Vascular

Abdominal Aortic Aneurysm (AAA)

Localized dilation of ABD aorta > 1.5 x normal diameter (~2 cm) but > 3 cm ➔ dx of aneurysm
↑ risk of thrombus
> 5 cm ➔ ↑ risk of rupture
RF: ♂> ♀, atherosclerosis/↑ cholesterol, smoking, ↑ age, family hx, C.T. dzs (marfan), hx of aortic graft (hx of dissection)
- Atherosclerosis ➔ inflammation ➔ proteases degrade tunica media ➔ weak aorta
- Below renal arteries (infra renal) MC because ABD aorta doesn't have vasculature that feeds aorta (like it does higher up)

Incidental finding and ASX or... ABD/low back pain, flank pain/renal colic (can mimic kidney stone sx)
Palpable ABD mass (may be pulsating), ABD bruit
Hypotension/syncope and ecchymotic flank means they ruptured
Retroperitoneal bleeding (associated with hemorrhagic pancreatitis or AAA)
- ➔ Grey turner sign - flank ecchymoses (Turn them on their side and they're grey)
- Cullen sign - peri-umbilical ecchymoses (cUllen - umbilical)
Aorta-enteric fistula ➔ acute GI bleed presentation with hx of aorta repair
Rupture into IVC or iliac veins ➔ acute venous HTN ➔ ruptured bladder vessels ➔ hematuria

ABD US
- ♂ smoking hx 65-75yo (consider in ♂ & ♀ 65-75 yo with family hx)
  - > 2.5 cm - 2.9 cm: US q 10yr
  - AAA 3.0 - 3.9 cm: US q 3yrs
  - AAA 4.0 - 4.9 cm: US q 1yr
  - AAA 5.0 - 5.4 cm: US q 6mo

AAA suspected but no sx ➔ ABD US (usually... best initial and confirmatory test)
Pt has sx but is stable ➔ CT with IV contrast or angiography
Pt is sick (rupture) ➔ surgery within 90 mins
- Can do focused bedside US in non-obese pts but don't delay tx if presentation says ruptured/pending rupture

3.0 cm - 5.4 cm ➔ β-blockers, smoking cessation, repeat US (intervals determined by size)
Surgery - Immediate Endovascular repair (EVAR) > open surgical repair (OSR)
- Unstable pt (rupture)
- > 5.5 cm or ↑ diameter of 0.5 cm

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