Updated: July 2021
A peripheral vascular assessment at Inform Podiatry will determine if you have enough blood flow to your feet. You need enough blood flow to keep your feet healthy and repair any injury that may occur to your feet such as if you stand on something sharp and cut the skin.
The key sections to Inform Podiatry's evidence based assessment are:
Assessing lifestyle factors affecting your circulation
Assessment of pain or discomfort in your legs when you walk
Checking the foot pulses
Checking the rhythm of your heart beat
Using a Doppler ultrasound to assess pulse waveforms (top picture)
Using a special Doppler light probe and a toe cuff to assess systolic toe pressures (bottom picture)
We know that a number of factors affect your circulation by causing fatty deposits called plaque to build up inside the artery which make it harder for the blood to flow from your heart to your feet. These factors include smoking, high cholesterol, high blood pressure, high blood sugars, being overweight or being inactive.
Pain or discomfort in your legs when you walk
When you walk faster or uphill, your leg muscles need more oxygen from the blood. If the blood flow is restricted by changes to the arteries then the muscles begin to run out of oxygen and cause pain which stops you walking. Once the blood flow catches up, the pain stops and you begin walking again. This type of leg pain is called intermittent claudication and may be a symptom of peripheral artery disease.
There are two main foot pulses we check, one is on the top of the foot and the other behind the back of the ankle. Sometimes we check additional lower leg or foot pulses. If both foot pulses can be felt in either foot and you do not have intermittent claudication then no further assessment is required.
Rhythm of your heart beat
The rhythm of your heart beat can be assessed by either feeling the pulse rhythm during palpation or by looking at the pulse waveform rhythm with a Doppler. Your heart rhythm can be regular or irregular (called an arrhythmia). We refer all patients with an undiagnosed arrhythmia to their general practitioner (GP) for further assessment. Some arrhythmias such as atrial fibrillation (a fast and irregular heart beat) increase your risk of a stroke so diagnosing the type of arrhythmia and medical management is important.
Doppler ultrasound to assess pulse waveform
We use a handheld Doppler ultrasound which creates a soundwave of the blood flow through your foot artery. When the heart contracts (beats) blood flows toward the feet and the foot artery expands. The heart contraction finishes and the blood briefly flows back toward the heart. As the artery contracts to it's original size the blood flows toward the feet again. This change in blood flow direction produces a triphasic soundwave (three waves). As you age the artery becomes less flexible and the soundwave may become biphasic (two waves). With peripheral artery disease the blood flow through the artery is further reduced to a monophasic wave (single wave) and with severe peripheral artery disease not enough blood flow for any Doppler soundwave. If both foot pulses are triphasic or biphasic in both feet and you do not have intermittent claudication then no further assessment is required. We refer all patients with monophasic or absent Doppler soundwaves to their GP for further assessment and management.
Toe systolic pressure test
To measure the blood flow in a toe (usually your big toe) we use a special Doppler light probe called a PPG (photoplethysmography). We also use a mini blood pressure cuff is placed around the base of your toe and the probe is attached to the end of your toe. We inflate the cuff the same as when your GP checks your blood pressure. When the blood flow in the toe stops we deflate the cuff until the blood flow returns. This is the systolic pressure for the toe. We refer all patients with very low toe systolic pressures to their GP for further assessment, management and referral to a vascular specialist (if required).
With your consent, we send a vascular assessment report to your GP and other relevant specialists such as a Cardiologist.
Barry Matthews has over 30 years experience in vascular assessment and was a clinical instructor at QUT from 2010 to 2020 in vascular assessment for the Podiatry students.
Australian absolute cardiovascular disease risk calculator https://www.cvdcheck.org.au/
Online cardiovascular disease Guidelines https://auscvdrisk.com.au/risk-calculator/#login
Kieback, Arne G., Roman Gähwiler, and Christoph Thalhammer. "PAD screening: why? whom? when? how?–a systematic review." Vasa (2020).
Hinchliffe, Robert J., et al. "Guidelines on diagnosis, prognosis, and management of peripheral artery disease in patients with foot ulcers and diabetes (IWGDF 2019 update)." Diabetes/metabolism research and reviews 36 (2020): e3276.
Tehan, Peta Ellen, et al. "How sensitive and specific is continuous-wave Doppler for detecting peripheral arterial disease in people with and without diabetes? A cross-sectional study." Diabetes and Vascular Disease Research 15.5 (2018): 396-401.
Tehan, Peta Ellen, et al. "Diagnostic accuracy of resting systolic toe pressure for diagnosis of peripheral arterial disease in people with and without diabetes: a cross-sectional retrospective case-control study." Journal of foot and ankle research 10.1 (2017): 1-7.
Conte, Michael S., et al. "Global vascular guidelines on the management of chronic limb-threatening ischemia." European Journal of Vascular and Endovascular Surgery 58.1 (2019): S1-S109.
Inform Podiatry provides these webpages for general advice. Please book an appointment at Inform Podiatry for individual assessment and treatment of your foot or lower leg condition.
Cardiovascular disease | Peripheral artery disease | Blood flow assessment | Circulation assessment | Vascular assessment | Leg pain when walking | Intermittent claudication | Ischaemia| Ischemia | Arrhythmia | Atrial fibrillation