Acute Limb Ischaemia Management

Question 1

What is the primary distinction between embolic and thrombotic Acute Limb Ischaemia (ALI)?

Answer 1

They are treated differently and thrombotic ALI provides more time for the body to build up collaterals and carries a better prognosis.

Question 2

What are the main causes of thrombotic ALI?

Answer 2

• PAD
• Thrombophilia
• Hypovolaemia / Hypotension
• Malignancy

Question 3

What percentage of ALI cases are due to embolism?

Answer 3

10-15%

Question 4

What are common sources of emboli in ALI?

Answer 4

• Prostheses (heart valves or bypass grafts)
• Aneurysms (especially popliteal or abdominal aortic aneurysms)
• Mural thrombus from recent myocardial infarction

Question 5

What are the 6 P’s of acute ischaemia?

Answer 5

• Pain
• Pallor
• Pulselessness
• Perishingly cold (poikilothermia)
• Paraesthesia
• Paralysis

Question 6

What conditions are included in the differential diagnosis of ALI?

Answer 6

• Chronic Limb Ischaemia (CLI)
• Acute Deep Vein Thrombosis (DVT)
• Peripheral neuropathy
• Compartment syndrome
• Thromboangiitis obliterans (Buerger’s disease)

Question 7

What bedside investigations are recommended for ALI?

Answer 7

• Duplex ultrasound / Doppler (of both limbs)
• ECG (to check for atrial fibrillation)

Question 8

What laboratory tests are included in the assessment of ALI?

Answer 8

• Full Blood Count (FBC)
• Urea & Electrolytes (U&E)
• Liver Function Tests (LFTs)
• Coagulation profile
• Group and save
• Venous Blood Gas (VBG) - lactate for severity of ischaemia
• Thrombophilia Screen (considered)

Question 9

What is the classificaiton system for limb viability in ALI?

Answer 9

Rutherford Classification

Question 10

What is the recommended systemic anticoagulation for ALI?

Answer 10

IV heparin 5000 unit bolus, then IV 1000 unit/hour infusion.

Question 11

Complete arterial occlusion will lead to irreversible tissue damage within ____ hours.

Answer 11

Complete arterial occlusion will lead to irreversible tissue damage within 6 hours.

Question 12

What is the aim for aPTT in heparin treatment?

Answer 12

60-90 seconds.

Question 13

What is a potential complication of heparin use?

Answer 13

Heparin-induced thrombocytopenia after ~5-10 days of treatment.

Question 14

What is the first-line treatment for thrombotic ALI if the limb is viable?

Answer 14

Local intra-arterial thrombolysis.

Other: surgical thrombectomy, percutaneous mechanical thrombus excretion, bypass surgery

Question 15

What is the first-line treatment for embolic ALI if the limb is viable?

Answer 15

Embolectomy with a balloon (Fogarty) catheter.

Stop heparin 4 hours beforehand

Other: percutaneous catheter-directed thrombolysis, bypass surgery

Question 16

What are potential complications of Embolectomy?

Answer 16

Embolectomy with a Balloon (Fogarty) catheter
Complications:
* Pseudoaneurysm
* AV fistula
* Arterial dissection
* Arterial perforation

Stop heparin 4 hours beforehand