Chapter 49: Lower Gi Bleeding

Question 1

What is the definition of lower GI bleeding?

Answer 1

Bleeding distal to the ligament of Treitz; vast majority occurs in the colon

Question 2

What are the symptoms?

Answer 2

• Hematochezia
  
  • (bright red blood per rectum [BRBPR])

with or without:

• abdominal pain
• melena
• anorexia
• fatigue
• syncope
• shortness of breath
• shock

Question 3

What are the signs?

Answer 3

• BRBPR
• positive hemoccult
• abdominal tenderness
• hypovolemic shock
• orthostasis

Question 4

What are the causes?

Answer 4

1. Diverticulosis (usually right-sided in severe hemorrhage)
2. vascular ectasia
3. colon cancer
4. hemorrhoids
5. trauma
6. hereditary hemorrhagic telangiectasia
7. intussusception
8. volvulus
9. ischemic colitis
10. IBD (especially ulcerative colitis)
11. anticoagulation
12. rectal cancer
13. Meckel’s diverticulum (with ectopic gastric
    mucosa)
14. stercoral ulcer (ulcer from hard stool)
15. infectious colitis
16. aortoenteric fistula
17. chemotherapy
18. irradiation injury
19. infarcted bowel
20. strangulated hernia
21. anal fissure

Question 5

What medicines should be looked for causally with a lower GI
bleed?

Answer 5

Coumadin®, aspirin, Plavix®

Question 6

What are the most common causes of massive lower GI bleeding?

Answer 6

1. Diverticulosis
2. Vascular ectasia

Question 7

What lab tests should be performed?

Answer 7

• CBC
• Chem-7
• PT/PTT
• type and cross

Question 8

What is the initial treatment?

Answer 8

1. IVFs:

• Lactated Ringer’s
• packed red blood cells as needed
• IV × 2

1. Foley catheter to follow urine output
2. discontinue aspirin
3. NGT

Question 9

What diagnostic tests should be performed for all lower GI bleeds?

Answer 9

• History
• physical exam
• NGT aspiration
  
  • to rule out UGI bleeding; bile or blood must be seen otherwise, perform EGD
• anoscopy/proctoscopic exam

Question 10

What must be ruled out in patients with lower GI bleeding?

Answer 10

Upper GI bleeding! Remember, NGT aspiration is not 100% accurate (even if you get bile without blood)

Question 11

How can you have a UGI bleed with only clear succus back in the
NGT?

Answer 11

Duodenal bleeding ulcer can bleed distal to the pylorus with the NGT sucking normal nonbloody gastric secretions! If there is any question, perform EGD

Question 12

What would an algorithm for diagnosing and treating lower GI
bleeding look like?

Answer 12

Question 13

What is the diagnostic test of choice for localizing a slow to
moderate lower GI bleeding source?

Answer 13

Colonoscopy

Question 14

What test is performed to localize bleeding if there is too much
active bleeding to see the source with a colonoscope?

Answer 14

A-gram (mesenteric angiography)

Question 15

What is more sensitive for a slow, intermittent amount of blood loss:
A-gram or tagged RBC study?

Answer 15

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)

Question 16

What is the treatment if bleeding site is KNOWN and massive or
recurrent lower GI bleeding continues?

Answer 16

Segmental resection of the bowel

Question 17

What is the surgical treatment of massive lower GI bleeding
WITHOUT localization?

Answer 17

Exploratory laparotomy with intraoperative enteroscopy and total abdominal colectomy as last resort

Question 18

What percentage of cases spontaneously stop bleeding?

Answer 18

80% to 90% stop bleeding with resuscitative measures only (at least temporarily)

Question 19

What percentage of patients require emergent surgery for lower GI
bleeding?

Answer 19

Only ≈10%

Question 20

Does melena always signify active colonic bleeding?

Answer 20

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)

Question 21

What is the therapeutic advantage of doing a colonoscopy?

Answer 21

Options of injecting substance (epinephrine) or coagulating vessels is an advantage with C-scope to control bleeding

Question 22

What is the therapeutic advantage of doing an A-gram?

Answer 22

Ability to inject vasopressin and/or embolization, with at least temporary control of bleeding in >85%

Question 23

45-year-old male with dark blood per rectum

Name the diagnostic modality:

Answer 23

NGT aspiration to evaluate for upper GI bleed (if blood, then EGD; if bile and no blood, then work up for lower GI bleed)

Question 24

45-year-old male with significant massive blood per rectum; NGT
reveals bile and no blood

Name the diagnostic modality:

Answer 24

Angiography to find lower GI source