Surgery - Aaa

Front 1

What is the M:F ratio of AAA?

Back 1

4:1

Front 2

Who is at highest risk for AAA?

Back 2

White Males

Front 3

What is the most common etiology of AAA?

Back 3

Atherosclerotic in 95%

Inflammatory in 5%

Front 4

What is the most common site of AAA?

Back 4

Infra-renal (95%)

Front 5

What is the incidence of AAA in adults >60?

Back 5

5%

Front 6

What % of patients with AAA have a peripheral arterial aneurysm?

Back 6

20%

Front 7

What are the risk factors for AAA?

Back 7

1. Atherosclerosis
2. Smoking
3. FH
4. HTN
5. Male gender
6. Advanced age
7. CT disease (Marfan, Ehlers Danlos)

Front 8

What are the symptoms of AAA?

Back 8

most are ASYMPTOMATIC and discovered during routine abdominal exam by PCP or US/CT done for other reasons

Sx's range from vague epigastric discomfort to back and abdominal pain

Front 9

What are the signs of AAA rupture? (triad)

Back 9

1. Pulsatile mass on abdominal exam
2. Abd pain
3. Hypotension

Front 10

By how much do AAA's grow each year?

Back 10

about 3-4 mm BUT larger AAA's grow faster

Front 11

Why do larger AAA's rupture more often and grow faster than smaller AAA's?

Back 11

Laplace's law: wall tension = pressure X diameter

Front 12

What is the risk of rupture per year based on AAA diameter size?

Back 12

< 5 cm = 4%

5 - 7 cm = 7%

> 7 cm = 20%

Front 13

Where does the Aorta bifurcate into the Common Iliac Artery?

Back 13

Umbilicus = palpate between the xiphoid process and umbilicus

Front 14

What is the DDx of AAA?

Back 14

-Acute pancreatitis
-Aortic dissection
-Mesenteric ischemia
-MI
-perforated ulcer

Front 15

What are the diagnostic tests for AAA?

Back 15

use US to follow clinically

Contrast CT and Arteriogram

Front 16

What is the limitation of Arteriogram?

Back 16

AAA's often have large mural thrombi, which result in falsely reduced diameter b/c only the patent lumen is visualized

Front 17

What are the signs of AAA on AXR?

Back 17

Calcification in the aneurysm wall, best seen on lateral view = "eggshell" calcifications

Front 18

What are the indications for surgical repair of AAA?

Back 18

1) AAA > 5 cm, if the patient is not an overwhelming high risk for surgery

2) Rupture of AAA

3) Any size of AAA with rapid growth

4) Sx's/embolization of plaque

Front 19

Describe Endovascular AAA repair

When is it used?

Back 19

Repair of AAA by a femoral artery catheter placed stents

In poor operative candidates

Front 20

Why is the graft wrapped by the native aorta?

Back 20

This reduces the incidence of Entero-graft fistula formation
-prevents the formation of a fistula between the graft and intestine

Front 21

What type of repair should be performed with AAA and iliacs severely occluded or iliac aneurysms?

Back 21

Aortobi-iliac or aortobifemoral graft replacement

Front 22

What is the treatment if the patient has abdominal pain, pulsatile abdominal mass, and hypotension?

Back 22

take the patient to the OR for emergent AAA repair

Front 23

What is the treatment if the patient has known AAA and new onset of abdominal pain or back pain?

Back 23

CT scan
1. Leak -> straight to OR
2. No leak -> repair during next elective slot

Front 24

What is the mortality rate associated with the following types of AAA treatment:
1. Elective?
2. Ruptured?

Back 24

1. < 4% operative mortality

2. ~50% operative mortality

Front 25

What is the leading cause of death postoperatively in a patient undergoing elective AAA treatment?

Back 25

MI

Front 26

What is the mean normal diameter of the aorta?

Back 26

2 cm

Front 27

What are the possible operative complications?

Back 27

1. MI
2. Atheroembolism
3. Declamping hypotension
4. ARF
5. Ureteral injury
6. Hemorrhage

Front 28

Why is colonic ischemia a concern in the repair of AAA's?

Back 28

Often the IMA is sacrificed during surgery; if collaterals are not adequate, the patient will have colonic ischemia

Front 29

What are the signs of colonic ischemia?

Back 29

Heme-positive stool
BRBPR
Diarrhea
Abd pain

Front 30

What is the study of choice to diagnose colonic ischemia?

Back 30

C-scope

Front 31

When is colonic ischemia seen postoperatively?

Back 31

usually in 1st week

Front 32

What is the treatment of necrotic sigmoid colon from colonic ischemia?

Back 32

1. resection of necrotic colon
2. Hartmann's pouch or mucus fistula
3. End colostomy

Front 33

What is the possible long-term complication that often presents with both upper and lower GI bleeding?

Back 33

Aorto-enteric fistula

Front 34

What are other possible post-op complications? (5)

Back 34

ED due to sympathetic plexus injury

Retrograde ejaculation

Aortovenous fistula to IVC

Graft infection

Anterior Spinal Syndrome

Front 35

What is the Anterior Spinal Syndrome? (4)

Which artery is involved?

Back 35

1. Paraplegia
2. Loss of bladder/bowel control
3. loss of pain/temp sensation below level of involvement
4. sparing of proprioception

Artery of Adamkiewicz = supplies the anterior spinal cord

Front 36

What are the MC bacteria involved in Aortic Graft infections? (2)

Back 36

1. S. aureus
2. S. epidermidis (usually late)

Front 37

How is a graft infection and an Aorto-enteric fistula treated?

Back 37

Extra-anatomic bypass with resection of the graft
-axillofemoral bypass graft (graft not in a normal vascular path): usually the graft goes from the axillary artery to the femoral artery and then from one femoral artery to the other (fem-fem bypass)

Front 38

Which vein crosses the neck of the AAA proximally?

Back 38

Left Renal Vein

Front 39

What part of the small bowel crosses in from of the AAA?

Back 39

Duodenum

Front 40

Which large vein runs to the left of the AAA?

Back 40

Inferior Mesenteric Vein

Front 41

Which artery comes off the middle of the AAA and runs to the left?

Back 41

IMA

Front 42

Which vein runs the RIGHT common iliac artery?

Back 42

LEFT commmon iliac vein

Front 43

What three things runs anterior to the Common Iliac bifurcation?

Back 43

1. Ureter
2. Testicular/Ovarian Artery
3. Testicular/Ovarian Vein