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37 Cards in this Set
- Front
- Back
What are the 3 vascular disorders of the colon?
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1. Ischemic bowel disease
2. Angiodysplasia 3. Hemorrhoids |
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What are 3 predisposing factors to ischemic bowel disease?
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-Old age
-CV disease -Pre-existent abdominal disease |
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What is the death rate in bowel infarctions?
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50-70%
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What are 4 clinical symptoms of a complete bowel infarction?
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-Sudden severe pain
-Bloody diarrhea -Shock -Rigid abdominal wall with loss of bowel sounds |
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What symptom will be seen in chronic ischemic colitis?
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Intermittent bloody diarrhea
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With what kind of an infarction is there a highest mortality rate?
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Transmural infarction
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What causes a TRANSMURAL infarct usually?
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Mechanical compromise of major mesenteric blood vessels (SMA/IMA)
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What most commonly causes a MURAL infarct?
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Acute or Chronic hypoperfusion
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What is the difference between a Transmural, Mural, and Mucosal infarction?
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Transmural: involves all visceral layers of the intestinal wall
Mural: only mucosa/submucosa Mucosal: only extends down to the muscularis mucosa |
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What part of the intestinal wall is the most susceptible to ischemia?
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The tips of villi
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What are the 5 categories of predisposing conditions for ischemic bowel disease?
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1. Arterial thrombosis
2. Arterial embolism 3. Venous thrombosis 4. Non-occlusive ischemia 5. Miscellaneous |
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What are 3 non-occlusive causes of bowel ischemia?
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-Cardiac failure
-Shock -Vasoconstrictive drugs |
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What are 4 miscellaneous causes of bowel ischemia?
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-Radiation therapy
-Amyloidosis -Stricture -Herniation |
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What are the 2 phases of ischemic injury? Which one causes more damage in IBD?
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1. Initial hypoxic injury
2. Secondary reperfusion injury - causes the more damage |
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What occurs in reperfusion that damages the intestinal wall?
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-Generation of ROIs
-Inflammatory mediators -PMN infiltration |
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What are the 2 highest risk areas for large bowel ischemia?
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-Splenic flexure
-Rectum |
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Why is bowel infarction so deadly?
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Because there is a small window of time between symptom onset and perforation
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What patients tend to get bowel infarcts more?
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Older patients with cardiac and vascular diseases
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What are severe abdominal pain and tenderness signs of?
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Transmural infarct
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Why is diagnosis of intestinal gangrene resulting from infarction often delayed or missed?
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Because the symptoms like pain and board-like rigidity are often seen in other acute intestinal conditions.
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What can be indicated by a confusing array of nonspecific abdominal complaints plus intermittent bloody diarrhea?
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Nonocclusive enteric ischemia
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What does chronic ischemic colitis often mimic?
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IBD
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What does it mean to say that both acute and chronic ischemia are segmental diseases?
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Though the splenic flexure and rectum are most susceptible, patches and segments of the entire colon can be ischemic.
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What do mucosal/mural infactions often mimic by the luminal epithelial sloughing and necrosis that occur?
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Pseudomembranous colitis
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How does the intestinal serosa appear on gross examination in
-Transmural infarction -Mucosal/submucosal infarct |
Transmural: congested, purple-red
Mucosal: normal |
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What causes Chronic ischemia of the colon? What does it mimic?
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Chronic vascular insufficiency
-Mimics acute enterocolitis and IBD |
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What is tortuous dilations of submucosal and mucosal vessels in the cecum and right colon describe?
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Angiodysplasia
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What is often the clinical manifestation of Angiodysplasia?
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Acute and massive GI bleeding
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What is a diverticulum?
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A blind pouch lined with mucosa that communicates with the gut lumen
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What are Congenital and True diverticula?
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Ones that contain all 3 layers of the bowel wall
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What is the prototype congenital diverticulum? Where are they commonly seen?
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Meckel diverticulum - often in the ascending colon
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What/where are Acquired diverticula most often?
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False - lack muscularis propria
-Most common in left sigmoid colon |
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What does Diverticular disease infer?
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Acquired outpouchings of just the mucosa and submucosa (false diverticula)
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What is the usual age and frequency of diverticulosis?
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-Adults >60
-50% prevalence |
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Are diverticula usually single or multiple?
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Multiple
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What is Diverticulitis?
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When diverticula lead to obstruction or perforation and inflammation
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What are the 2 most important factors in the development of diverticula?
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1. Focal weakness in the colon wall
2. Increased intraluminal pressure |