(Acute & Emergency) (Surgery)

(Focus on AAA)

Overview

• AAA is a focal dilatation of the abdominal aorta to >1.5x its normal diameter or >3cm
• Majority (>90%) originate below the renal arteries (Infrarenal)
• M>F, 60-70 yrs old
• Screening Population ⇒ males >65 years old (single USS at 65)
• Risk Factors → smoking (most important RF), FH, increased age, male sex, females at greater risk of rupture, connective tissue disorders (Marfan Syndrome), atherosclerosis, hypercholesterolemia

Making Diagnosis

Clinical Features:

• Usually asymptomatic → discovered incidentally on USS or CT.
• Rupture of aneurysm is life threatening
  • Severe, central abdominal pain radiating to the back
  • Pulsatile, expansile abdominal mass
  • Shock ⇒ hypotension + tachycardia

Investigations:

• Aortic Ultrasound → Do not delay diagnosis and management of a ruptured AAA while waiting for the results of imaging (does not tell you if ruptured)
  • CT Angiogram needed to visualise a ruptured AAA
  • Ultrasound screening is offered for all men >65 in the UK to determine the diameter of their abdominal aorta