Lecture 3: GI Bleeding Flashcards
Upper GI bleeding
bleeding from a source proximal to the ligament of Treitz (duodenal suspensory muscle)
BUN/creatinine of >20
UGI source
blood clots
LGI source
What causes bleeding from the small bowel?
1) lesions between ligament of Treitz and ileocecal valve-5%
2) Angioectasias (arteriovenous malformations or angiodysplasia)-older patients common
3) IBD (erosions or ulcers)
4) NSAIDs enteropathy (erosions, ulcers)
5) tumors
6) Meckel’s diverticulum-kids
Meckel’s Diverticulum
1) most common anomaly of GI tract
- most peoples asymptomatic
- distal ileum
2) results from failure of omphalomesentric duct to undergo involution during development (yolk sac does not shrink)
3) true diverticulum; contains heterotypic mucosa (in weird location) most commonly gastric mucosa
What are complications of Meckel’s Diverticulum?
1) bleeding occurs due to ulceration within the diverticulum or from adjacent mucosa (due to ectopic acid production)-most common in kids
2) can cause obstruction (intussusception, volvulus) or diverticulitis (GI inflammation)
3) treat: resection (surgically remove)
What causes lower GI massive bleeding?
1) diverticular bleed (pouches in the wall of the colon bleed)
2) ischemia
3) AVMs
What is LESS likely to cause lower GI massive hemorrhage?
1) IBD
2) colon cancer
3) hemorrhoids
What is OCCULT GI bleeding?
1) hidden/secret
2) bleeding NOT visible to patient/physician
3) manifested by iron deficiency or positive fecal occult blood test
4) typical of early colon cancers
What is OBSCURE GI bleeding?
1) overt or occult bleeding that persists or recurs after initial negative endoscopic/colonoscopic evaluation
2) usual approach is to confirm negative endoscopies, then focus on potential small bowel source
- video capsule endoscopy, deep enteroscopy, angiography, CT enterography vs empiric iron replacement
Iron Deficiency in Adults
1) assumed due to occult (sneaky) blood loss until otherwise proven
2) should always be evaluated not just treated with supplemental iron
3) lab features include
- decreased saturation of transferrin with iron (reflects both decrease in serum iron and compensatory increase in transferrin/TIBC)
- decrease in ferritin (indicates depletion of stored iron)
- with or without microcytic anemia (low MCV)
How do you treat GI bleeding?
1) acid suppression (PPIs), IV ocretotide for acute vatical bleeding
2) endoscopic hemostasis: placement of hemoclips, cauterization, treatment of superficial mucosal lesions with laser or argon plasma coagulator, injection of epinephrine, ligation or gluing of varies
3) Insulin resistance: angiography with embolization of bleeding vessel, TIPS for refractory vatical bleeding
4) surgery: reserved for failure of nonsurgical treatments for ulcer bleeding
When should you do endoscopy?
1) urgent upper endoscopy in UGI bleeding: lowers mortality, hospital stay, transfusion needs
2) data for urgent colonoscopy in LGI bleeding is less compelling
- bowel prep
- difficult to find bleeding site
3) resuscitation and stabilization should be priorities prior to endoscopy/colonoscopy
4) if massive bleed and cannot stabilize forego endoscopy
When do you use angiography?
1) identify and treat (embolize) sites of bleeding
2) procedure of choice in hemodynamically unstable patient
3) ID bleeding site requires active bleeding
4) does NOT need bowel prep
5) Risks: contrast allergies. contrast induced AKI, bleeding from puncture site, bowel ischemia
When do you use tagged RBC (bleeding) scan?
1) autologous RBCs labelled with technetium-99m
2) tagged RBCs reinfused with imaging performed
3) can be re-imaged every few hrs if needed
4) can be helpful for evaluating intermittent bleeding, esp if bleeding persists/recurs after negative endoscopy
5) requires active bleeding but more sensitive than angiography
6) location of actual bleeding site is tricky
