Chronic Limb Ischaemia

Question 1

What is chronic limb ischaemia?

Answer 1

A peripheral arterial disease resulting in the symptomatic reduction of blood supply to a limb.

Question 2

What typically causes chronic limb ischaemia?

Answer 2

Atherosclerosis (or rarely vasculitis)

Question 3

What are the risk factors for limb ischaemia?

Answer 3

Same as RFs for atherosclerosis:

• Smoking
• Diabetes mellitus
• Hypertension
• Hyperlipidaemia
• Increasing age
• Family history
• Obesity and physical inactivity

Question 4

How are the symptoms of chronic limb ischaemia classified?

Answer 4

Fontaine’s Classification

Question 5

Outline Fontaine’s Classification.

Answer 5

Stage 1- Asymptomatic
Stage 2- Intermittent Claudication
Stage 3- Ischaemic Rest Pain
Stage 4- Ulceration, Gangrene or Both

Question 6

What is intermittent claudication?

Answer 6

• Cramping pain in the calf, thigh, or buttock
• After walking a fixed distance (the ‘claudication distance’)
• Relieved by rest within minutes.

Question 7

What is Buerger’s Test?

Answer 7

• 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

Question 8

What is Leriche Syndrome?

Answer 8

• Peripheral arterial disease of the aortic bifurcation

- Presents as buttock/thigh pain and erectile dysfunction

Question 9

What is critical limb ischaemia?

Answer 9

Advanced form of chronic limb ischaemia

Question 10

How is critical limb ischaemia defined?

Answer 10

• ABPI less than 0.5
• Presence of ischaemic lesions of gangrene
• Ischaemic pain on rest for 2+ weeks requiring opiate analgesia

Question 11

What is an ABPI?

Answer 11

A measure of BP in the upper and lower limb, allowing them to be compared

Question 12

How is ABPI calculated?

Answer 12

Ankle BP/Brachial BP

Question 13

How would an ischaemic limb typically look/feel?

Answer 13

• Cold
• Pale
• Weak/absent pulses

Question 14

How is ABPI used to classify ischaemia severity?

Answer 14

Normal 0.9+
Mild<0.9
Moderate<0.8
Severe<0.5

Question 15

What could an ABPI of 1.2+ mean

Answer 15

Interpret with caution, artery calcification can also cause a falsely high ABPI

Question 16

What imaging should be used for critical limb ischaemia?

Answer 16

• Doppler USS

- CT angiography

Question 17

How should a CVS risk assessment be done?

Answer 17

• ECG
• Bloods (lipid profile)
• Cap glucose
• BP

Question 18

How is critical limb ischaemia surgically managed?

Answer 18

• Angioplasty (+- stenting) or Bypass

- Amputation (if gangrenous/septic, or if patient isn’t suitable for angio/bypass)

Question 19

When is surgery offered?

Answer 19

When risk factor reduction and supervised exercise aren’t reducing symptoms

Question 20

What medical management is used in critical lib ischaemia?

Answer 20

• Lifestyle advice (smoking cessation, regular exercise, weight reduction, supervised exercise)
• Statin therapy (ideally atorvastatin 80mg OD)
• Anti-platelet therapy (ideally clopidogrel 75mg OD)
• Optimise diabetes control

Question 21

What complications may occur in chronic limb ischaemia?

Answer 21

• Sepsis/infection
• Ulceration
• Reduced mobility and QoL
• Acute-on-chronic Limb ischaemia

Question 22

What is the mortality rate in critical limb ischaemia?

Answer 22

50% at 5 years