Flashcards in Ischemic Bowel Disease Deck (30):
1
what are the 4 major causes of acute mesenteric ischemia?
SMA embolism, SMA thrombosis, nonocclusive ischemia, and mesenteric venous thrombosis
2
Why is superior mesenteric artery commonly involved with ischemic bowel disease?
due to it's angle off of the aorta
3
Causes mesenteric (arterial) vasoconstriction and venous dilation. Reduces portal venous pressure in patients bleeding from portal hypertension
vasopressin
4
Hallmark of mesenteric arterial embolism
Severe cramping abdominal pain, out of proportion of physical findings, poorly localized
5
Where are the common origins of mesenteric arterial emboli?
Thrombus from L atrium, L ventricle or cardiac valves
6
Is coagualopathy associated with mesenteric arterial thrombosis?
no, this is more common a culprit in venous thrombosis patients
7
What is the usual site of blockage for mesenteric arterial thrombosis?
SMA or celiac axis
8
Affects younger popn (48-60). Thrombosis of superior mesenteric vein or intestinal strangulation from hernia or volvulus
mesenteric venous thrombosis
9
What is different about the presentation of mesenteric venous thrombois compared to mesenteric arterial thrombosis?
longer symptom presentation-Pain diffuse and nonspecific initially, but later becomes constant
10
Major risk factor for mesenteric venous thrombosis
hypercoagulable states (75%)
11
What is the etiology of nonocclusive mesenteric ischemia?
Result of splanchnic hypoperfusion & vasoconstriction
12
What is a major risk factor for nonocclusive mesenteric ischemia?
atherosclerotic disease
13
Mortality associated with nonocclusive mesenteric ischemia
70%
14
Any patient with abdominal pain and metabolic acidosis has what condition until proven otherwise?
intestinal ischemia
15
Critically important lab for intestinal ischemia
elevated serum lactate
16
What might be present on a plain film in patients with mesenteric ischemia?
air fluid levels, dilated bowel loops, gasless abdomen
17
Gas cysts in the bowel wall. Suggestive of necrotizing enterocolitis
Pneumatosis intestinalis
18
Accumulation of gas in the portal vein and it’s branches. A variety of causes such as ischemic bowel, intra-abdominal sepsis
portal venous gas
19
First step in the evaluation of the acute abdomen
plain abdominal xrays
20
What is the preferred imaging study in the evaluation of the acute abdomen?
CT scan
21
What is necessary for evaluatio of the mucosal thickening of the bowel wall?
oral contrast
22
What can obscure the view of mesenteric vessel of a CT angiogram?
oral contrast
23
Good study for evaluation of suspected intestinal ischemia but don’t do if planning on percutaneous angiography too (excessive contrast with 2 studies)
CT angiography
24
Better at diagnosing venous occlusions
MR angiography
25
If diagnosis is fairly certain and need consideration for percutaneous treatment or for surgical planning. Can’t be used for venous occlusions
mesenteric percutaneous arteriography
26
Vasopressors that have less effect on mesentary
dobutamine, low dose dopamine, milrinone
27
What can be given at angiography directly to relieve mesentaric vasoconstriction?
papaverine
28
Gold standard diagnostic study for acute arterial ischemia
Mesenteric Angiography
29
Treatment includes : Papaverine infusion during angiography. Reverse underlying conditions. Repeat angiography can be done in 24 hrs. Surgical exploration reserved for patients with peritoneal signs
Nonocclusive mesenteric ischemia
30