Test 2: Renal and Mesenteric Flashcards
What are the mesenteric vessels?
- Celiac
- Common hepatic
- Splenic
- SMA
- IMA
What are the two vessel that form the celiac axis?
The common hepatic and splenic.
What is the first major branch of the abdominal aorta?
The celiac axis.
Where does the celiac axis arise from?
It arises off anteriorly, about 1-2 cm below the diaphragm.
What 5 things does the celiac axis supply?
- Stomach
- Duodenum
- Liver
- Pancreas
- Spleen
Where does the superior mesenteric artery arise from?
- It arises approx. 1-2 cm below the celiac axis.
- Runs anterior and parallel to the aorta.
What 4 things does the SMA supply?
- Pancreas
- Duodenum
- Small intestine
- Colon
What is the most distal branch?
Inferior mesenteric artery.
Where is the IMA located?
- Usually located approx. 1-3 cm proximal to aortic bifurcation.
- Arises from the anterior surface of the aorta at 1 o’clock.
What does the IMA supply?
- The colon
Approx. how many people are affected by common anatomical variants in the mesenteric vessel?
Approx. 20% of general population.
What is the most common (17%) mesenteric vessel variant?
Right hepatic artery originates from an artery other than celiac artery.
What are the 4 most common mesenteric anatomical variants?
- Replaced right hepatic artery originating from the SMA (10-12%)
- Replaced common hepatic originating from the SMA (2.5%)
- Common hepatic originating from the aorta (2%)
- Common origin of celiac and SMA (<1%)
What should be done for patient preparation?
- NPD after midnight
- Supine with head slightly elevated
What are some normal mesenteric doppler waveforms in the aorta?
High resistance
What are some normal mesenteric doppler waveforms in the celiac?
Low resistance
What are some normal mesenteric doppler waveforms in the SMA?
High resistance IF fasting.
What are some normal mesenteric doppler waveforms in the renals?
Low resistance.
What are some normal mesenteric doppler waveforms in the IMA?
High resistance IF fasting.
What are some indications for chronic mesenteric ischemia?
- Abdominal pain/cramping associated with eating
- Abdominal bruit
- Post-prandial pain
- Unintended weight loss
In IAC Protocol, what vessels must be assessed?
- Abdominal aorta
- Celiac axis
- Common hepatic artery
- Splenic artery
- SMA origin
- Proximal SMA
- IMA
What must be documented in a mesenteric duplex: IAC protocol?
- Highest PSV
- Document patency of celiac and SMA
- Document any conditions of the aorta or great vessels
What is the mesenteric duplex IAC protocal in the celiac artery and what should be documented?
- Document patency
- Look for high velocities or distrubed flow in the celiac, splenic or hepatic artery.
- Note common hepatic flow direction
- Measure PSV in celiac, splenic and hepatic arteries.
- Document any flow distrubances
- If stenotic abnormal flow signals are found in the proximal celiac axis, have the patient take a deep breath and hold his breathwhile you take another sample in the celiac axis.
What is the mesenteric duplex protocol for the SMA?
- Document patency
- Look for high velocities or distrubed flow along as much of the artery as can be seen.
- Measure PSV in vessels and in any stenotic areas: assess post stenotic flow pattern.
What is the mesenteric duplex protocol in the IMA?
- Locate the IMA if possible
- Document the patency.
- Measure the PSV
- Document any stenosis and post stenotic flow pattern.
What does a normal SMA and IMA signal look like?
High resistance.
What does a low resistance signal in the SMA and IMA indicate in a FASTING patient?
Mesenteric ischemia.
What indicates a celiac artery stenosis?
- PSV measuring >200 cm/s
- Post-stenotic turbulence
What indicates a celiac artery occlusion?
- Absence of flow
- Flow in the common hepatic artery is frequently reversed.
What is normal in the celiac artery?
- <125 cm/s
- Low resistance waveform.
What indicates greater than/ equal to 70% stenosis?
- >200 cm/s
What is normal in the SMA?
- <125 cm/s
- High resistance waveform.
What is abnormal that indicates greater than/ equal to a 70% stenosis?
- >275 cm/s
What indicates an occlusion in the SMA?
- Absence of flow prominent IMA may indicate hemosignifcant SMA stenosis or occlusion.
What indicates a celiac occlusion?
- Absence of flow
- Reversed common hepatic artery flow
What is the diagnostic criteria and interpretation in the IMA?
- No commonly accepted velocity criteria
- Velocities and doppler waveforms dependent on celiac artery and SMA
- Assessing for post-stenotic turbulence when elevated velocities are obtained is crucial.
Why might a progressive occlusion of the mesenteric vessels may be relatively asymptomatic?
The gut has remarkable ability to develop compensatory collateral flow.
When mesenteric symptoms do occur, what is expected?
2 out of the 3 major splanchnic vessels are usually occluded or highly stenosis.
What are some risk factors for mesentric pathology?
- Hypertension
- Diabetes
- Smoking
- High cholestrol.
- Female
- Age
Who is more prone susceptible to MALS?
More common in younger women
Who is more susceptible to chronic mescenteric ischemia?
Elderly.
What are some mesenteric duplex indications?
- Abdominal pain/cramping associated with eating.
- Abdominal bruit
- Post-prandial pain
- Unintended and/or unexplained weight loss.
- Visceral Artery aneurysm
- Other gastrointestinal symptoms
- Post-op
What is the cause of chronic mescenteric ischemia?
Atherosclerosis and thrombosis.
What is the cause of acute mesenteric ischemia?
Embolism
What is the cause of non-occlusive disease?
Low cardiac output
What is the cause of mesenteric vein thrombosis?
Hypercoaguability
What is the cause of MALS?
The celiac trunk is compressed by the median arcuate ligament which can cause subsequent fibrosis of lumen may occur.
What is the clinical manifestations of acute mesenteric ischemia?
Sudden onset of abdominal symptoms and rapid progressions to a life-threatening conditions.
What are the symptoms of acute mesenteric ischemia?
- Abdominal pain
- Bowel evacuation
- Abdominal distention
- fever
- dehydration
- GI bleeding
- Shock
- Acidosis
- Death
What is usually involved in acute mesenteric ischemia?
SMA
What is the morality rate of acute mesenteric ischemia?
70%
What vessels does chronic mesenteric ischemia?
It typically involves atleast 2 of the 3 major vessels.
What are the symptoms of chronic mesenteric ischemia?
- Unintended weight loss
- Fear of food
- Post-prandial pain
- Patient avouds food because of pain
- Diarrhea
What is MALS caused by?
It is caused by compression of the median arcuate ligament.
How does MALS normalize?
With a deep breath (inspiration)
MALS is typically found in who?
Younger women.
What should you do whenever you find an abnormal celiac signal?
Have the patient take a deep breath and then evaluate the celiac again with them holding their breath.
What two types of doppler waveforms should you compare in MALS?
- Deep inspiration
- Complete exhalation
Descrie visceral aneurysm?
- Rare
- Most common site is the splenic artery
Describe a dissection?
- Causes include:
- athersclerosis
- FMD
- mycotic infection
- trauma
- connective tissue disorders
- Most common site is SMA
What PSV in the celiac artery indicate a ≥70% stenosis?
PSV ≥ 200 cm/s
What PSV in the SMA indicates a ≥70% stenosis?
PSV ≥ 275 cm/s
What EDV in the celiac artery indicates ≥50% stenosis?
EDV ≥55 cm/s
What EDV in the SMA indicates a ≥50% stenosis?
EDV ≥45 cm/s