Flashcards in Vascular Emergencies Deck (25):
What is acute lower limb ischaemia?
Previously stable limb with sudden deterioration in arterial supply resulting in rest pain and/or other features of severe ischaemia of less than 2 weeks duration.
What are the consequences of acute lower limb ischaemia?
Complete - extensive tissue necrosis within 6 hours of onset unless arterial circulation is restored. Needs assessment and prompt management to prevent amputation.
What are the clinical features of acute arterial occlusion?
Intense spasm in distal arterial tree. Limb appears marble white. Mottling as skins fills with deoxygenated blood after spasm relaxes. If the mottling blanches, the limb is salvageable.
What are the causes of acute lower limb ischaemia?
Embolism - AF, mural thrombosis, vegetations, proximal aneurysms, atherosclerotic plaque.
Thrombosis - atherosclerosis, popliteal aneurysm, graft closure, thrombotic conditions.
Dissection, trauma, external compression.
What are the clinical features suggestive of acute embolism?
Sudden onset of symptoms, known embolic source, absence of previous claudication, normal pulses in other limb.
What are the key points to cover in history of acute lower limb ischaemia?
Sudden onset symptoms? Exact duration of symptoms, 6 Ps. Underlying aetiology (cardiac disease, trauma, risk factors for atherosclerosis). Fitness for intervention.
What are the 6 P's of acute lower limb ischaemia?
Pain, pallor, perishingly cold, pulselessness, paraesthesia (early), paralysis (advanced ischaemia).
Which investigations should be done in acute limb ischaemia?
Not many as narrow margin of time for them. Baseline bloods - G+S. ECG to check for AF. Senior help to advice on whether specific tests (duplex US/angiogram) are needed.
How should acute limb ischaemia be managed?
Maximise tissue oxygenation with 15L 100% O2, IV heparin, appropriate analgesia, hypotension correction, treat cardiac condition.
What is the definitive treatment of emboli in acute limb ischaemia?
Catheter embolectomy under LA or GA.
What are the complications of revascularisation in acute limb ischaemia?
Sudden return of oxygenated blood to ischaemia muscles releases oxygen radicals -> cell injury and oedema. The oedema can lead to compartment syndrome and muscle necrosis.
How is compartment syndrome managed?
What is the management of irreversible ischaemia?
What is the sign for irreversible ischaemia of the limb?
Fixed mottling of the skin.
What are the two types of aneurysm rupture?
Intraperitoneal and retroperitoneal.
What is the survival rate of intraperitoneal ruptures of aneurysms and why?
Immediately fatal as the abdominal cavity has capacity for 23L of fluid and CO is 5L/min so quickly empties entire circulatory volume into abdomen.
What is the survival rate of retroperitoneal aneurysm ruptures and why?
Survive to get to the hospital as the leak is contained but eventually it will rupture intraperitoneally, and become fatal.
What are some presentations suspicious of AAA rupture?
Abdominal pain and vomiting, abdominal and back pain with collapse, renal colic in males >55 years.
What is the classic triad of AAA rupture?
Abdominal/back pain, pulsatile mass, hypotension.
How many patients present with the classic triad of AAA rupture?
Less than 1/3.
What are the features on examination of AAA rupture?
Pale patient, unwell, cold, sweaty; weak and thready pulse, hypotension; tender pulsatile mass a few cm above umbilicus; bleeding causing peritoneal irritation so mimics acute abdomen.
What are the differentials for AAA rupture?
MI with cardiogenic shock, massive pulmonary embolism, acute pancreatitis.
What is the initial management of AAA rupture?
Oxygen 15L/min, IV access to take blood and give fluids to keep systolic BP 100mmHg, catheterise, contact vascular surgeon.
What is the definitive treatment of ruptured AAA?
Surgical intervention - open repair or stent graft.