LGIB, part 2

Question 1

Remarks on LGIB

Answer 1

1. Historically, LGIB is the loss of blood from the GI tract distal to the ligament of Treitz
2. However, management and outcomes differ if the bleeding originates from the small intestinge compared with the colon.
3. Nevertheless, lower GI blleding is a common problem in emergency medicine and should be considered potentially life threatening until proven otherwise
4. LGIB occurs more often than UGIB.

Question 2

The most common source for all causes of blood detected in the lower GI system

Answer 2

UGIB

Question 3

Among patients with an established lower GI source of bleeding, the most common cause is

Answer 3

Diverticular disease
followed by
colitis
hemorrhoids
adenomatous polyps/malignancies

Question 4

Remarks on diverticular bleeding

Answer 4

Diverticular bleeding is usually painless and results from erosion into the penetrating arery of the diverticulum.

Diverticular bleeding may be massive, but up to 90% of episodes will resolve spontaneously.

Although most dierticular are located on the left colon, right-sided diverticular are thought to be more likely to bleed

Question 5

Most common cause of intestinal ischemia

Answer 5

Ischemic colitis
*usually transient**

Question 6

Remarks on Meckel’s diverticulum

Answer 6

1. Most commonly found in the terminal ileum
2. More than half of lesions contain ectopic gastric tissue, which can secrete gastric enzymes, eroding the mucosal wall and causing bleeding
3. It is rare but important condition, especially in the younger population.

Question 7

Most common cause of anorectal bleeding

Answer 7

Hemorrhoids
Massive hemorrhage is unsuual
Bleeding is usually associated with bowel movements and is usually painless

Question 8

Predictive of severe bleeding in LGIB

Answer 8

nontender abdomen
In patients with LGIB, a lack of abdominal tenderness suggests bleeding from disorders involving the vascularture, such as diverticulosis or angiodysplasia

Question 9

predictive of diverticular hemorrhage

Answer 9

aspirin or NSAID use

Question 10

The most important laboratory tests in LGIB

Answer 10

CBC
Coagulation studies
Blood typing
Crossmatching

Question 11

The initial diagnostic of choice for LGIB

Answer 11

Angiography, scintigraphy, or endoscopy
- depends on resource ability and consultant preference

Question 12

Remarks on angiography

Answer 12

Angiographic diagnosis and therapy require a relatively brisk bleeding rate (at least 0.5 mL/min).

Serious complications can also occur with angiography in up to 10% of cases

Question 13

Remarks on scintigraphy

Answer 13

1. Technetium-labeled RBCs scans can localize the site of bleeding in obscure hemorrhage and can help determine if angiography or surgery is the optimal approach
2. Scintigraphy appears more sensitive than angiography and can localize the site of bleeding at as low a rate as 0.1 mL/min
3. It also has potential value over angiography if bleeding occurs intermittently but requires a minimum of 3 mL of blood to pool

Question 14

Remarks on CT in LGIB

Answer 14

It can be a useful tool, especially in unstable LGIBs, prior to treatment with conventional angiography

Can detect bleeding at as low as 0.4 mL/min

Question 15

Blood transfusion in LGIB

Answer 15

Blood transfusion should be based on the clinical findings of significant blood loss or continued bleeding rather than on initial hematocrit values as it takes several hours for the hematocrit to decrease.

Question 16

Timing of colonoscopy in LGIB

Answer 16

Some studies suggest that urgent colonoscopy is both safe and accurate within 12 to 24 hours of admission, but others report that delayed colonoscopy is appropriate in stable patients.

Question 17

Disposition in LGIB

Answer 17

Currently no reliable scoring system exists to risk stratify which patients with lower GI bleeding may be discharged home safely.

However, those with an obvious cause of mild bleeding (such as mild bleeding from hemorrhoids or anal fissures), or who have no bright red blood or maroon or melanotic stool on rectal examination and ahre hemodynamically stable and without major comorbidities, may be candidates for outpatient treatment.