Lower Gastrointestinal Bleeding

Aka: Lower Gastrointestinal Bleeding, Lower GI Bleed

1. See Also
   1. Gastrointestinal Bleeding
   2. Upper Gastrointestinal Bleeding
   3. Diverticular Bleeding
2. Causes: Adults with Acute Massive Rectal Bleeding
   1. Diverticular Bleeding (10-20%)
      1. Painless bleeding
      2. Increased risk with NSAIDs or Aspirin
      3. Bleeding spontaneously ceases in 75%, recurs in 38%
      4. Recurrence is 9% at one year and 25% at 4 years
   2. Angiodysplasia (3-12%)
      1. Recurrent painless bleeding
   3. Colon Cancer (2-26%)
      1. Slow chronic blood loss with change in bowel habits
   4. Inflammatory Bowel Disease (10%)
      1. Blood Diarrhea with recurrent Abdominal Pain and weight loss
   5. Ischemic Colitis
      1. Self-limited bloody Diarrhea, followed by acute lower Abdominal Pain
      2. Seen in vascular disease patients
      3. May be foretold by prior hypotensive event
   6. Rectal ulcer (hard stool induced Pressure Ulcers)
   7. Acute infectious colitis
   8. Pseudomembranous colitis (or other Infectious Diarrhea or dysentary)
      1. Bloody Diarrhea with fever and risk factors (recent antibiotics, suspect oral intakes)
   9. Radiation Colitis
      1. May be delayed 3 years after Radiation Therapy
   10. Post-polypectomy bleeding
       1. Associated with restarting NSAID or Aspirin too soon
       2. Self-limited bleeding, usually follows polypectomy or other bowel procedure within 30 days
   11. Aortoenteric fistula (Aortic graft-enteric fistula)
       1. Occurs in those with aortic surgery history
       2. Requires immediate emergency management
   12. Internal Hemorrhoid (<10%)
   13. Consider Upper Gastrointestinal Bleeding source
3. Causes: Adults with chronic intermittent GI Bleeding
   1. Hemorrhoids (Up to 59%)
   2. Colorectal polyps (38 to 52%)
   3. Diverticulosis (34 to 51%)
   4. Colorectal Cancer (up to 8%)
   5. Ulcerative Colitis
   6. Arteriovenous malformations
   7. Colonic stricture
4. Causes: Adults - most commonly missed lower GI sources
   1. Arteriovenous malformations
   2. Neoplasms in colon
5. Causes: Children
   1. Anal Fissure
   2. Infectious colitis
   3. Inflammatory Bowel Disease
   4. Polyps
   5. Intussusception
   6. Meckel's Diverticulum
6. Signs
   1. Hematochezia (bright red blood in stool)
      1. Upper Gastrointestinal Bleeding source in 5-11% of patients
   2. Nasogastric aspirate clear except for bile
      1. Positive in Upper Gastrointestinal Bleeding
   3. Normal Renal Function tests (BUN to Creatinine ratio normal)
      1. Contrast with Upper Gastrointestinal Bleeding where BUN to Creatinine ratio is increased >33
   4. Normal Bowel Sounds
   5. Hemodynamic status more stable than in Upper GI Bleed
      1. Orthostasis seen in one third of patients
7. Labs
   1. Serum electrolytes
      1. BUN to Creatinine ratio >33 suggests Upper Gastrointestinal Bleeding source
   2. Complete Blood Count
      1. Hemoglobin or Hematocrit decreased in 50% of patients
         1. Usually less depressed than in Upper Gastrointestinal Bleeding
   3. Coaulation Studies
      1. Partial Thromboplastin Time (PTT)
      2. Prothrombin Time (PT/INR)
   4. Preparation for Blood Transfusion
      1. Consent for Blood Products
      2. Type and Crossmatch for Packed Red Blood Cells (pRBC)
   5. Assessment of comorbidity and secondary complications
      1. Electrocardiogram (EKG)
      2. Troponin
8. Management: Acute Gastrointestinal Bleeding
   1. Precaution
      1. Brisk persistent bleeding occurs in up to 19% of cases
   2. Initial Stabilization
      1. ABC Management
      2. Oxygen supplementation
      3. Obtain two large bore peripheral IVs
      4. Telemetry monitoring with Heart Rate, Oxygen Saturation and Blood Pressure monitoring (also obtain orthostatic BP and Pulse if able)
      5. Obtain acute labs as above
      6. May stabilize with crystalloid (e.g. normal saline) as needed for hemodynamic instability while Blood Products pending
         1. However, blood is far preferred as soon as it is available
         2. Avoid excessive crystalloid prior to transfusion
      7. Transfuse Packed Red Blood Cells for severe Anemia, symptomatic Anemia or continued heavy bleeding
      8. Consider Fresh Frozen Plasma (ffp) and platelets as indicated for coagulopathy
   3. Avoid tests without adequate yield in acute bleeding
      1. Avoid Flexible Sigmoidoscopy
      2. Avoid Barium Enema
   4. Consider Upper Gastrointestinal Bleeding source
      1. Upper GI Bleed with Hematochezia is always unstable
      2. BUN to Creatinine ratio increased in Upper Gastrointestinal Bleeding
      3. Check Nasogastric aspirate
         1. Will show bile without blood in lower GI source
         2. Duodenal source of Upper GI Bleed may be missed
   5. Bleeding ceases spontaneously (occurs in 50% of cases)
      1. See Colonoscopy in GI Bleeding
      2. Evaluation may proceed outpatient in stable patient
      3. Colonoscopy negative: Consider Upper GI Bleed
   6. Brisk GI Bleeding obscures source on Colonoscopy
      1. See Angiography in GI Bleeding (preferred)
         1. Test of choice in massive Lower GI Bleeding
         2. May direct exploratory laparotomy
         3. Consider Arteriography with embolization or vasopressin
      2. See Radionuclide Red Cell Scan (less accurate)
         1. More useful in slower bleeding (<0.4 ml/minute)
         2. Immediate blush identifies high risk bleeding
            1. Ng (1997) Dis Colon Rectum 40:471-7
   7. Slow continuous or recurrent bleeding
      1. See Colonoscopy in GI Bleeding
      2. No source on Colonoscopy
         1. Radionuclide Red Cell Scan: Positive
            1. See Angiography in GI Bleeding
            2. Consider repeat Colonoscopy in GI Bleeding
               1. Guided by red cell scan results
            3. Consider exploratory laparotomy
               1. See below for indications
         2. Radionuclide Red Cell Scan: Negative
            1. Consider Upper Endoscopy
               1. Evaluate for Hematochezia due to Upper GI Bleed
               2. These cases are always hemodynamically unstable
            2. Consider Small Intestinal Bleeding
   8. Exploratory laparotomy
      1. Adjunctive intraoperative measures
         1. Intraoperative Colonoscopy
         2. Intraoperative angiography
         3. Subtotal colectomy is a a procedure of last resort
            1. Indicated only in uncontrolled massive hemorrhage where no alternative management exists
            2. High morbidity and mortality associated with emergent subtotal colectomy
      2. Indications
         1. Transfusion >4 units in 24 hours
         2. Transfusion >10 units total
         3. Recurrent bleeding episodes
         4. Comorbid conditions significantly affected
9. Management: Asymptomatic mild rectal bleeding (clinic)
   1. Age over 35 years: Colonoscopy
   2. Age 25 to 35 years: Diagnostics based on risk factors
   3. Age under 25 years: Anoscopy, Flexible Sigmoidoscopy
   4. Lewis (2002) Ann Intern Med 136:99-110
10. Prognosis
    1. Overall mortality <5%
    2. Mortality may approach 20% if admitted for comorbidity
11. References
    1. Demarkles (1993) Med Clin North Am 77(5):1085-100
    2. Fallah (2000) Med Clin North Am 84(5):1183-208
    3. Manten (1995) Postgrad Med 97(4):154-7
    4. Peter (1999) Emerg Med Clin North Am 17(1):239-61
    5. Zuckerman (2000) Gastroenterology 118:201-21