Lower GI Bleeding, C50 P334-337 Flashcards
What is the definition of
lower GI bleeding?
P334
Bleeding distal to the ligament of Treitz;
vast majority occurs in the colon
What are the symptoms?
P334
Hematochezia (bright red blood per
rectum [BRBPR]), with or without
abdominal pain, melena, anorexia, fatigue,
syncope, shortness of breath, shock
What are the signs?
P335
BRBPR, positive hemoccult, abdominal
tenderness, hypovolemic shock, orthostasis
What are the causes?
P335
Diverticulosis (usually right-sided in
severe hemorrhage), vascular ectasia,
colon cancer, hemorrhoids, trauma,
hereditary hemorrhagic telangiectasia,
intussusception, volvulus, ischemic colitis,
IBD (especially ulcerative colitis),
anticoagulation, rectal cancer, Meckel’s
diverticulum (with ectopic gastric
mucosa), stercoral ulcer (ulcer from hard
stool), infectious colitis, aortoenteric
fistula, chemotherapy, irradiation injury,
infarcted bowel, strangulated hernia, anal
fissure
What medicines should be
looked for causally with a
lower GI bleed?
P335
Coumadin®, aspirin, Plavix®
What are the most common
causes of massive lower GI
bleeding?
P335
- Diverticulosis
2. Vascular ectasia
What lab tests should be
performed?
P335
CBC, Chem-7, PT/PTT, type and cross
What is the initial treatment?
P335
IVFs: lactated Ringer’s; packed red blood
cells as needed, IV x 2, Foley catheter to
follow urine output, d/c aspirin, NGT
What diagnostic tests should
be performed for all lower
GI bleeds?
P335
History, physical exam, NGT aspiration
(to rule out UGI bleeding; bile or blood
must be seen; otherwise, perform EGD),
anoscopy/proctoscopic exam
What must be ruled out in
patients with lower GI
bleeding?
P335
Upper GI bleeding! Remember, NGT
aspiration is not 100% accurate (even if
you get bile without blood)
How can you have a UGI
bleed with only clear succus
back in the NGT?
P335
Duodenal bleeding ulcer can bleed distal
to the pylorus with the NGT sucking
normal nonbloody gastric secretions! If
there is any question, perform EGD
What would an algorithm
for diagnosing and treating
lower GI bleeding look like?
P336 (picture)
(see picture)
What is the diagnostic test of choice for localizing a slow to moderate lower GI bleeding source? P336
Colonoscopy
What test is performed to localize bleeding if there is too much active bleeding to see the source with a colonoscope? P337
A-gram (mesenteric angiography)
What is more sensitive for a slow, intermittent amount of blood loss: A-gram or tagged RBC study? P337
Radiolabeled RBC scan is more sensitive for blood loss at a rate of ≥ 0.5 mL/min or intermittent blood loss because it has a longer half-life (for arteriography, bleeding rate must be ≥ 1.0 mL/min)
What is the colonoscopic
treatment option for bleeding
vascular ectasia or polyp?
P337
Laser or electrocoagulation; local
epinephrine injection
What is the treatment if bleeding site is KNOWN and massive or recurrent lower GI bleeding continues? P337
Segmental resection of the bowel
What is the surgical treatment of massive lower GI bleeding WITHOUT localization? P337
Exploratory laparotomy with intraoperative
enteroscopy and total abdominal
colectomy as last resort
What percentage of cases
spontaneously stop bleeding?
P337
80%–90% stop bleeding with resuscitative measures only (at least temporarily)
What percentage of patients
require emergent surgery
for lower GI bleeding?
P337
Only ≈10%
Does melena always signify
active colonic bleeding?
P337
NO—the colon is very good at storing
material and often will store melena/
maroon stools and pass them days later
(follow patient, UO, HCT, and vital signs)
What is the therapeutic
advantage of doing a
colonoscopy?
P337
Options of injecting substance
(epinephrine) or coagulating vessels is an
advantage with C-scope to control bleeding
What is the therapeutic
advantage of doing an
A-gram?
P337
Ability to inject vasopressin and/or
embolization, with at least temporary
control of bleeding in > 85%
