POCUS - Aorta

Question 1

Risk factors for AAA include _______________.

Answer 1

smoking, advanced age, male sex, atherosclerosis elsewhere, HLD, and HTN

FMH of AAA or connective tissue disorders can also cause AAA.

Question 2

What views are needed for an aorta study?

Answer 2

• Proximal still image transverse w/ measurements outer-to-outer
• Distal still image transverse w/ measurements outer-to-outer
• Longitudinal video demonstrating pulsations (no measurements needed longitudinal) – bonus points for seeing the celiac and SMA branches

Question 3

Most AAAs develop in which part of the aorta?

Answer 3

Above the bifurcation and beneath the renal arteries

Don’t rely solely on a proximal view.

Question 4

What is tapering in the aorta?

Answer 4

Normally the distal aorta is smaller than the proximal – usually less than 1.5 cm. If the distal aorta is larger than the proximal, particularly if it is greater than 1.5 cm, then you need to tell the patient to get a follow.

Question 5

At the bifurcation, the aorta also ___________.

Answer 5

dives deep into the pelvis

Question 6

An AAA is defined as an aorta that is greater than _______ cm.

Answer 6

3, though greater than 2.5 cm is abnormal

Those greater than 5 cm have an exponentially higher risk of rupture.

Question 7

The risk of AAA rupture is ________ in women.

Answer 7

increased

Question 8

While this is not the primary aim of the AAA screen, be sure to look for ___________ within the aorta.

Answer 8

intimal flaps

Question 9

Always label ____________.

Answer 9

proximal and distal (this is crucial to verify tapering)

Question 10

If you can’t find the aorta at first, try ______________.

Answer 10

gentle bouncing pressure for 60 seconds; often this can push the gas out of the way

Question 11

By the time of the bifurcation, the aorta should be ___________.

Answer 11

1.5 cm

Question 12

90% of AAAs occur distal to the ______________.

Answer 12

renal arteries

Question 13

For aortas, always measure _____________.

Answer 13

the outer diameter

Question 14

What artery gives the seagull sign?

Answer 14

Celiac trunk

Question 15

What artery is usually posterior to the pancreas?

Answer 15

SMA

Question 16

True or false: the origin of the SMA is inferior to the renal arteries.

Answer 16

False

Question 17

The aorta bifurcates at what external landmark?

Answer 17

Umbilicus

Question 18

Why do you need to measure the outer wall of the aorta?

Answer 18

Because of dissection and thrombus that may be outside of the inner wall

Question 19

The word ectasia means ___________.

Answer 19

widening of a lumen

Question 20

The most common morphology of AAA is what?

Answer 20

Fusiform (circumferential dilation that tapers gradually on both ends)

The other types are saccular (little outpouchings) and hourglass (two fusiform dilations adjacent to each other in the shape of an hourglass).

Question 21

Over _____% of AAAs are infrarenal.

Answer 21

90

Question 22

Why might you look at the kidneys in a patient with a large AAA who is hypotensive?

Answer 22

Retroperitoneal hematoma can present with bleeding around thee kidneys which will be seen on US.

Question 23

True or false: normal aortic diameter rules out dissection.

Answer 23

False

Dissections can present with normal diameter.

Question 24

What features of an AAA make rupture more likely?

Answer 24

• Size greater than 5 cm
• AAA in women
• Rapid rate of expansion (assuming you had a prior to compare to)