Chronic Limb Ischaemia Flashcards
What is chronic limb ischaemia?
A peripheral arterial disease resulting in the symptomatic reduction of blood supply to a limb.
What typically causes chronic limb ischaemia?
Atherosclerosis (or rarely vasculitis)
What are the risk factors for limb ischaemia?
Same as RFs for atherosclerosis:
- Smoking
- Diabetes mellitus
- Hypertension
- Hyperlipidaemia
- Increasing age
- Family history
- Obesity and physical inactivity
How are the symptoms of chronic limb ischaemia classified?
Fontaine’s Classification
Outline Fontaine’s Classification.
Stage 1- Asymptomatic
Stage 2- Intermittent Claudication
Stage 3- Ischaemic Rest Pain
Stage 4- Ulceration, Gangrene or Both
What is intermittent claudication?
- Cramping pain in the calf, thigh, or buttock
- After walking a fixed distance (the ‘claudication distance’)
- Relieved by rest within minutes.
What is Buerger’s Test?
- Test for severe ischaemia
- Lye the patient supine and raising their legs until they go pale and then lower them until the colour returns (or even until hyperaemic)
- The angle at which a limb goes pale is Buerger’s angle
- An angle of less than 20 deg. is severe ischaemia
What is Leriche Syndrome?
- Peripheral arterial disease of the aortic bifurcation
- Presents as buttock/thigh pain and erectile dysfunction
What is critical limb ischaemia?
Advanced form of chronic limb ischaemia
How is critical limb ischaemia defined?
- ABPI less than 0.5
- Presence of ischaemic lesions of gangrene
- Ischaemic pain on rest for 2+ weeks requiring opiate analgesia
What is an ABPI?
A measure of BP in the upper and lower limb, allowing them to be compared
How is ABPI calculated?
Ankle BP/Brachial BP
How would an ischaemic limb typically look/feel?
- Cold
- Pale
- Weak/absent pulses
How is ABPI used to classify ischaemia severity?
Normal 0.9+
Mild<0.9
Moderate<0.8
Severe<0.5
What could an ABPI of 1.2+ mean
Interpret with caution, artery calcification can also cause a falsely high ABPI
