Abdominal Aortic Aneurysm

Question 1

What is it?

Answer 1

A permanent and irreversible dilation of the Aorta by at least 50% of its normal diameter

Question 2

Which layers does it involve?

Answer 2

True aneurysms involve all layers of the arterial wall

Question 3

What is a pseudoaneurysm?

Answer 3

When it only affects the tunica intima so blood collects within the wall of the aorta (tunica adventitia)

Question 4

What happens to the aorta it? (4)

Answer 4

degradation of elastic lamina, leukocytic infiltration, enhanced proteolysis and loss of smooth muscle cells

Question 5

What is the normal diameter of the aorta?

Answer 5

2cm

Question 6

What causes it? (4)

Answer 6

1. Atheroma
2. Trauma
3. Infection
4. Connective tissue disorders

Question 7

Is it common?

Answer 7

up to 12% prevalence in the UK, 78 per 100,000 over 70 years old

Question 8

Who does it affect?

Answer 8

It commonly affects more males

Question 9

Risk factors (11)

Answer 9

Severe atherosclerotic disease, family history, smoking, male, age, hypertension, COPD, hyperlipidaemia, trauma, infection, connective tissue disorders e.g MArfans

Question 10

Symptoms (3)

Answer 10

*usually asymptomatic, intermittent or continuous abdominal pain that radiates to the back, collapse

Question 11

Signs (5)

Answer 11

Expansile abdominal mass, tachycardia, hypotension, uretohydronephrosis, abdominal bruising

Question 12

What bloods would you do? (8)

Answer 12

FBC, Clotting, U&E, LFT, CROSSMATCH, GROUP AND SAVE, ESR, CRP

Question 13

Other investigations (6)

Answer 13

ECG, Chest xray, Lung function tests, ultrasound, CT, MRI angiography

Question 14

What is the emergency management? (8)

Answer 14

IV access, blood transfusion of Oneg, Antibiotic prophylaxis (Cef and Met), surgery to clamp the aorta and insert dacron graft, ECG, Hb, Crossmatch, Fluids

Question 15

What is the uncomplicated management? (7)

Answer 15

<5.5cm needs regular monitoring, >5.5cm consider reconstructive surgery to strengthen the aortic wall, smoking cessation, blood pressure control, statins, antiplatelet therapy, doxycycline/roxithromycin possibly reduce the size of the aneurysm, avoid driving

Question 16

Complications (6)

Answer 16

Rupture, thrombosis, embolism, fistulae, pressure on other structures, death

Question 17

Is there a good prognosis?

Answer 17

Risk of mortality from untreated rupture is 100%, risk of rupture depends on diameter, mortality from elective repair is 2.4%