Lower GI Bleeding Flashcards
What percentage of lower GI bleed is actually from an upper GI source? Why is this important?
10%
important becaus eyou definitely don’t want to miss it - upper GI bleeds become hemodynamically unstable very rapidly
What percentage of lower GI bleeding is form a colonic source? Small bowel source?
colonix - 85%
small bowel - 5%
What are the main causes of small bowel bleeding?
- angioectasia
- ulcers
- IBD
- infecitons
- aortoenteric fistula
- diverticular hemorrhage (butt hat would usually be colon)
- Meckel diverticulum - especially in an adolescent!!
What are the main cuases of colonic bleeding?
- diverticular hemorrhage - 30 to 50%
- angiodysplasia 20-30%
- ischemia
- postpolypectomy
- neopaslm
- IBD
- infection
- radiation colitis (hx)
- anorectal disorders
Why do diverticuli form?
there are penetrating blood vessels that travel through the sera into the submucosa. this creates a natural weakness in the wall which allows the bowel layers to pop out under times of continuous high pressure (from low fiber diet)
this is why diverticuli won’t form in the rectum- the blood pattern is different
What part of the GI tract is most commonly affected by diverticuli?
sigmoid alone - 65%
sigmoid and another colonic segment - 30%
cecum - 7%
What percentage of people over 85 will have diverticulosis?
85%
What percentage of people with diverticulosis will have symptoms of either diverticulitis or hemorrhage?
20%
What are the symptoms and complications of diverticuli?
pain, diarrhea, fever and abdominal tenderness
hemorrhage is rare
complications include abscess, rupture or fistulas to adjacent organs
What imaging modality is used for diagnosis of diverticulitis?
CT (not endoscopy or barium enema)
If you have mild diverticulitis without peritoneal signs, wha tis the treamtent/
oral hydration, liquid diet, 10 days of oral antibiotics
If you have severe pain, are elderly with comorbidities or can’t take food orally, wha tis the treatment?
hospitalizaiton, IV antibiotics, NPO, and CT for further complications
What percentage of lower GI bleeding is caused by acute diverticular hemorrhage?
50%
True or flase: the hemorrhage from acute diverticuli hemorrhage is self limited in only 10% of cases.
false - in 80%
True or false: bleeding from acute diverticular hemorrhage almost always recurrs, so surgery is typically needed.
false - it only recurs in 1/3 of patients
but if you do have a recurrence, you’re very likely to have another recurrence, so then you do surgery
Describe management of diverticular hemorrhage?
- resuscitation
- reverse anticoagulation
- transfuse if necessary
- consider/exclude upper GI bleed
- observe, since most are self limited
- colonoscopy if it persists with the options of epinephrine, clips , cautery and bands for treatment
may require surgery
What is anioectasia/angiodysplasia?
when there is a tortuous, dilated submucosal capillary/vein network that lacks any small muscle (weak)
they’re spider like and can occur anywhere, but usually the right colon
How do the angioctasias present/
overt hemorrhage or anemia
What percentage of angioectasias will rebleed without endotherapy?
80%
What are the three associated “comorbidities” for angioectasia?
aortic stenosis (Heyde’s syndrome)
chronic renal failure
advanced age
What is the treatment for angiodysplasia?
colonoscopy with ablation using argon plasma, cautery or hemoglips
if that doesn’t work, may need to do a subtotal colectomy
What are the three general causes of colitis that can contrbute to lower GI bleeding?
- inflammatory (Crohns, UC and NSAIDS)
- infections (salmonella, shigella, campylobacter, E coli)
- ischemica
How does ischemic colitis present?
usually acute, severe abdominal pain followed by self-limited hematochezia (passing of bright red blood - lots of it)
may have mild to moderate focal tenderness, fever, WBC elevation and ielus
True or false: ischemic colitis almost always as complications like stricutres or perforation down the ine.
false - most are without complications and resolve completely
Wher ein the colon is ischemic colitis most likely to occur?
left splenic flexure because it only receives a limited blood supply from the IMA
the right colon is much less likely to be involved because it receives many anastomoses form the SMA
So which would be worse - left sided ischemic colitis or right sided ischemic colitis?
definitely right sided - it’s a whole different beast
What will you see on CT in ischemic colitis?
a thickened colon wall
In speaking about neoplasm….right colon neoplasia is most likely to present with ____ while left colon neoplasia is more likely to present with _____
right = anemia left = obstruction (because it's narrower)
but both can present with occult, slow bleed, or anemia, rarely hematochezia
What are the two general types of radiation proctitis?
acute radiation proctitis (with tenesmus, diarrhea, pain, rarely bleeding)
chronic radiation proctopathy (anemia, hematochezia months oryears after the radiation)
What’s the treatment for radiation proctitis/
endoscopic ablation of the areas with argon
used to use formaldehyde, SCFA enemas and steroids, but not much anymore
What is an anal fissure? WHere does it usually occur?
It’s an acute or chronic tear in the anal canal - usually on the posterior wall
How will an anal fissure present?
pain and bright blood with stool passage
in acut einstances, people can often pin point the exact onset
What are the common causes/comorbidities of anal fissures?
constipation (strainign)
diabetes
crohn’s disease
What is the treatment for an anal fissure?
stool softening and bulking with fiber
topical nitrates and calcium channel blockers to inhibit internal sphincter spasms, (which make it worse)
lateral sphincterotomy
sphincter dilation (almost never)
What is a hemorrhoid?
a dilated plexus of submucosal middle and superior hemorrhoidal veins
What are the symptoms of a hemorrhoid?
bleeding, pruritis, pain if thrombosis
What is the peak incidence for hemorrhoids?
45-60; it’s rare in those under 20
What are the risk factors for hemorrhoids?
advancing age, diarrhea, pregnancy, prolonged sitting, straining and chronic constipation
What is the treatment for hemorrhoids?
stool softening and bulkig with fiber
banding or hemmorrhoidectomy
