Chronic Limb Ischaemia

Question 1

Definition?

Answer 1

Peripheral arterial disease resulting in sympathetic reduced arterial blood supply to the limbs

Question 2

RF?

Answer 2

• Smoking
• DM
• Hypertension
• Hyperlipidaemia
• Age
• FH
• Obesity and physical inactivity

Question 3

ddx?

Answer 3

• Spinal stenosis-pain radiating down back and lateral leg and symptoms relieved when sitting
Acute limb ischaemia-less than 14 day duration and present in hours

Question 4

Aetiology?

Answer 4

CVD risk factors

Question 5

CP?

Answer 5

• Depend on severity
• Intermittent claudication-cramping pain in leg after walking fixed distance, relieved by rest
Buerger’s angle; an angle ofless than 20 degreesindicates severe ischaemia.

Question 6

Stages?

Answer 6

• Stage I-asymptomatic
• Stage II-intermittent claudication
• Stage III-ischaemic rest pain
Stage IV-ulceration, gangrene or both

Question 7

Critical CP?

Answer 7

• Ischaemic rest pain for greater than 2 weeks duration, requiring opiate analgesia
• Presence of ischaemic lesionsorgangreneobjectively attributable to the arterial occlusive disease (Fig. 1)
• ABPI less than 0.5
• On examination, the limbs may bepale and cold, withweak or absent pulses. Other signs include limb hair loss, skin changes(atrophic skin, ulceration, or gangrene), and thickened nails.

Question 8

Pathophysiology?

Answer 8

• Hyperlipidaemia, free radicals , hypertension infections or inflammation cause endothelial cell dysfunction and arterial wall stress.
• Process of sub-endothelial inflammation or atherosclerosis causes thrombosis or TE.
• The phenotype of smooth muscle cells also changes causing a hardening of the arterial wall.
• The wall becomes so thick and hypoxic, HIF-1a is released promoting angiogenesis and arteriogenesis
• But this compensation can be overwhelmed and widespread ischaemia and hypoxia due to obstruction can occur.

Question 9

Investigations first line?

Answer 9

• PV exam, CVD risk assessment, thrombophilia and homocysteine levels (low means less risk of CVD event)
• ABPI confirms diagnosis and quantifies severity
Doppler ultrasound to assess location

Question 10

Investigations second line?

Answer 10

• CT/MRI angiography

Question 11

Management first line?

Answer 11

• Lifestyle advice and supervised exercise programme
• Statins
• Anti-platelet therapy
• Diabetes control

Question 12

Management second line?

Answer 12

• Surgical
• First line if critical
• Angioplasty
• Bypass grafting-diffuse or young
• Combination
• Amputations if incurable or sepsis

Question 13

Prognosis?

Answer 13

5 yr mortality rate is 50%

Question 14

Complications?

Answer 14

• Sepsis
• Acute-on-chronic ischaemia
• Amputation
• Reduced mobility and quality of life
• Critical limb ischaemia
• Depends on amputation, claudication and lifestyle