The primary risk factors for AAA development include:
■ Increasing age
■ Family history
■ Atherosclerotic risk factors
Other predisposing factors include infection, trauma, connective tissue disease,
and arteritis.
An AAA of any size canrupture, but the likelihood with increasing size.
The most common location of rupture is to the retroperitoneum. Rupture is
associated with an 80–90% overall mortality (many patients do not even reach
the hospital).
SYMPTOMS
■ Most aneurysms are asymptomatic when discovered and become sympto-
matic when expanding or ruptured.
■ Acute pain in abdomen, back, or flank
■ Nausea and vomiting
■ Syncope or near syncope
EXAM
■ Vital signs may be surprisingly normal.
■ Hypotension and shock if rupture with significant blood loss
■ Abdominal tenderness, distension, or pulsatile abdominal mass
■ Evidence for retroperitoneal hematoma
■ Periumbilical ecchymosis (Cullen’s sign)
■ Flank ecchymosis (Grey-Turner’s sign)
■ Massive GI bleed if rupture into GI tract (aortoenteric fistula)
■ High-output heart failure if rupture into vena cava (aortocaval fistula)
DIAGNOSIS
■ The diagnosis should be suspected in any patient >50 years old presenting
with abdominal pain, flank pain, or hypotension.
■ Abdominal X-ray
■ May see curvilinear calcified outline of enlarged aorta
■ Ultrasound(see Figure 2.15)
■ 100% sensitive when aorta is visualized
■ Modality of choice in the unstable patient
■ May not be able to identify rupture, site of leak, or retroperitoneal
hematoma
■ CT(see Figure 2.16)
■ Highly sensitive
■ Requires stable patient for transport
■ Better than ultrasound at detecting rupture and retroperitoneal blood
■ MRI or aortographyare rarely indicated in the ED.
TREATMENT
■ Ruptured aneurysms require immediate surgical intervention with operative
or endovascular repair.
■ There is no such thing as a stable rupture!
■ 50% operative mortality
■ Fluid and blood resuscitation: To SBP 90–100 mmHg.
■ Thoracotomy with cross clamping of aorta: If severe hemodynamic com-
promise or cardiac arrest
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CARDIOVASCULAR EMERGENCIES
An AAA of any size can
rupture, but those >5 cm are
more likely to rupture.
The most common location of
AAA rupture =
retroperitoneum.
Cullen’s sign =periumbilical
ecchymosis.
Grey-Turner’s sign =flank
ecchymosis.
Triad of abdominal pain,
hypotension, pulsatile
abdominal mass =AAA until
proven otherwise, although
triad is rare.