Specialists Without Borders
Seminar in Surgery
Rwanda, September 2010
Acute Limb Ischaemia
John Gan
Vascular Surgeon
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• Acute ischaemia
• Chronic ischaemia
– The six Ps
• Pain
• Paralysis
• Pallor
• Pulseless
• Parasthaesia (Pins and needles)
• Poikylothermia (Perishingly cold)
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Claudication
Rest pain
Ulcers
Gangrene
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• Acute limb ischaemia
– Challenging problem
– Mortality rate 25%
– Limb amputation rate 35%
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• Acute Limb Ischaemia
– Sudden arterial occlusion
– Tissue hypoperfusion
– Ischaemic symptoms
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• Acute limb ischaemia
– Rapid occlusion leads to severe
ischaemia
• the 6 Ps
– Slow onset occlusion allows
collateral formation and mild
ischaemia
• claudication
• rest pain
• gangrene
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• Acute limb ischaemia
– 4 to 6 hours ischaemic time
causes irreversible effects
– Propagation of thrombus
– Occlusion of outflow vessels
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• Acute limb ischaemia
– Compartment syndrome
– Reperfusion injury
– Systemic effects
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• Common causes
– Embolism
– Thrombosis
– Trauma
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• Other causes
– Thrombophilia
– Other vasculopathy
• Aneurysm
• Compression syndromes
• vasculitis
– Intra arterial injection
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• Presentation
– Emergency
– Unmistakable
– The six Ps
• Pain
• Paralysis
• Pallor
• Pulseless
• Parasthaesia (pins and needles)
• Poikylothermia (perishingly cold)
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• Differential diagnosis
– Venous ischaemia
– Neurological condition
– Low flow states
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• Natural history
– Non salvageable limb
– Limb loss
– Death
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• Assessment
– History
– Examination
– Special testing
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• History
– Degree of disability
– Time factors
– Possible causes
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• Examination
– Assess the affected limb
• The 6 ps
– Compare to the “normal limb”
– Assess the whole patient
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• Examination
• The six Ps
– Pain
– Paralysis
– Pallor
• Pulseless
• Parasthaesia (pins and needles)
• Poikylothermia (perishingly cold)
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• Three groups of cases
– Viable
– Threatened
• Salvageable with immediate
treatment
• Salvageable with timely treatment
– Non salvageable
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• Viable
– Limb still warm
– Movement and sensation intact
– Pain moderate or resolving
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• Threatened
– immediate treatment required
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•
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•
Six Ps present
Absent movement
Absent sensation
Less than 4 to 6 hours
• Threatened
– timely treatment required
• Moderate pain
• impaired movement
• impaired feeling
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• Non salvageable
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Six Ps
greater than four to six hours
Fixed staining of skin
Woody feel to limb
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• Degree of ischaemia and causation
– Embolism
– Trauma
– Acute on chronic
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• Special testing
– Hand held doppler
– Duplex ultrasound
– Angiography
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• Management
• Viable cases
– Observation
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• Management
• Non salvageable cases
– Amputation
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• Management
• Threatened cases
• Revascularisation
– Embolectomy
– Bypass
– Thrombolysis
• Compartment syndrome
– fasciotomy
• Systemic supportive therapy
– Cardiac/respiratory/renal
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• Summary
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Arterial occlusion
Causation
Emergency
Six Ps
Three categories
Appropriate treatment
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1. Acute occlusion of a previously normal artery results in severe ischaemic
symptoms because:
a.
b.
c.
d.
it occurs without warning
occlusion of a normal artery is rare
there are few collateral vessels to supply the limb
embolism cannot occur in a diseased artery
2. Compartment Syndrome occurs in the ischaemic limb:
a. leading to a reduction in pain
b. because ischaemic muscle shrinks
c. when muscle is re-perfused after a period of ischaemia
d. due to reduced blood flow
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3. Acute limb ischaemia caused by embolism occurs due to:
a. acute thrombosis of a chronic stenosis
b. occlusion of an artery when clot travels from one site to another
c. thrombosis of an aneurysm
d. clot moving from the venous to arterial circulation in some cases
4. Features of an acutely ischaemic limb requiring immediate treatment include:
a. complete paralysis
b. complete sensory loss
c. absent pulse and Doppler signal
d. all of the above