[Surgery] Abdominal Aortic Aneurysms Flashcards
what is an abdominal aortic aneurysm (AAA)?
an abnormal dilatation of the aorta >1.5x its diameter or >3cm
who is offered a 1 time ultrasound (US) screening test to look for an AAA?
all men aged 65
higher risk pts may be offered an US. what do these risks include?
- HTN
- hyperlipidaemia
- smokers
- 1˚ relative dx-ed with AAA
- CTDs e.g. Marfan’s syndrome
when is the risk of rupture high in AAAs?
if AAA is >5.5cm or if an aneurysm grows >1cm in a year
who should be considered for a repair of AAA?
- those with high risk of rupture
- all symptomatic pts (any size)
what are the key sx for AAA?
- central abdo pain
- radiates to the back
- bloating
- pulsating mass on palpation
what are the key sx of a ruptured AAA?
- severe pain radiating to the back
- visible pulsating abdomen
- circulatory compromise
you find a 3-4.4cm asymptomatic AAA on USS. mx?
yearly USS
you find a 4.5-5.4cm asymptomatic AAA on USS. mx?
3 monthly USS
you find a ≥5.5cm asymptomatic AAA on USS. mx?
consideration for repair
what are aneurysms classified as?
- pseudo
2. true
what does pseudo aneurysm mean?
collection involving the outer 2 layers
what does a true aneurysm mean?
involves all 3 layers, further classified as:
- saccular (one sided dilatation)
- fusiform (dilatation all around the vessel)
what is the most common aetiology for AAA?
atherosclerosis
⇒ shares similar risk factors to cardiac disease
what plays a large role in prevention of AAAs?
statins, anti-hypertensives and smoking cessation
what do AAA ruptures require?
category 1 surgery (pts usually unstable, 80% mortality rate)
what are the ways AAAs can be repaired?
- Endovascular Aneurysm Repair (EVAR)
2. Open repair
IVC collapse or “Halo sign” on CT. dx?
hypovolaemic shock
aneurysmal sac enlargement post-EVAR. dx?
endoleak
chest pain + connective tissue disorder e.g. Marfan’s. dx?
aortic dissection
what is the 1st line ix for an AAA?
CT angiography for a stable pt with a high suspicion of rupture
