Large Bowel Disorders Flashcards
What is the definition of a Diverticula?
small mucosal herniations protruding through intestinal and smooth muscle layer along natural openings of the vasa recta of the colon
What is the most common area for a diverticula and why?
Sigmoid colon = highest intraluminal pressure
What is the definition of Diverticulosis?
uninflamed diverticula associated with low fiber diet, constipation, and obesity
What is the most common cause of acute lower GI bleeding?
Diverticulosis!
What is the definition of Diverticulitis?
inflamed diverticula 2ry to obstruction/infection (fecaliths) leading to distention
What are the clinical manifestations of diverticulitis?
- fever
- LLQ pain
- N/V
- diarrhea/constipation
- flatulence
What is the diagnostic test of choice for diverticulitis?
CT scan
Ba enema not done in acute phase!!
What is the management of diverticulitis?
clear liquid diet
broad spectrum abx = cipro (or Bactrim) + Metronidazole
What is the management of diverticulosis?
high fiber diet, fiber supplements
What is the definition of a volvulus?
twisting of any part of bowel in itself
Where does a volvulus most commonly happen?
sigmoid colon or cecum
What are the clinical manifestations of a volvulus?
obstructive s/sxs —> abd. pain, distention, N/V, fever, tachycardia
What is the management of a volvulus?
Endoscopic decompression initially!
Surgical correction is 2nd line
What is the most common cause of obstruction of the appendix?
Fecalith (hardening of feces)
What is the one clinical feature that can rule out appendicitis?
if the patient is hungry!!
What is Rovsing sign?
RLQ pain with LLQ palpation
What is obturator sign?
RLQ pain with internal and external hip rotation with bent knee
What is Psoas sign?
RLQ pain with right hip flexion/extension (SLR)
How is appendicitis diagnosed?
CT scan
US
leukocytosis
What is the hallmark of irritable bowel syndrome?
Abdominal pain associated with altered defecation/bowel habits (diarrhea, constipation, or alteration between the 2)
What is the clinical definition of IBS?
chronic, functional idiopathic disorder with NO organic cause
Name some “alarming symptoms” of IBS?
Evidence of GI bleeding
Anorexia or weight loss
Nocturnal symptoms
Onset > 45 years
Persistent diarrhea causing dehydration OR
Severe constipation causing fecal impaction
What are the possible pathophysiology of IBS?
- Abnormal motility –> chemical imbalance in intestine causing abnormal movements and spasm
- Visceral hypersensitivity –> lower pain thresholds to intestinal distention
- Psychosocial interactions
What specific chemicals can be imbalanced in the intestine to cause IBS?
Serotonin and Acetylcholine
What is the Rome II Diagnostic Criteria for IBS?
Abdominal pain or discomfort with 2 of 3 features for at least 12 weeks during preceding 12 months
- relief with defecation**
- onset associated with change in stool frequency
- onset associated with change in stool formation
What are the management options for IBS?
Lifestyle changes –> smoking cessation, eat low fat/unprocessed foods, sleep, exercise
Anticholinergics (Dicyclomine) Antidiarrheal (Loperamide) Prokinetics Bulk-forming laxatives Saline or osmotic laxatives
What is acute mesenteric ischemia?
sudden decrease of mesenterial blood supply to the bowel
GI EMERGENCY!!!
Where is inadequate perfusion most common in acute mesenteric ischemia and why?
at the splenic flexure b/c less collateral blood perfusion
What are the most common etiologies for acute mesenteric ischemia?
- embolus (ex. pts with Afib)
- thrombus (esp in pt with prior known atherosclerosis)
- Non-occlusive causes (less common) –> shock, cocaine
What are the clinical manifestations of acute mesenteric ischemia?
SEVERE abdominal pain out of proportion to physical findings
What is the diagnostic test of choice for acute mesenteric ischemia?
Angiogram!
What is the management for acute mesenteric ischemia?
Revascularization! (angioplasty with stenting or bypass)
Surgical resection if bowel not salvageable
What is chronic mesenteric ischemia?
mesenteric atherosclerosis of the GI tract leading to inadequate perfusion in post-prandial states (esp. at splenic flexure)
What are the clinical manifestations of chronic mesenteric ischemia?
chronic dull abdominal pain worse after meals "intestinal angina" Weight loss (anorexia)
What is the diagnostic test of choice for chronic mesenteric ischemia and what will it show?
Colonoscopy –> mucosal atrophy with loss of villi
What is the management for chronic mesenteric ischemia?
bowel rest
revascularization (angioplasty with stenting or bypass)
What is toxic megacolon?
non-obstructive, severe colon dilation > 6cm + signs of systemic toxicity
What are the most common etiologies of toxic megacolon?
UC, Crohn's pseudomembranous colitis infectious XRT ischemic Hirschsprung
What are the clinical manifestations of toxic megacolon?
Abdominal pain diarrhea N/V rectal bleeding or tenesmus fever, tachycardia, hypotension
What is Hirschsprung?
a congenital aganglionic colon (neurogenic bowel obstruction)
What is the diagnostic test of choice for toxic megacolon and what will it show?
Abdominal X-ray —> large dilated colon > 6cm
What is the management of toxic megacolon?
bowel decompression (NG tube)
bowel rest
broad spectrum abxs
Colostomy if refractory
What is the medical definition of tenesmus?
continual or recurrent inclination to evacuate the bowels
What are the clinical manifestations of ischemic colitis?
LLQ pain with tenderness and bloody diarrhea
Due to sloughing off of the colon
What is the diagnostic test of choice for ischemic colitis and what will it show?
Colonoscopy —> segmental ischemic changes in areas of low perfusion (ex. splenic flexure)
