2 Mesenteric Vasculature Flashcards
Arteries that supply bowel with blood
Splanchnic Arteries
What are the 3 splanchnic arteries?
CA, SMA and IMA
Where do the splanchnic arteries originate from?
The anterior wall of the Aorta
What does the CA (celiac artery) divide into?
Left Gastric
Splenic
Common Hepatic
What do the branches of the CA supply? (5)
Stomach Liver Pancreas Duodenum Spleen
CA Doppler waveform is _______ resistance
Low
Celiac Artery PSV Vary from ___ to __ cm/s
50-160 cm/s
Celiac Artery EDV___ cm/s?
< 55 cm/s
How man cm does the SMA originate below the CA
1-2 cm
Can the SMA and CA share a common trunk?
YES
What does the SMA supply (4)
Small intestine
Cecum
Ascending colon
part of transverse colon
Flow varys in the SMA with ?
metabolic gut activity
SMA with fasting should have ____ resistance waveform with occasional ______
High; reversal
THE SMA PSV varys from __ to ___ cm/s
110-177 cm/s
The IMA originates from the distal aorta _ to _ cm superior to bifurcation heading to the ____.
3-4; left
IMA supplies (5)
- the left half of the transverse colon
- descending colon
- iliac
- sigmoid colon
5 rectum
IMA Hard to see, but if easy may suggest ?
SMA occlusion
What is the major collateral pathway that links the CA and SMA
Pancreaticoduodenal Arcade
via branches that surround the duodenum and the pancreas
What are the major collateral pathways that links the IMA and SMA (2)
Arc of Riolan and Marginal artery of Drummond
What is a common branch for collateralization of the Arc of Riolan and Marginal artery of Drummond
The Left colic-middle Artery
Due to potential for collaterization, splanchnic arterial occlusion is often?
Asymptomatic
Stenosis/Occlusion can cause acute or chronic?
bowel ischemia
Stenosis/Occlusion is often prevented by?
collateralization
Before assessing any mesenteric vessels which vessel should be scanned
Aorta
Why should the aorta be scanned before the mesenteric vessels?
to document any narrowing or aneurysmal disease
What is the gold standard for diagnosing stenosis?
Arteriography
Stenosis greater than what diameter reduction are clinically significant
> 70%
CA PSV of what is significant?
> /= 200 cm/s
SMA PSV of what is significant?
> /= 275
What is the PSV for the IMA?
There is none
What PSV ratio of artery/aorta indicates a significant stenosis > 70%
> 3.5
When can occlusion of the CA be considered?
with reversal of flow in the GDA or CHA
gastroduodenal and common hepatic
What lies superior to the celiac artery and can potentially cause compression with respiration?
Median arcuate ligament of the diaphragm
What can also cause occlusion of CA
Atherosclerosis
The Median arcuate ligament of the diaphragm on inspiration is there obstruction?
No
The Median arcuate ligament of the diaphragm on experation is there obstruction?
Yes, stenotic appearance returns
What type of patients does the The Median arcuate ligament of the diaphragm compression is seen
younger patients
What is Acute Mesenteric Ischemia
Sudden onset of abdominal symptoms due to embolic process
Is Acute Mesenteric Ischemia can be a ________ condition
life threatening
What is the preferred method of diagnosis for Acute Mesenteric Ischemia?
CT angio
What is Chronic Mesenteric Ischemia
Characterized by post-prandial pain (after eating)
What does the patient need to do with Chronic Mesenteric Ischemia
Change their diet
What is the best method for diagnosing Chronic Mesenteric Ischemia?
Angiography
For Chronic Mesenteric Ischemia to develop is is neccessary for at least ______ to the bowel to be involved with __________
At least 2 major arteries; atherosclerosis
CA pattern of blood flow is affected post prandially? YES OR NO
NO
Because CA is not affected post prandially which vessels are scanned?
Mesenteric Arteries
Patients are scanned both ____ and ___ parandially
Pre and Post
Fasting state waveform of Mesenteric arteries are?
High resistance
The study after the patient has been given a high caloric liquid meal is then repeated after _____ -____min or sooner is symptomatic. Then compared to fasting state.
20-30min
NORMAL post prandial PSV and EDV in mesenteric arteries ?
Increase with EDV almost doubling
ABNORMAL Waveform in fasting state of mesenteric arteries? ______ resistance _____ velocities
Low resistance with high velocities
Low resistance with high velocities in fasting state is indicative of?
Mesenteric Ischemia
no need to test post food- velocities will remain high
What type of test is used to assess bowl?
exercise stress test
Why is bowel ischemia difficult to assess with duplex sonography?
It is not always due to disease in the main celiac and mesenteric arteries
(hypotension, small vessel disease, emboli or venous obstruction)
