Acute Limb Ischaemia

Question 1

What are important history questions for acute limb ischaemia?

Answer 1

• Any preexisting PAD/claudication/heart disease
• Any family history or signs of maliganncy

Question 1

What is acute limb ischaemia?

Answer 1

Sudden decrease in limb arterial perfusion with potential threat to limb survival with an onset of less than 2 weeks

Question 2

What are some causes of acute limb ischaemia?

Answer 2

• Thrombosis
• Embolism
• vasospasm
• External vascular compromise either from trauma or compartment syndrome

Question 3

What are the signs and symptoms of acute limb ischaemia?

Answer 3

Pain
Pulseless
Pallor/mottling
Perishingly cold
Paranesthesia - Bad sign
Paralysis - Bad sign

Question 4

What classification system is used in acute limb ischaemia?

Answer 4

Rutherford

Question 5

What is the initial management of acute limb ischaemia?

Answer 5

• Resuscitation, analgesia and place catheter
• Bloods
• ECG (Arrhythmia can be cause of ALI)
• ABG
• Chest X ray
• Anticoagulation (usually IV heparin - only if fit for GA)
• Arterial imaging (usually CT angiography)

Question 6

What is the management of acute limb ischaemia?

Answer 6

Dependent on cause:
- Thrombo-emboli is often due to AF. Urgent thrombo-embolectomy or bypass -or catheter delivered lysis (dissolves clot)
- Aneurysm. Urgent bypass with prior thrombectomy
- Trauma (posterior knee dislocation) often treated with bypass.
- Dissection. urgent treatment of dissection with stent graft

Question 7

What are complications of acute limb ischaemia?

Answer 7

• Thrombus occurring on treatment stent
• Compartment syndrome (when muscles reperfuse they can become oedematous)
• Release of substances from damaged muscle cells such as K+, H+ leading to hyperkalaemia, acidosis and AKI

Question 8

What are the signs and symptoms of compartment syndrome?

Answer 8

• Severe pain,
• Pallor
• paralysis or weakness
• Pulseless
• Paraesthesia

Question 9

What is the management of compartment syndrome?

Answer 9

• Urgent fasciotomy
• Oxygen
• Fluids
• Remove all dressings/splints
• Analgesia

Question 10

When is an acute limb ishcaemia not salvageable?

Answer 10

Rutherford stage 3 with mottling and woody muscles. Offer major limb amputation or palliative care.
Or if a patient is unstable

Question 11

What is the timeframe for salvaging an acute ischaemic limb?

Answer 11

6 hours. This is the time point where there will likely be irreversibile tissue damage