Acute Arterial Occlusive Disease

Question 1

What are the causes of acute arterial occlusion?

Answer 1

Embolus (40%)
Thrombus (40%)
Trauma

Question 2

What is Virchow’s Triad?

Answer 2

Factors predisposing to thrombus formation:

• Endothelial dysfunction
• Changes in blood flow
• Changes in coagulability

Question 3

What is embolic occlusion?

Answer 3

Occlusion of a vessel by a mass of material transported in the bloodstream

Question 4

Where can thromboemboli commonly arise?

Answer 4

Left atrium (AF)
LV (post MI)
Heart valves (endocarditis)
Mural thrombi (AAA)

Question 5

What are the sx of an acutely ischaemic limb?

Answer 5

Pulseless
Painful
Pallor
Perishingly Cold
Paralysis
Paraesthesia

Question 6

What sx indicate a threatened limb?

Answer 6

Paralysis
Paraesthesia
Pain on passive movement/calf squeezing

Question 7

What sx indicate a non-viable limb?

Answer 7

Fixed staining

Rigid muscles

Question 8

What is the time limit for re-establishing flow in an acutely ischaemic limb?

Answer 8

6hrs

Question 9

What is the immediate management of an acutely ischaemic limb?

Answer 9

A-E resuscitation
IV heparin
Assessment of limb - ?surgery
Urgent CT angio - thrombus vs emboli

Question 10

How should an embolic event be managed?

Answer 10

Open embolectomy +/- local thrombolysis

Ix into underlying cause

Question 11

How should a thrombotic event be managed?

Answer 11

Thrombolysis

Interval angioplasty

Question 12

What is the main complication arising from surgical management of a thromboembolic event?

Answer 12

Reperfusion injury

Question 13

What is reperfusion injury?

Answer 13

Inflammation & oxidative damage when blood flow is restored to tissue after a long period of anoxia

Question 14

How does reperfusion injury present?

Answer 14

Oedema

Compartment syndrome sx

Question 15

What are the clinical features of an embolic event?

Answer 15

Onset - Sudden, v. severe sx (no collateral)
Source - Identifiable
Pulses - Prev normal, normal contralateral
Hx - No hx of arterial disease

Question 16

What are the clinical features of a thrombotic event?

Answer 16

Onset - Insidious, less severe sx (collateral)
Source - No obvious source
Pulses - Prev decreased pulses bilaterally
Hx - Hx of IC/Stroke/MI etc.

Question 17

What are the indications for medical management of a thromboembolic event?

Answer 17

Block seems to be resolving

Good collateral circulation

Question 18

What are the indications for surgical management of a thromboembolic event?

Answer 18

No change in condition
Poor collateral circulation
Neurological changes