Abdominal Aortic Aneurysm Flashcards
What is the definition of an aneurysm?
Dilatation of a vessel by more than 50% of its normal diameter.
What is a true aneurysm?
If vessel wall is intact i.e. all 3 layers.
What is a false aneurysm?
Breach in vessel wall (surrounding structures act as vessel wall).
What are the 3 morphologies of aneurysms?
Saccular (look like sacs), fusiform (bulge), mycotic (arises secondary to an infectious process, involving all 3 layers of artery, artery expands rapidly).
What part of the blood vessel is affected in an aneurysm?
Tunica media.
What is the clinical presentation of symptomatic AAA?
Pain (may mimic renal colic), trashing (clots moving down the distal arteries), rupture.
What is the clinical presentation of ruptured AAA?
Sudden onset epigastric/central chest pain, may radiate through to back, may mimic renal colic, collapse.
What would you find on examination of a ruptured AAA patient?
May look well, hypo/hypertensive, pulsatile, expansile mass may be tender, transmitted pulse, peripheral pulse.
What is the most and least fatal AAA?
Most: free intra-peritonieal. Least: retroperitoneal (contained rupture).
When would you intervene in an AAA?
Symptomatic. Asymptomatic and size >5.5cm AP diameter or expansion of >0.5cm in 6 months or >1cm in a year.
What would you do for AAAs that do not need intervention?
Surveillance.
What are the 2 imaging techniques to look at an AAA?
Duplex ultrasound and CT scan (arterial phase).
What can a duplex ultrasound tell us about an AAA?
If there is one, its AP diameter and involvement of iliac arteries.
How is a CT scan done in AAA?
IV contrast, commence imaging when contrast is in arterial system.
What info does a CT scan give about aneurysm morphology?
Shape, size, iliac involvement, if it has ruptured. Allows for management planning.
