Colon and Small Bowel—Intestinal Angina
Concept
Chronic occlusion of two of the three main visceral arter- ies (celiac, SMA, IMA). Postprandial pain related to insuf- ficient blood flow 15–60 minutes after meals.
Way Question May be Asked?
“69 y/o male with history of peripheral vascular disease presents with weight loss and postprandial abdominal pain.” Don’t expect a clear description of “food fear” or weight loss. Many patients actually develop eating habits to avoid the post-prandial pain including “small meal syn- drome.” Patient may even present with UGI dysmotility or ulcers.
How to Answer?
Complete history including history of vascular diseases Complete physical exam including abdominal bruits Be sure to ask about questions that relate to abdominal
malignancy
Diagnostic Tests
Cardiac workup (on all vascular pts)
Visceral duplex showing stenosis (high flow velocities) in celiac and SMA or reversal of flow in the hepatic artery
Gold standard = angiogram with AP and lateral views
Endovascular techniques an option for high risk pts Be able to describe operative technique:
Transabdominal approach through midline incision Antegrade bypass from distal thoracic aorta
Bifurcated graft between the supraceliac aorta (approached through the gastrohepatic omentum and both the celiac and the SMA)
Bifurcated 12 × 7 mm graft
Left limb anastomosed to celiac trunk in end to side fashion with heel on celiac trunk and toe as onlay path onto common hepatic
End to end bypass to SMA done below the body of the pancreas
Aorta-SMA graft commonly placed behind the common hepatic artery
Must divide crus of right diaphragm to expose supaceliac aorta
Must divide Ligament of Trietz to expose SMA infrapancreatically
Good communication with anesthesiologist before supraceliac clamping to permit adequate volume loading and unclamping for expected decrease in BP A retrograde bypass is another option from a healthy infrarenal aorta and the SMA distal to its occluded segment Could also place a straight graft from infrarenal aorta to
the SMA distal to its area of occlusion IMA reconstruction increases post-op morbidity
Follow pt with Duplex U/S prior to hospital discharge and closely post-op (every 6 months)
Common Curveballs
Can’t get a mesenteric duplex at your hospital Questions about surgical reconstruction of IMA Bowel injury and can’t use artificial graft Pt will have other pathology on initial ex lap Pt has had prior abdominal surgery
Pt has graft thrombosis post-op Pt has acute MI
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In work-up for chronic mesenteric ischemia, pt develops acute mesenteric ischemia with bowel necrosis
Pt has post-op hepatic or renal failure secondary to supraceliac aortic cross clamp time (tolerance is typ- ically less than 1 hr)
Strikeouts
Not ruling out malignancy in pt with abdominal pain and wt. loss
Not being able to describe operative technique
Not obtaining angiogram
Not performing appropriate pre-op workup/clearance in pt with obvious vascular disease
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