Teaching Sessions Flashcards
Outline an approach to bowel obstruction
Extraluminal, mural, intraluminal
What are the two most common causes of bowel obstruction?
Adhesions and Hernias
Name 4 extramural causes of bowel obstruction (6 listed)
Adhesions Hernias Malignancy Volvulus Abscess Endometriosis
Name 3 mural causes of bowel obstruction (6 listed)
GI malignancy (large bowel, small bowel, or metastatic)
Stricture (eg due to Crohn’s or Meckel’s)
Radiation (causing stricture, usually)
Congenital malformations
Name 3 luminal causes of bowel obstruction (5 listed)
Gallstone Foreign body Bezoar Parasites Feces, meconium
What is gallstone ileus?
Obstruction due to gallstone in the small bowel.
Happens because a fistula forms between gallbladder and duodenum (or other, eg biliary tree, stomach) which releases gallstone
What are the four signs of gallstone ileus on AXR?
- Pneumobilia (air in the biliary tree, w/o prior sphincterotomy)
- bowel obstruction (complete or partial)
- … gallstone (most commonly in iliac fossa)
- tumbling obstruction (serial images: obstruction is farther along)
Dx based on first three = Rigler triad
What must you do after removing the culprit stone when doing surgery for gallstone ileus?
Run the proximal small bowel: significant portion of people have second stone
What is Meckel’s diverticulum?
Small bowel diverticulum
Formed due to defective closing of embryonic structure
What is the “rule of 2s” for Meckel’s?
- 2 inches long
- 2 feet proximal to the ileocecal valve
- 2% of the general population (M>F)
How can Meckel’s be problematic?
- hemorrhage (most common)
- obstruction (volvulus, intussiception, Littre’s)
- perforation
- infection (Meckel’s diverticulitis)
What ectopic tissue can be found in a Meckel’s? Why is it important?
Gastric! Produces acid
can contribute to hemorrhage and perforation
Damages area across the lumen from the diverticulum itself
What are the three most common causes of pancreatitis?
Gallstones
Alcohol
(Together make up approx 80% of cases; distribution depends on local pop)
Idiopathic (10%)
Name the other most common causes of pancreatitis
I GET SMASHED: Idiopathic, Gallstones, EtOH, then: Trauma Steroids Mumps Autoimmune Scorpion (or, brown recluse spider?) Hypercalcemia, high cholesterol ERCP Drugs
What is highly likely for a patient presenting with painless jaundice?
Malignant obstruction (of the bile duct)