1. Amira Faour Emergency Medicine PGY2 4/3/19
AAA
Amira Faour
Emergency Medicine PGY2
4/3/19

2. Background Ruptured AAA 10th leading cause of death in M >50 US
Triad seen in 33% ruptured AAA
Abdominal pain radiating to back
Hypotension
Pulsatile abdominal mass
Dx via US, CT, MRI

3. Anatomy
Abd aorta continuation of thoracic aorta and begins at the aortic hiatus at the diaphragm
Abd aorta T12 → L4 where it divides into the common iliac arteries

4. AORTA 13CM

6. -normal aorta→ anechoic, echo-free lumen with bright white echogenic walls
-TRANSVERSE just below the xiphoid process
-get view of AORTA, IVC, VERTEBRAL BODY

7. 5 sites Proximal Mid Distal R iliac L iliac Outer wall to outer wall
Distal (just proximal to aortic bifurcation)

8. AAA Diameter >3 cm Iliac arteries >1.5 cm
Focal dilatation (1.5 times the adjacent aortic segment)
Lack of normal tapering dilatation
Intraluminal thrombus

10. THIS PIC HAS INTRALUMINAL THROMBUS
-scan from xiphoid process to aortic bifucation (near umbillicus)
-note any aneurysmal dilatation or intraluminal thrombus

11. Sagittal view to look for saccular aneurysms
USE LIVER as a window
Rotate probe 90 degrees with indicator to pts head

13. Aortic DISSECTION
HYPERECHOIC INTIMAL FLAP

15. his short (usually less than 1 cm) vessel can often be seen sonographically in the transverse plane, dividing in a “wide Y”. The fork on the patient’s right is the common hepatic artery, heading to the porta hepatis; the fork on the patient’s left, is the splenic artery. This sonographic view is known as the “seagull sign”.

16. Pearls
Transverse measurements may overestimate size of aneurysm if measured obliquely
Cylinder tangent effect
Measurement in longitudinal plane can underestimate diameter if aorta visualized tangentially or taking measurements of the side of midline

17. Note: transverse measurements may over-estimate the size of the aneurysm if the measurement is oblique

18. Pearls False + Increased gain or reverberation artifacts
Don't confuse with intraluminal thrombus
Consider lateral decubitus of cannot visualize aorta anteriorly
Bend knees while supine (decrease tension on rectus muscles)
Signs of rupture:
Intraperitoneal free fluid, retroperitoneal hematoma, lateral displacement of side where aorta is ruptured
Absence of intraperitoneal free fluid does not rule out rupturing AAA
CAN LEAK INTO THE RETROPERITONEUM CAN BE CONTAINED BY TAMPONADE AND LOCAL CLOTTING

19. R MID AXILLARY LINE CAN BE USED AS ACOUSTIC WINDOW

26. THANK YOU!

27. References
Sonosupport