Peripheral arterial disease

Question 1

What are the three types of peripheral arterial disease?

Answer 1

• Chronic limb ischaemia
• Critical limb ischaemia
• Acute limb ischaemia

Question 2

What is the natural history of peripheral arterial disease?

Answer 2

• Intermittent claudication
• Rest pain
• Non healing leg ulcer/gangrene
• Amputation

Question 3

Risk factors for vascular disease

Answer 3

Risk factors same as those atherosclerosis

• Smoking (if smoking is stopped will improve within a few weeks due to decrease in CO so more O2)
• DM
• Dislipidaemia
• Hypertension
• Physical inactivity

Question 4

Chief features of chronic limb ischaemia

Answer 4

• Intermittent claudication
  
  • ​Pain releived at rest, brought on by walking a distance

Question 5

What is beurger’s angle?

Answer 5

Elevation of leg from bed by 15-30 degrees for 30-60s causes pallor (sign of arterial insufficiency)

Question 6

What is ankle brachial pressure index?

Answer 6

Systolic ankle/systolic arm

Question 7

Typical ABPI level of claudication

Answer 7

0.6-0.9

(impending gangrere is 0.2-0.4)

(Impending gangrene <0.3)

Question 8

What is the 1st line investigation in chronic limb ischaemia?

Answer 8

Duplex scan

Question 9

Management of chronic limb ischaemia

Answer 9

Conservative

• Smoking cessation
• WEight loss
• Physical activity until point of maximal pain (very important because forms collaterals

Medical

• Statin (atorvostatin 80mg)
• Antiplatelet eg clopidogrel
• Antihypertensive (BP control)
• Diabetic control - good glycaemic control

Surgical - if severely crippled by symptoms

• Balloon angioplasty
• Surgical bypass
• Amputation reserved for those with critical limb ischaemia who are not suitable for other intervetnions

Question 10

What other drugs are licenced for use in chronic limb ischaemia?

Answer 10

• Naftidrofuryl oxalate - vasodilator

Question 11

What are features of critical limb ischaemia?

Answer 11

• Rest pain in foot >2 weeks
  
  • ​Releived by hanging legs over side of bed at night.
• Ulceration
• Gangrene
  
  • ​Dry - tissue necrosis without infection
  • Wet - tissue necrosis with infection
• Other = erectiale dysfunction (Leriches syndrome - triad of claudication, impotence and absence of gangrene)
  
  • Aorto-illiac disease
  • Impotency and buttock claudication

Question 12

What ABPI is suggestive of critical limb lischaemia?

Answer 12

<0.5

Question 13

What is the management of critical limb ischaemia?

Answer 13

Intial

• Morphine - pain
• Anti-emetic
• Laxatives

Surgical bypass

• Somewhere to take blood from (inflow)
• Conduit (graft or vein)
• Somewhere for blood to go into (run- off)

Amputation

• If run off supply is poor, surgery can’t be done
• Prevents complications of muscle necorsis: hyperkalaemia, acidosis, ARF, cardiac arrest
• Above knee - if no femoral pulse
• Below knee - if femoral pulse

Question 14

What is gas gangrene?

Answer 14

• Typically aeroobic and anaerobic bacterial infected by clostridium found in soil
• So in WW1 wounds debrided and left open to overcome GG

Question 15

What can cause acute lumb ischaemia?

Answer 15

• Thrombus from diseased artery
• Emboli (usually from heart AG or aneurysm)
• Graft/angioplasty occlusion
• Trauma

Question 16

What are the symptoms of acute limb ischaemia?

Question 17

Investigations of acute limb ischaemia

Answer 17

Emergency! May require open surgery or angioplasty

Imaging - source of emboli

• Angiogram
• Echo
• US - aorta peripheral and femoral arteries

Question 18

Managmenet of acute limb ischaemia

Answer 18

• 1st line - heparin needed immediately

Treatment then depends on cause:

• Embolus - Is leg salvageable?
  
  • ​Y - urgent embolectomy, local thrombolysis/bypass graft
  • N - amputation
• Thrombus - Is leg salvageable?
  
  • ​Y - angiography (thrombolysis/angioplasty/bypass surgery)
  • N - amputation