Acute limb ischaemia

Acute Limb Ischaemia

Arterial thrombosis causing cyanosis

Acute occlusion of the axillary artery

Angiograph before and after thrombolytic therapy in a case of thrombosis on the hand

Acute limb ischaemia (ALI) is a sudden decrease in blood flow to a limb, threatening its viability. It is a medical emergency that requires prompt diagnosis and treatment to prevent tissue necrosis and potential amputation.

Causes

Acute limb ischaemia can result from several causes, including:

• Embolism: A blood clot or other debris travels through the bloodstream and lodges in a limb artery.
• Thrombosis: A blood clot forms in a limb artery, often due to underlying atherosclerosis.
• Trauma: Physical injury to a limb can damage blood vessels, leading to ischaemia.
• Aortic dissection: A tear in the aorta can extend into limb arteries, reducing blood flow.

Symptoms

The classic symptoms of acute limb ischaemia are often referred to as the "six Ps":

• Pain
• Pallor
• Pulselessness
• Paresthesia
• Paralysis
• Poikilothermia (coolness)

Diagnosis

Diagnosis of acute limb ischaemia involves a combination of clinical assessment and imaging studies. Common diagnostic tools include:

• Doppler ultrasound: To assess blood flow in the affected limb.
• Angiography: Provides detailed images of blood vessels to identify blockages.
• Magnetic resonance imaging (MRI) or computed tomography (CT) angiography: Non-invasive imaging techniques to visualize blood vessels.

Treatment

The treatment of acute limb ischaemia aims to restore blood flow and prevent tissue damage. Options include:

• Thrombolysis: Administration of drugs to dissolve blood clots.
• Surgical embolectomy: Removal of the embolus or thrombus through surgery.
• Bypass surgery: Creating a new pathway for blood flow around the blocked artery.
• Amputation: In severe cases where tissue death has occurred, amputation may be necessary.

Prognosis

The prognosis of acute limb ischaemia depends on the severity and duration of the ischaemia, as well as the underlying cause. Prompt treatment can significantly improve outcomes and limb salvage rates.

Prevention

Preventive measures focus on managing risk factors for vascular disease, such as:

• Smoking cessation
• Blood pressure control
• Cholesterol management
• Diabetes management

Related pages

• Peripheral artery disease
• Chronic limb-threatening ischaemia
• Vascular surgery
• Thrombosis

• 
  Arterial thrombosis causing cyanosis
• 
  Acute occlusion of axillary artery
• 
  Angiograph before and after thrombolytic therapy in a case of thrombosis on the hand