CIS GI Case 2

Question 1

What is in the differential for hematochezia: hemorrhoids, anal fissures, diverticulum bleed, IBD, infectious colitis, ischemic colitis

Answer 1

Hemorrhoids: painless bleeding is usually associated with bowel movement, coats stool at end of defecation. Blood may also drip into toilet or stain toilet paper

Anal fissure: diagnosed from history, tearing pain with passage of bowel movements, small amount on toilet paper or on surface of stool

Diverticula bleed: painless profuse bleeding

IBD: ulcerative colitis&raquo_space; Crohn disease

Infectious colitis: similar clinical presentation and endoscopic appearance to UC. Excluded with stool and tissue cultures, stool studies, and biopsies of colon (EHEC)

Ischemic colitis: abdominal pain followed by profuse bleeding

Question 2

What is in the differential for hematochezia: AV malformation, rapid upper GIB, polyps, proctitis, rectal ulcers, colorectal cancer, radiation colitis

Answer 2

AV malformation
Rapid upper GIB
Colorectal cancer

Polyps: asymptomatic and are most often detected by colon cancer screening tests, occult bleeding

Proctitis: insidiously with intermittent rectal bleeding, passage of mucus, and mild diarrhea associated with <4 small loose stools per day (mild UC)

Rectal ulcers: can present with bleeding, passage of mucus, straining during delectation, and sense of incomplete evacuation

Radiation colitis: seen weeks-years after abdominal or pelvic irradiation

Question 3

What are important history points to ask GIB pt?

Answer 3

Prior episodes of GI bleeding
Pt’s past medical history (IBD, cancer: change in BMs, CVD, diverticulosis)
Medication use: particularly agents that are associated with bleeding or that may impair coagulation, such as NSAIs, anticoagulants, and antiplatelet agents

Question 4

What are important physical points to perform on GIB pt?

Answer 4

Assessment of hemodynamic stability as well as examination of pt’s stool to confirm pt of hematochezia or melena

Question 5

What are signs of hypovolemia?

Answer 5

Mild to moderate hypovolemia: resting tachycardia

Blood volume loss of at least 15%: 
Orthostatic hypotension (decrease in SBP of more than 20 mm Hg and/or increase in heart rate of 20 beats/min when moving from recumbency to standing)

Blood volume loss of at least 40%
Supine hypotension

Question 6

How is smoking related to ulcerative colitis?

Answer 6

Stopping smoking is risk factor for developing UC

Question 7

what is the BUN:Cr ratio in upper GIB?

Answer 7

30:1

Question 8

What is the AST:ALT ratio in an alcoholic?

Answer 8

2:1

Question 9

what is the anatomical division of upper GIB vs lower GIB?

Answer 9

Ligament of Treitz

Question 10

what happens when beta blocker is abruptly stopped?

Answer 10

Rebound tachycardia

Question 11

What skin finding is found in many inflammatory conditions?

Answer 11

Erythema nodosum
Red nodular areas on shins

Seen in pt with IBD

Question 12

Describe advantages/disadvantages of radionuclide imaging

Answer 12

Advantages:
Noninvasive
Sensitive to low rates of bleeding
Can be repeated for intermittent bleeding

Disadvantages:
Has to be performed during active bleeding
Poor localization of bleeding site
Not therapeutic
Not widely available

Question 13

Describe advantages/disadvantages of CT angiography

Answer 13

Advantages:
Noninvasive
Accurately localizes bleeding source
Provides anatomic detail
Widely available

Disadvantages:
Has to be performed during active bleeding
Not therapeutic
Radiation and IV contrast exposure

Question 14

Describe advantages/disadvantages of angiography

Answer 14

Advantages:
Accurately localizes bleeding source
Therapy possible with super-selective embolization
Does not require bowel preparation

Disadvantages:
has to be performed during active bleeding
Potential for serious complications

Question 15

Describe advantages/disadvantages of colonoscopy

Answer 15

Advantages:
Precise diagnosis and localization regardless of active bleeding or type of lesion
Endoscopic therapy possible

Disadvantages:
Need colon preparation for optimal visualization
Risk of sedation in acutely bleeding pt
Definitive bleeding source (stigmata) infrequently identified

Question 16

What diagnostics should be considered when there is concern for upper GI bleeding source?

Answer 16

High index of suspicion: Upper endoscopy (EGD)
Must stabilize pt with IVF and blood

Moderate suspicion: nasogastric tube with lavage
Positive UGIB = coffee-ground material or bright red blood
-Can be falsely negative if bleeding has ceased or is beyond closed pylorus (duodenal bleed)
-Negative: bilious fluid indicates open pylorus, no active bleeding proximal to ligament of Treitz
-Indeterminate: no blood or bile. Do upper endoscopy

Question 17

What is the initial management of acute lower GI bleed?

Answer 17

Supportive: IV access, appropriate setting (outpatient/inpatient/ICU), O2, IVF, blood products, assessment and management of coagulopathies

In pts with ongoing bleeding or high-risk clinical features:

• colonoscopy should be performed within 24 hours of presentation after adequate colon preparation to potentially improve diagnostic and therapeutic yield
• Perform colonoscopy as soon as pt has been resuscitated and adequate bowel preparation (typically 4-6 L of polyethylene glycol) has been given
• -nasogastric tub may help with getting prep down

Question 18

What are considerations for blood transfusion with packed RBCs?

Answer 18

First type and screen if hemoglobin is stable and no acute bleed

Type and cross (and hold vs transfuse)

• Young pts without comorbid illness may not require transfusion until hemoglobin <7g/dL
• Older pts and those who have more severe comorbid illnesses such as CAD require >9 g/dL
• *Pts with active bleeding and hypovolemia may require a blood transfusion despite apparently normal hemoglobin

Obtain iron studies before transfusion because afterwards, they are inaccurate

Question 19

What are some potential complications or risks in pts with ulcerative colitis?

Answer 19

Toxic megacolon (emergency -> surgery for colectomy)
Primary sclerosing cholangitis (M>F)
Ankylosing spondylitis
Pyoderma gangrenosum

Question 20

What are some potential complications or risks in pts with Crohn disease?

Answer 20

Fistulas/strictures
Fissures
Pigmented gallstone formation
Malabsorption

Question 21

What are some potential complications or risks in pts with both ulcerative colitis and Crohn disease?

Answer 21

Colon cancer

*DVT

Question 22

How fast can potassium chloride (KCl) be given through peripheral IV?

Answer 22

10 mEq/hr (otherwise irritating to vein)

Question 23

How many g/dL would the hemoglobin raise from 1 unit of packed red blood cells (PRBCs)?

Answer 23

Giving 1 unit of PRBCs should increase Hgb by 1g/dL

Question 24

During acute IBD flare, what is the primary treatment?

Answer 24

Corticosteroids (IV or PO)

Question 25

What is the gold standard for colorectal cancer screening?

Answer 25

Colonoscopy
Every 10 years
Requires less frequent screening
Screening and diagnostic follow-up of positive findings can be performed during same exam

Question 26

Describe colorectal cancer screening strategies: stool-based tests

Answer 26

Guaiac-based fecal occult blood test (aFOBT)
Every year
No prep. Can be done at home

Fecal immunochemical test (FIT)
Every year
More accurate than gFOBT
No prep. Can be done at home with one sample

FIT-DNA
Every year or 3 years
More false-positives than FIT but better sensitivity

Question 27

Describe colorectal cancer screening strategies:CT colonography, flexible sigmoidoscopy, flexible sigmoidoscopy with FIT

Answer 27

CT colongraphy
Every 5 years

Flexible sigmoidoscopy
Every 5 years
Less benefit than with FIT. Declined in US

Flexible sigmoidoscopy with FIT
Scope every 10 years, FIT every year
Declined in US
Option for pts who want endoscopic screening but limit exposure to colonoscopy