Chap 151-154 Mesenteric Flashcards Preview

Vascular Surgery > Chap 151-154 Mesenteric > Flashcards

Flashcards in Chap 151-154 Mesenteric Deck (43):
1

In embryology, what gives rise to the abdo aorta?

primitive dorsal artery

2

In embryology, what gives rise to the celiac?

10th segmental branch

3

In embryology, what gives rise to the SMA?

11th segmental branch

4

In embryology, what gives rise to the IMA?

21st segmental branch

5

What are the branches of the celiac?

left gastric
splenic
common hepatic

6

What is the most frequent anatomic variation of the celiac?

hepatic arises from SMA or directly from aorta

7

What are the branches of the SMA?

PDA
middle colic
right colic
ilieocolic
third order branches

8

What are the branches of the IMA?

sigmoidal branches
left colic (becomes marginal artery)

9

What are SMA and IMA connections?

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

10

What are SMA and IMA connections?

marginal artery
meandering artery (l colic to middle colic)

11

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

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

12

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

high arterial resistance with low diastolic flow

low-resistnace throughout both systole and diastole

13

What is NOMI?

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

14

What causes NOMI?

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

15

What are angiogrpahic findings for NOMI?

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.

16

What are RF for NOMI?

low flow states
hypovolemia
systemic vasoconstrictirs
AI
CPB
reperfusion injury

17

What is treatment for NOMI?

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

18

What are celiac-sma collaterals?

GDA-PDA

19

What are IMA-internal collaterals?

hemorrhoidals to internal iliac

20

What are causes of visceral vessel disease?

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

21

What is natural history of visceral vessel stenosis?

1/3 devel mesenteric schema within 3 years
largely asympto until at least two vessels with critical stenosis

22

What is clinical presentation for CMI?

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

23

What velocities on duplex suggest stenosis?

>70%
ESV SMA >275
ESV celiac >200

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

24

What are other diagnostic test?

CTA/MRA
gastric tonometry

25

What are positive result of gastric tonometry for CMI?

Reduced CO2 washout from ischemic tissue cause PCO2 to rise

26

What are positive result of gastric tonometry for CMI?

Reduced CO2 washout from ischemic tissue cause PCO2 to rise

27

What are indication for revasc for CMI?

symptoms
some suggest 3 VD
during aortic reconstruction

28

What is advantages of endovascular?

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

29

What are open bypass strategies?

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

30

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

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

31

What are open bypass strategies?

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

32

What is median arcuate ligament syndrome?

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

33

What is treatment for MALS?

division of crura with endo possibly

34

What are features of embolism in acute mesenteric ischemia?

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

35

What are features of AMI on X-ray?

Thumbprinting in advanced cases of ischemia (pneumatosis)

36

What are features of AMI on CT?

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

37

What are techniques to examine the bowel intra-operatively?

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

38

What are causes of mesenteric vein thrombosis?

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

39

What does bowel look like on inspection?

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

40

What does bowel look like on inspection?

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

41

What are treatment options?

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

42

What is in hospital mortality for MVT?

20%

43

What are other therapeutic options for MVT?

TIPS
perc transhepatic tpa
thrombolysis via SMA