Abdominal Aortic Aneurysm (AAA)

Question 1

Definition of AAA

Answer 1

3cm or more dilation of all arterial layers
>50% normal diameter

Question 2

Where do AAA most commonly occur and in who?

Answer 2

Typically infrarenal abdo aorta (below renal arteries) in elderly men

Question 3

Risk factors for AAA
What’s the main RF?

Answer 3

Many = idiopathic
Men (at a younger age)
Smoking - biggest RF
Increased age
Hypertension
Obesity
Trauma
Family history
connective tissue disorder - marfans/ehlers danlos

Question 4

Pathology of AAA

Answer 4

Smooth muscle, elastic + structural degeneration in All 3 LAYERS OF VASCULAR TUNIC (intima, media + adventitia) with leukocyte infiltrate

Question 5

AAA
If degeneration in all 3 layers it’s called?
If not in all 3 layers it’s called?

Answer 5

All 3 = true aneurysm
Not all 3 = pseudo aneurysm (only adventitia)

Question 6

AAA
How big must the dilation be?
What happens when the dilation size increases and what must happen?

Answer 6

Dilation = 3cm+
Dilation with increased rupture risk = 5.5+ cm
Rupture = surgical emergency

Question 7

Signs and symptoms of AAA
what is seen on examination?

Answer 7

Asymptomatic till rupture
(May be found incidentally)

O/E = Pulsatile mass in abdo +/- bruits

Rupture = Sudden severe abdo/epigastric pain radiation to flank/back

Haemodynamically unstable = shock, hypotension, tachy, low GCS

Question 8

AAA
What could a differential diagnosis be?
what signs/Sx would you see instead?

Answer 8

Acute pancreatitis, typically non pulsating + more associated with Greg turner/ Cullen signs

Question 9

AAA
What is the treatment if not ruptured?
Conservative

Answer 9

CV optimisation
Manage RF (decrease smoking, BMI, BP and take statins)

Question 10

Dx of AAA?
What cm would you treat?

Answer 10

Screening for 65+ years M with single USS (abdominal ultrasound)
3cm or less = normal
3cm - 4.4cm = rescan yearly
4.5cm - 5.4cm = rescan in 3 months
5.5cm+ OR 1cm+ growth/year = 2 week vascular referral (surgery)

Question 11

What 2 surgerys can you do for AAA?
Pros /cons of each

Answer 11

EVAR (endovascular aneurysm repair)
- stent inserted via femoral/iliac artery
+ less invasive - more lost op complications

Open surgery - laparotomy
+ fewer complications - more invasive

Question 12

What is the treatment if AAA is ruptured?

Answer 12

Stabilize ABCDE, fluids
Crossmatch 6 units blood

EVAR or Open surgery (laparotomy)

20% rupture anterior = v bad
80% retroperitoneal =less bad

Question 13

complications of AAA?

Answer 13

Rupture
Direct compression

Question 14

AAA
Layers of artery?

Answer 14

insert pic