Acute Limb Ischaemia Flashcards
What is acute limb ischaemia?
Acute limb ischaemia (ALI) is a sudden decrease in blood flow to a limb, typically within 14 days, threatening tissue viability and potentially leading to limb loss.
What are the six ‘Ps’ of acute limb ischaemia?
Pain, Pallor, Pulselessness, Paraesthesia, Paralysis, and Perishing Cold.
What are the common causes of acute limb ischaemia?
Common causes include thromboembolism, arterial thrombosis, trauma, or iatrogenic injury (e.g., catheterisation or surgery).
What is the most common cause of acute limb ischaemia?
Thromboembolism, often originating from the heart (e.g., due to atrial fibrillation), is the most common cause.
What is the difference between embolism and thrombosis in acute limb ischaemia?
Embolism refers to a blood clot traveling from another location, while thrombosis occurs due to clot formation in situ, often over atherosclerotic plaques.
What are the risk factors for acute limb ischaemia?
Risk factors include atrial fibrillation, peripheral arterial disease, recent surgery, trauma, smoking, diabetes, and hypercoagulable states.
What are the symptoms of acute limb ischaemia?
Symptoms include sudden severe limb pain, numbness, weakness, and coldness in the affected limb.
What clinical signs might be present in acute limb ischaemia?
Signs include pallor, pulselessness, cold skin, reduced capillary refill, and possibly fixed mottling or necrosis in advanced cases.
What is the pathophysiology of acute limb ischaemia?
A sudden blockage of arterial blood flow leads to tissue hypoxia, acidosis, and eventual cell death if untreated.
What imaging studies are used to diagnose acute limb ischaemia?
Doppler ultrasound, CT angiography, or MR angiography can confirm the diagnosis and locate the site of obstruction.
What is the role of a Doppler ultrasound in acute limb ischaemia?
Doppler ultrasound assesses blood flow and can identify the presence or absence of pulses in the affected limb.
What are the stages of acute limb ischaemia severity?
Stages include: I (Viable), IIa (Marginally Threatened), IIb (Immediately Threatened), and III (Irreversible).
What is the management priority for a limb in stage III acute limb ischaemia?
Stage III is irreversible, and the priority is limb amputation to prevent systemic complications like sepsis and multi-organ failure.
What are the treatment options for acute limb ischaemia caused by an embolism?
Treatment options include urgent embolectomy, anticoagulation, and thrombolysis.
What are the treatment options for acute limb ischaemia caused by thrombosis?
Options include angioplasty, bypass surgery, thrombolysis, or anticoagulation depending on the severity and underlying condition.
What is the first-line medical treatment for acute limb ischaemia?
Intravenous heparin is used to prevent further clot propagation.
What is an embolectomy?
An embolectomy is a surgical procedure to remove an embolus from an artery and restore blood flow.
What are the complications of untreated acute limb ischaemia?
Complications include tissue necrosis, limb loss, sepsis, and death.
What is the prognosis for acute limb ischaemia?
Prognosis depends on the severity and promptness of treatment. Irreversible damage can occur within 6 hours, with significant risks of amputation or death if untreated.
What are the signs of irreversible acute limb ischaemia?
Signs include fixed mottling, non-viable tissue, absent sensation, and complete paralysis.
What is the role of reperfusion therapy in acute limb ischaemia?
Reperfusion therapy, including thrombolysis or surgical intervention, aims to restore blood flow and salvage the limb.
What complications can occur after reperfusion in acute limb ischaemia?
Reperfusion complications include compartment syndrome, reperfusion injury, and hyperkalaemia, which can lead to systemic effects.
What is the role of fasciotomy in acute limb ischaemia?
Fasciotomy may be performed to prevent or treat compartment syndrome after reperfusion.
What lifestyle modifications can help prevent acute limb ischaemia?
Smoking cessation, blood pressure control, diabetes management, and regular exercise can reduce the risk of acute limb ischaemia.
What is the long-term management of patients who survive acute limb ischaemia?
Long-term management includes anticoagulation (e.g., warfarin or DOACs), management of risk factors, and regular vascular follow-up to prevent recurrence.
