic whilst keeping the handheld Doppler probe on the
brachial artery at the antecubital fossa

2. Release the cuff pressure gradually, the first Doppler signal signifies the systolic
blood pressure at the brachial pressure

3. Repeat the process in the leg, with the cuff on the mid-/ lower- calf, and the
probe on the posteriotibial or dorsalis pedis artery, these will be the ankle
pressure

4. The ratio is normally 0.9-1.0. Calcified arteries or subclavian stenosis may give a
falsely high ABPI.

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