Acute and Chronic Limb Ischaemia

Question 1

What is Acute limb ischaemia?

Answer 1

Sudden decrease in limb perfusion that threatens the viability of the limb

Question 2

What are the 3 different types of Limb Ischaemia based on onset?

Answer 2

=> Acute - iscahemia within 14 days
=> Acute on chronic - worsening signs and symptoms for 14 days
=> Chronic - Ischaemia is stable more than 14 days

Question 3

How is Acute Limb Ischaemia categorised based on severity?

Answer 3

=> Incomplete - limb not threatened
=> Complete - limb threatened. Loss of limb if no intervention within 6 hours
=> Irreversible - requires amputation

Question 4

What are the causes of Acute limb Ischaemia?

Answer 4

• Thrombosis
• Embolism
• Graft/ stent occlusion
• Trauma
• Aortic Dissection

Question 5

What is the clinical presentation of Acute limb Ischaemia?

Answer 5

• Pale
• Pulseless
• Perishingly cold
• Painful
• Paraesthesia
• Paralysis

Question 6

What are the investigations in suspected Acute limb Ischaemia?

Answer 6

=> Colour Duplex Ultrasound
- 1st line

=> MR/CT aniography performed prior to any intervention

Question 7

What is the emergency management of Acute limb Ischaemia?

Answer 7

• May require urgent surgery or angioplasty

=> Treatment options if cause is embolic:

• surgical embolectomy
• local thrombolysis

=> Both procedures require anticoagulation with heparin after

Question 8

What is Chronic limb Ischaemia?

Answer 8

• Peripheral Artery Disease that results in symptomatic reduced blood supply to limbs

Ankle Brachial Pressure index:
Normal = 1.0-1.2
PAD = 0.5-0.9
Critical limb Ischaemia = (< 0.5) or Ankle Systolic Pressure < 50 mmHg

Question 9

What are the risk factors of Chronic limb Ischaemia?

Answer 9

=> Modifiable:

• Smoking
• Hypertension
• Diabetes
• Hyperlipidemia
• Reduced exercise

=> Non-modifiable:

• FH and PMH
• Male
• Age
• Genetics

Question 10

What is the clinical presentation of Chronic Limb Ischaemia?

Answer 10

• Intermittent Claudication
• Rest pain
• Ulceration
• Gangrene
• Increased cap refill time
• Muscle atrophy
• Decreased Burger’s Angle

=> Rest pain, ulceration, gangrene are features of critical limb ischaemia

Question 11

What are the causes of Chronic Limb Ischaemia?

Answer 11

• Trauma
• Atherosclerosis (main cause)
• Burger’s Disease
• Subclavian steel syndrome

Question 12

What is the classification of Chronic Limb Ischaemia?

Answer 12

FONTAINE CLASSIFCATION SYSTEM

=> Stage I
- Asymptomatic

=> Stage II
- Intermiettent Claudication (usually aching or burning pain while walking which is relieved by rest, and not present at rest)

=> Stage III
- Ischaemic rest pain

=> Stage IV
- Ulceration, gangrene, or both

Question 13

What is Critical limb Ischaemia?

Answer 13

• Grade 3 or 4 on the Fontaine Classification System
• Characterised by burning pain at night relieved by hanging legs over bed

=> Features should include 1 or more of the following:

• rest pain in foot for more than 2 weeks
• ulceration
• gangrene

=> Patients often report than hanging legs out of bed at night often relieves the pain

Question 14

What are the investigations in suspected Chronic limb Ischaemia?

Answer 14

=> Duplex Ultrasound 1st line

=> MR angiography performed prior to any intervention

=> Bloods - FBC, CRP/ESR

=> ECG

Question 15

What is the management of Chronic limb Ischaemia?

Answer 15

• Quit smoking
• Treat co-morbidities like hypertension, DM, obesity
• All patients should be taking statins and clopidogrel (instead of aspirin)
• Supervised exercise programmes
• Encourage patients to exercise to the point of maximum pain
• Vasoactive drugs - Naftidrofuryl

Question 16

What are the interventions taken when conservative management fails?

Answer 16

• Percutaneous Transluminal angioplasty
• Surgical reconstruction
• Amputation

Question 17

What is the assessment of Intermittent Claudication?

Answer 17

• Check the pulses
• Perform ABPI
• Duplex ultrasound first line
• MR angiography should be performed before any intervention