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Assessment, Sedation & Analgesia
Categorical Course - How to Do Research in Interventional Radiology: A Practical Guide for the Tinkerer in All of Us
PART II (C202) Moderator: Michael A. Bettman, MD 3:30 pm Considerations in Pediatric Patients Patricia E. Burrows, MD 3:55 pm Assessment, Sedation & Analgesia Michael A. Bettman, MD 4:20 pm
Recognition & Management of Dysrhythmias Gregory S. Ferguson, MD
4:45 pm Discussion: Contrast Reaction Scenarios Faculty
Tuesday, March 11,1997 2:30-5:00 pm Part III (C301) Moderator: John 1. Doppman, MD 2:30 pm Mesenteric Angiography (Vascular Disease, Bleeding, Tumors) Stewart R. Reuter, MD, jD Learning objectives: At the end of this session, the attendees should be able to: (1) understand the collateral pathways involved in patients with mesenteric vascular disease; (2) understand the role of angiography in the diagnosis and treatment of lower gastrointestinal bleeding; and (J) identify small bowel leiomyomas and carcinoid tumors. IN patients with celiac artery stenosis, the primary source of collateral blood flow to the organs supplied by that artery develops from the superior mesenteric artery (SNlA), primarily over the pancreatoduodenal arteries and gastroduodenal artery. The degree of celiac stenosis can be assessed by evaluating the relative filling of the hepatic and splenic arteries from the SMA. If the stenosis is 80% to 90%, the entire celiac distribution will be supplied from the SMA, and the celiac stenosis can be identified as the contrast medium passes the orifice. If less than 80%, the collateral flow from the SMA supplies the liver to varying degrees, whereas the spleen receives blood supply from the celiac artery. In patients with distal aortic occlusions, many of which also include occlusion of the inferior mesenteric artery (IMA), the SMA becomes the primary source of collateral blood flow to the pelvis and legs. The collaterals develop over the middle colic artery, left colic artery, and superior hemorrhoidal artery to the inferior hemorrhoidal branches of the internal iliac arteries. The
marginal artery of Drummond also frequently participates in this pattern of collateral flow. In patients with infradiaphragmatic IVe occlusions, the superior mesenteric and portal veins have a similar collateral function in the reverse direction.
Mesenteric Occlusive Disease Mesenteric artery occlusion may be either chronic or acute. Most chronic occlusions are caused by atherosclerosis--usually, by aortic atherosclerotic disease that impinges on the SMA or IMA orifice. Most acute occlusions are caused by emboli. Long-term gradual SMA occlusions may be identified by the collaterals that develop from the celiac axis or the IMA in a direction opposite from that described in the previous section. In patients with IMA occlusion, the SMA is the primary source of collateral blood flow to the left colon. This occurs over the middle colic and left colic arteries to the distribution of the IMA. The marginal artery of Drummond frequently participates in this collateral pattern. If both the SMA and IMA are occluded, the celiac artery and hemorrhoidal vessels may be the only collateral blood supply to the bowel. The syndrome of mesenteric ischemia probably requires that at least two major vessels be involved before the syndrome occurs because of the effectiveness of the collateral blood flow between adjacent arteries. If individual branches of the SMA or IMA are occluded, many potential collateral pathways are available over the multiple arcades that exist between adjacent mesenteric artery branches. Most emboli to the SMA lodge at branches of the mesenteric arteries, and the defect in the artery is usually readily apparent. The acuteness can be determined by the absence of collateral arteries. Although most mesenteric occlusions proceed to bowel necrosis, on occasion, adequate collateral blood flow may develop to prevent necrosis and the patient may develop a long-term occlusive pattern with collateral blood flow as described above. Nonocclusive mesenteric ischemia is an unusual cause of mesenteric occlusion. This usually occurs in elderly, hypovolemic patients and has a rather typical appearance. All of the jejunal and ileal arteries are truncated at the origins from the SMA. As the disease progresses, the arteries may develop a somewhat beaded appearance. If not detected early, this process will lead to bowel necrosis, but the process may be reversed with the infusion of vasodilatory drugs if discovered early enough. The vascular pattern of ischemic small bowel disease is hypovascularity. The SMA branches beyond the occlusion are absent. With acute mesenteric occlusions, an element of vasoconstriction is present that accentuates the hypovascularity. With the ischemic colon, on the other hand, the vasa recta may be quite hypervascular with a great deal of arteriovenous shunting. This is caused by invasion of the ischemic mucosa by the many
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PART II (C202) Moderator: Michael A. Bettman, MD 3:30 pm Considerations in Pediatric Patients Patricia E. Burrows, MD 3:55 pm Assessment, Sedation & Analgesia Michael A. Bettman, MD 4:20 pm
Recognition & Management of Dysrhythmias Gregory S. Ferguson, MD
4:45 pm Discussion: Contrast Reaction Scenarios Faculty
Tuesday, March 11,1997 2:30-5:00 pm Part III (C301) Moderator: John 1. Doppman, MD 2:30 pm Mesenteric Angiography (Vascular Disease, Bleeding, Tumors) Stewart R. Reuter, MD, jD Learning objectives: At the end of this session, the attendees should be able to: (1) understand the collateral pathways involved in patients with mesenteric vascular disease; (2) understand the role of angiography in the diagnosis and treatment of lower gastrointestinal bleeding; and (J) identify small bowel leiomyomas and carcinoid tumors. IN patients with celiac artery stenosis, the primary source of collateral blood flow to the organs supplied by that artery develops from the superior mesenteric artery (SNlA), primarily over the pancreatoduodenal arteries and gastroduodenal artery. The degree of celiac stenosis can be assessed by evaluating the relative filling of the hepatic and splenic arteries from the SMA. If the stenosis is 80% to 90%, the entire celiac distribution will be supplied from the SMA, and the celiac stenosis can be identified as the contrast medium passes the orifice. If less than 80%, the collateral flow from the SMA supplies the liver to varying degrees, whereas the spleen receives blood supply from the celiac artery. In patients with distal aortic occlusions, many of which also include occlusion of the inferior mesenteric artery (IMA), the SMA becomes the primary source of collateral blood flow to the pelvis and legs. The collaterals develop over the middle colic artery, left colic artery, and superior hemorrhoidal artery to the inferior hemorrhoidal branches of the internal iliac arteries. The
marginal artery of Drummond also frequently participates in this pattern of collateral flow. In patients with infradiaphragmatic IVe occlusions, the superior mesenteric and portal veins have a similar collateral function in the reverse direction.
Mesenteric Occlusive Disease Mesenteric artery occlusion may be either chronic or acute. Most chronic occlusions are caused by atherosclerosis--usually, by aortic atherosclerotic disease that impinges on the SMA or IMA orifice. Most acute occlusions are caused by emboli. Long-term gradual SMA occlusions may be identified by the collaterals that develop from the celiac axis or the IMA in a direction opposite from that described in the previous section. In patients with IMA occlusion, the SMA is the primary source of collateral blood flow to the left colon. This occurs over the middle colic and left colic arteries to the distribution of the IMA. The marginal artery of Drummond frequently participates in this collateral pattern. If both the SMA and IMA are occluded, the celiac artery and hemorrhoidal vessels may be the only collateral blood supply to the bowel. The syndrome of mesenteric ischemia probably requires that at least two major vessels be involved before the syndrome occurs because of the effectiveness of the collateral blood flow between adjacent arteries. If individual branches of the SMA or IMA are occluded, many potential collateral pathways are available over the multiple arcades that exist between adjacent mesenteric artery branches. Most emboli to the SMA lodge at branches of the mesenteric arteries, and the defect in the artery is usually readily apparent. The acuteness can be determined by the absence of collateral arteries. Although most mesenteric occlusions proceed to bowel necrosis, on occasion, adequate collateral blood flow may develop to prevent necrosis and the patient may develop a long-term occlusive pattern with collateral blood flow as described above. Nonocclusive mesenteric ischemia is an unusual cause of mesenteric occlusion. This usually occurs in elderly, hypovolemic patients and has a rather typical appearance. All of the jejunal and ileal arteries are truncated at the origins from the SMA. As the disease progresses, the arteries may develop a somewhat beaded appearance. If not detected early, this process will lead to bowel necrosis, but the process may be reversed with the infusion of vasodilatory drugs if discovered early enough. The vascular pattern of ischemic small bowel disease is hypovascularity. The SMA branches beyond the occlusion are absent. With acute mesenteric occlusions, an element of vasoconstriction is present that accentuates the hypovascularity. With the ischemic colon, on the other hand, the vasa recta may be quite hypervascular with a great deal of arteriovenous shunting. This is caused by invasion of the ischemic mucosa by the many
279