Abdominal Aortic Aneurysm (AAA)

Question 1

Definition of AAA

Answer 1

Permanent dilation of the abdominal aorta, exceeding 50% where diameter >3cm

Question 2

Where do AAA commonly occur and in who?

Answer 2

Typically infrarenal (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

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

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

Question 6

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

Answer 7

Asymptomatic till increased rupture risk/ruptured
(May be found incidentally)

Sudden epigastric pain radiation to flank, pulsation mass in abdo, hypo and tachy

Question 8

What could a differential diagnosis be?

Answer 8

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

Question 9

What is the treatment if not ruptured?
Conservative

Answer 9

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

Question 10

What’s the treatment for an AAA?
Not ruptured

Answer 10

Asymptomatic & <5.5cm = monitor

Symptoms, >5.5cm and/ or expanding (1cm+/y)= surgery

Question 11

What surgery would you do for a non ruptured 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, transfusion considered then surgery
AAA graft surgery, replace weakened walls with graft

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

Surgical emergency = 100% mortality if not treated immediately

Question 13

Diagnosis for AAA

Answer 13

1st + diagnostic = abdominal ultrasound (assess aorta) - cheap, easy, highly sensitive + specific