Colonoscopy in GI Bleeding

1. Indications
   1. Acute Lower Gastrointestinal Bleeding
2. Protocol: Timing (Hospitalized patients)
   1. Colonoscopy within 12-48 hours
      1. Allows for adequate Bowel Preparation
      2. Allows for adequate Resuscitation
3. Preparation
   1. Adequate Bowel Preparation is key to diagnosis
   2. Rapid Bowel Preparation in urgent Colonoscopy (colonic lavage with purge preparation)
      1. Uses Polyethylene glycol (PEG 3350, Golytely, Nulytely)
      2. Polyethylene glycol at 1 liter every 30-45 minutes for at least 2 hours until clear effluent OR
      3. Polyethylene glycol 4 to 6 Liters over 3-4 hours until output without stool or blood
4. Diagnosis: Colonoscopy
   1. Pitfalls
      1. Definite bleeding source in suspected Diverticular Bleeding is only identified in 10-20% of cases
         1. However overall identifies 69-80% of Lower Gastrointestinal Bleeding causes
      2. High False Positive Rate for wrong site of bleeding
      3. Sites commonly misdiagnosed as bleeding source
         1. Diverticular Bleeding
         2. Angiodysplasia
   2. Criteria for definitive diagnosis of bleeding source
      1. Active bleeding
      2. Nonbleeding visible vessel or pigmented protuberance
      3. Clot adherent to bleeding source
      4. Fresh blood in a short colonic segment
      5. Diverticular ulceration with fresh blood nearby
5. Signs: Colonoscopy findings on evaluation of Lower Gastrointestinal Bleeding
   1. Mucosal changes
   2. Infectious Colitis
   3. Ischemic Colitis
   4. Diverticular Bleeding source
6. Management: Modalities for control of bleeding sites
   1. Thermal contact probe
   2. Nd-YAG Laser
   3. Dilute epinephine injection with electrocautery
   4. Band ligation or metallic clip placement
7. References
   1. (1998) Gastrointest Endosc 48:685-88 [PubMed]
   2. Davila (2005) Gastrointest Endosc 62(5): 656-60 [PubMed]
   3. Fallah (2000) Med Clin North Am 84(5):1183-208 [PubMed]
   4. Jensen (2000) N Engl J Med 342(2): 78-82 [PubMed]
   5. Wilkins (2009) Am Fam Physician 80(9): 977-83 [PubMed]