Chap 151-154 Mesenteric

Question 1

In embryology, what gives rise to the abdo aorta?

Answer 1

primitive dorsal artery

Question 2

In embryology, what gives rise to the celiac?

Answer 2

10th segmental branch

Question 3

In embryology, what gives rise to the SMA?

Answer 3

11th segmental branch

Question 4

In embryology, what gives rise to the IMA?

Answer 4

21st segmental branch

Question 5

What are the branches of the celiac?

Answer 5

left gastric
splenic
common hepatic

Question 6

What is the most frequent anatomic variation of the celiac?

Answer 6

hepatic arises from SMA or directly from aorta

Question 7

What are the branches of the SMA?

Answer 7

PDA
middle colic
right colic
ilieocolic
third order branches

Question 8

What are the branches of the IMA?

Answer 8

sigmoidal branches
left colic (becomes marginal artery)

Question 9

What are SMA and IMA connections?

Answer 9

marginal artery
meandering artery
sigmoidal branches lead to L and R rectal arteries which collateralize with branches of hypogastric

Question 10

What are SMA and IMA connections?

Answer 10

marginal artery 
meandering artery (l colic to middle colic)

Question 11

How does percentage of blood flow in the bowels change with eating?

Answer 11

10% of CO with shock
25% at rest
35% after large meal

Question 12

What do waveforms of the SMA look like during fasting and postprandial?

Answer 12

high arterial resistance with low diastolic flow

low-resistnace throughout both systole and diastole

Question 13

What is NOMI?

Answer 13

Impaired intestinal perfusion in absence of thromboembolic occlusion
10% of mesenteric ischemia

Question 14

What causes NOMI?

Answer 14

vasospams in arteries that supply mucosal and submucosal layers in SMA distribution

Question 15

What are angiogrpahic findings for NOMI?

Answer 15

Narrowing of the origins of multiple branches of SMA Alternate dilation and narrowing of intestinal branches (string of sausages)
Spasm of mesenteric arcades
Impaired filling of the intramural vessels.

Question 16

What are RF for NOMI?

Answer 16

low flow states
hypovolemia
systemic vasoconstrictirs
AI
CPB
reperfusion injury

Question 17

What is treatment for NOMI?

Answer 17

IA infusion of vasodilator (mort 50%)
Papverine at 30-60mg/hr
Papaverine metabolized by the liver so hypotension rarely a problem

Question 18

What are celiac-sma collaterals?

Answer 18

GDA-PDA

Question 19

What are IMA-internal collaterals?

Answer 19

hemorrhoidals to internal iliac

Question 20

What are causes of visceral vessel disease?

Answer 20

Atherosclerosis most common
Fibromuscular disease
Dissection, 
neurofibromatosis
Rheumatoid arthritis
Takayasu arteritis
Giant cell arteritis
Polarteritis nodosa
Radiation injury
Systemic lupus
Buegers disease
Drugs like cocaine
Median arcuate ligament syndrome

Question 21

What is natural history of visceral vessel stenosis?

Answer 21

1/3 devel mesenteric schema within 3 years

largely asympto until at least two vessels with critical stenosis

Question 22

What is clinical presentation for CMI?

Answer 22

Food aversion
Postprandial pain 30 mins after a meal persisting for 5-6hours
Midabdo in location and crampy or dull
WL

Question 23

What velocities on duplex suggest stenosis?

Answer 23

> 70%
ESV SMA >275
ESV celiac >200

> 50%
SMA EDV>45
celiac EDV >55 or reversal hepatic flow

Question 24

What are other diagnostic test?

Answer 24

CTA/MRA

gastric tonometry

Question 25

What are positive result of gastric tonometry for CMI?

Answer 25

Reduced CO2 washout from ischemic tissue cause PCO2 to rise

Question 26

What are positive result of gastric tonometry for CMI?

Answer 26

Reduced CO2 washout from ischemic tissue cause PCO2 to rise

Question 27

What are indication for revasc for CMI?

Answer 27

symptoms some suggest 3 VD during aortic reconstruction

Question 28

What is advantages of endovascular?

Answer 28

likley shorter hospital stays, reduced M&M | probably less long-term patency

Question 29

What are open bypass strategies?

Answer 29

supracelia (tunnel retropancreatic, ant to L renal | retrograde from infrarenal aorta or CIA (right lays better)

Question 30

``` What are the results of open vs endo symptom relief? survival? M&M? restenosis rate? ```

Answer 30

same 90% for both 60% 5 year survival endo lower M&M endo higher restenosis

Question 31

What are open bypass strategies?

Answer 31

supracelia (tunnel retropancreatic, ant to L renal | retrograde from infrarenal aorta or CIA (right lays better)

Question 32

What is median arcuate ligament syndrome?

Answer 32

Fibrous edge of diaphragmatic crura croseses ant to aorta and above celiac and compresses celiac

Question 33

What is treatment for MALS?

Answer 33

division of crura with endo possibly

Question 34

What are features of embolism in acute mesenteric ischemia?

Answer 34

50% of cases 50% lodge distal to middle colic 25% are thrombosis on top of chronic disease

Question 35

What are features of AMI on X-ray?

Answer 35

Thumbprinting in advanced cases of ischemia (pneumatosis)

Question 36

What are features of AMI on CT?

Answer 36

``` Pneumatosis Vessel occlusion Hepatic venous air Lack of bowel wall enhancement Free ait Solid organ infarct Mucosal enhacement Ascites ```

Question 37

What are techniques to examine the bowel intra-operatively?

Answer 37

``` visible/palpable pulsation in arcade doopler signals in the arcade color and appearance of the bowel serosa peristalsis bleeding from cut surfaces fluorescein perfusion fluorometer laser Doppler flowmeter ```

Question 38

What are causes of mesenteric vein thrombosis?

Answer 38

``` idopathic (primary) trauma inflam state (pancreatitis) peritonitis portal htn obesity hypersplenism thrombophilia ```

Question 39

What does bowel look like on inspection?

Answer 39

limited segment of intestinal schema with edema and reddish discolouration small bowel and mesentery

Question 40

What does bowel look like on inspection?

Answer 40

limited segment of intestinal schema with edema and reddish discolouration small bowel and mesentery

Question 41

What are treatment options?

Answer 41

if no peritonitis then AC with heparin | if peritonitis or bleeding, the ex lap, bowel resection

Question 42

What is in hospital mortality for MVT?

Answer 42

20%

Question 43

What are other therapeutic options for MVT?

Answer 43

TIPS perc transhepatic tpa thrombolysis via SMA