Investigation of Lower Gastrointestinal Bleeding

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					 Investigation of Lower
Gastrointestinal Bleeding

           Dean Trotter
Austin Health (Maroondah Hospital)
                 Lower GIT bleeding
• Definition: abnormal loss of blood from the GIT distal to the
  suspensory ligament of the duodenum (ligament of Treitz)1

• Occult
   = bleeding that is not apparent to the patient
   – positive FOB test
   – iron deficiency anaemia
• Overt
   – minor
   – massive

• Actual incidence unknown (? ~0.5-1% all hospital admissions)

• 85% of all lower GIT haemorrhage stops spontaneously
                                Aetiology
                                                          % incidence2
•   Diverticular disease                                       40
•   Inflammatory bowel disease                                 21
     – Crohn’s / UC
     – Infective colitis
     – Ischaemic colitis
•   Neoplasia                                                   14
     – Benign / Malignant
•   Coagulopathy                                                12
•   Benign anorectal disease                                    11
     – Haemorrhoids / Anal fissure / Fistula-in-ano
•   Arteriovenous malformations                                 02
•   Small intestinal sources
     – AVM
     – Diverticula
         • Meckel’s
     – Neoplastic

•   10-15% of all rectal bleeding arises from sources proximal to lig of Treitz
                            Aetilogy
• Diverticular disease
   – Prevalence (Western society) 37-45%
   – Risk of bleeding around 17%3 (4-48%)
   – 80% of diverticular bleeding ceases spontaneously4
   – risk of re-bleeding     - 25% (if 1 prior bleed)
                             - 50% (if >1 prior bleed)5
   – 5% ultimately require emergency operation
   – Pathophysiology
       •   Diverticula form where vasa recta penetrate the muscularis
       •   Therefore vessels course the dome of the diverticulum
       •   As diverticulum enlarges, vessels rupture
       •   Diverticular h’age arises from the R) colon in 70-90% pts
             (~5% of patients with diverticular dis have R) colon diverticulae)
Diverticular bleeding
                   Aetiology
• Inflammatory bowel disease
  – Crohn’s > U.C. (deep transmural ulceration)
  – Up to 6% experience severe GIT bleeding6
     • 50% stop spontaneously
        – Of these, 35% re-bleed
     • Colectomy recommended in this patient group
AVM

 •   Incidence of up to 30% of
     population over 50
 •   Chronic intermittent colonic
     wall contraction causes varicose
     submucosal veins
 •   Most common in caecum
     (greatest wall tension)
 •   15% of pts with AVM
     experience massive GIT
     bleeding7
      – ~85% stop spontaneously
      – 25-85% will re-bleed
               Anorectal disease

• Massive bleeding encountered in patients with portal HT
                         Aetiology
• Upper GIT Haemorrhage
  – 10-15% of cases of acute rectal bleeding
  – Causes:        Gastritis
                   Gastric / Duodenal Ulcer
                   Oesophageal / Gastric Varices
                   Neoplasia
                   Mallory-Weiss tear
                   Aorto-enteric fistula
                   Osler-Rendu-Weber syndrome
                   (Nasopharyngeal sources)
  - NGT placement mandatory in massive haemorrhage
     - 16% of upper GIT bleeding even if negative gastric lavage8
- Consider gastroscopy
                         Aetiology
• Small intestinal haemorrhage
  –   3-5% of acute rectal bleeding
  –   Diagnosis of exclusion
  –   Localization difficult
  –   Angiodysplasia 70-80%


• Coagulopathy
  – Usually patients with specific mucosal lesions rather
    than spontaneous bleeding9
       • Evaluate as for a patient with normal coagulation
             Sites of bleeding
• R) colon most
  common site of
  bleeding in
  diverticular bleeding
  (70-90%) and
  angiodysplasia
                      Investigation
• Resuscitate (if required) and stabilize

• History
   – NSAIDs, warfarin use
   – Malignancy
   – Bowel habit

• Examination
   – nasopharynx, abdomen, anorectum
      • including DRE and proctosigmoidoscopy
            Faecal Occult Blood Testing
• Normally lose 0.5-1.5mL blood/day from GIT
• Three types of test
   – Guaiac-based (Haemoccult II, Haemoccult II Sensa)
       • Good for detecting large, more distal lesions
       • Inconsistent
            – Need >10mL daily blood loss for +ve test 50% of the time
            – Can detect as little as 1mL of blood in stool
       • Affected by dietary factors
            – Foods which darken stool make it harder to read
            – False positives from dietary iron
   – Immunochemical
       • Do not detect bleeding from upper GIT - localizes to the colon
       • Can detect as little as 0.3mL of blood in stool
       • Lab processing required
   – Heme-porphyrin test
       • Very sensitive
       • High false positive rate
       • Lab processing required
                 FOB testing
• Sensitivity 60-80%
• False positive rate 5-13%

• If test is positive patients require a colonoscopy or
  double-contrast Barium Enema + sigmoidoscopy

• If test is positive and the colon has been “cleared”
  unless iron deficiency is present no further Ix is
  necessary 20
              Barium Enema
• No role in diagnosis of active lower GIT bleeding


• If used will obscure any subsequent attempts to
  visualize by arteriography or colonoscopy


• Double contrast enema has 70% sensitivity in
  elective detection of nonbleeding colonic lesions
                       Colonoscopy
• Diagnostic and therapeutic capabilities
• Can be used even with ongoing massive bleeding
• Characteristic endoscopic findings of recent upper GIT
  h’age are the same as for lower GIT h’age18
   – Active bleeding                - focal adherent clots
   – Nonbleeding visible vessels
• Timing ideally 6-24 hours post presentation
   – Patient must be in stable condition
   – Allows bowel prep
   – This is the time when recurrent bleeding usually occurs
                                   Colonoscopy
• Use of bowel prep debatable
   – Jensen10                      - Sulphate purge (GoLYTELY)             5-6L/3-4hours
   – Caos and Vernava
           11                  1
                                   - GoLYTELY +/- enemas
      •   Scope within 1 hour of completing purge
      •   Up to 86% localization rate
      •   Pts subjected to fluctuations in fluid and electrolyte balance
      •   Large volumes required
                – 4% developed CCF in one 80 patient series



   – Rossini     12
                      - no prep
      • Claim blood effective cathartic
      • Localized 76% in 409 pt series
   – No data yet available regarding safety and efficacy of urgent
     bowel prep in pts with acute bleeding19
                    Colonoscopy

• Increased risk of bowel perforation
   – Should not be attempted with ischaemia or severe mucosal
     inflammation
• Endoscopic coagulation tx of choice for bleeding AVMs
   – 2% risk of perforation
• Diverticular bleeding usually not able to be endoscopically
  coagulated (technically challenging)

• CT Colonoscopy (Virtual colonoscopy)
   – May have a role in assessment of pts with +ve FOB
Bleeding Diverticulum
AVM / post-polypectomy
    haemorrhage
                  Nuclear Scintigraphy
• Detects bleeding ≥0.05-0.1mL/minute                 13




• Two methods
   – Technetium 99m (99mTc) sulfur-colloid
       •   Requires no preparation → inject immediately
       •   Short half life
       •   Enhances liver and spleen → can obscure bleeding sites
       •   Able to detect slower rates of bleeding
   – 99mTc-labeled red blood cells
       • Preferred method
       • Good for intermittent bleeds
       • Able to visualize bleeds near liver/spleen


• 73-98% sensitive
 Diagnostic Accuracy of Technetium 99m-Labeled RBC
             scans for Lower GIT bleeding1

              No. of Studies   Diagnosis made   Correct (%)
                                    (%)
Gupta              45               71              78
McKusick           51               92              83
Kestler            37               30              82
Bentley            98               47              52
Winzelberg         62               94              83
Bunker             41               98              95
Szasz              46               80              81
               380 (total)       73 (mean)      79 (mean)
                Nuclear Scintigraphy
• False localization rate ~20% (3-59%)1


   – Blood does not remain stationary within bowel lumen
       • Reflux into small bowel
       • Rapid transit through bowel with pooling in other areas
       • Redundant sigmoid draping over R) colon masquerades as R) colonic
         bleeding
• Institution dependent
   – Not available in all hospitals
   – Variability in quality
• ?plan surgery on results
• Useful as a prelude to angiography to confirm active
  haemorrhage +/- localization
   – Increased diagnostic accuracy of angiograms in patients with +ve scans


• Not recommended for massive haemorrhage (delays treatment)
        Active bleeding from Ascending Colon


Radiographic Features of
   Abnormal GIT
   bleeding
1. Spontaneous
   appearance
2. Increasing intensity
3. Peristalsis through
   bowel
                     Angiography
• Selective mesenteric angiography
   – Femoral artery punctured
   – Evaluates SMA then IMA then coeliac axis
   – Positive test if extravasation of contrast into bowel lumen
• Can detect haemorrhage rates ≥0.5mL/min           14



• Diagnostic and potentially therapeutic
   – Adrenaline infusion
   – Embolization


• Sensitivity 40-86%
• Complication rate ~ 2%
        Diagnosis of Bleeding Site by Mesenteric
         Angiography in Lower GIT Bleeding             1




                     No. of patients   %Bleeding sites localized

Boley                      43                     65
Leitman                    68                     40
Casarella                  69                     67
Nath                       14                     86
Uden                       28                     57
Welch                      26                     77
Colacchio                  98                     41
Britt                      40                     58
Browder                    50                     72
                          436                     63
Normal selective IMA angiogram
Angiography - bleeding from ileocolic a.
              CT Angiography
•   New and evolving technology
•   Requires modern CT scanner
•   Fast - < 15mins
•   Non-invasive
•   Identifies large and small bowel haemorrhage
•   Sensitivity and specificity 72-80%
                                     17



•   ? Ix of choice in the future
          Obscure GIT bleeding
•   ~5% of patients have bleeding which remains
    unlocalized despite extensive Ix

•   Investigative options
    –   “Push” enteroscopy / Sonde enteroscopy
    –   Capsule enteroscopy
    –   Small bowel follow-through
    –   Meckel’s Scan
    –   Diagnostic laparoscopy
    –   Exploratory laparotomy +/- enteroscopy
                    Enteroscopy
• Requires special instruments
   – “push” Enteroscope
      • 2.7m long thin scope
   – Sonde Enteroscope
      • scope with balloon attached to peristalses through the bowel
   – Paediatric colonoscope use has been reported


• Permits inspection of SB
   – to proximal jejunum with push enteroscopy
   – entire SB with Sonde scope


• ~25% diagnostic yield in reported series15
                  Meckel’s Scan
• Meckel’s diverticulum = remnant of vitellointestinal
  duct
• Disease of 2’s
• only picks up Meckel’s containing gastric mucosa
  (50%)
• 99m-Tc-pertechnetate radioisotope used
   – concentrated mainly by the mucous secretory cells of the
     stomach
• 85% sensitive16
• 95% specific16
• Useful in Ix of young patients with GIT bleeding
                                          References
1.    Vernava A. Lower Gastrointestinal bleeding. Dis Colon Rectum 1997;40:846-858
2.    Vernava A. A nationwide study of the incidence and aetiology of lower GIT bleeding. Surg Res Commun
      1996; 18: 113-20
3.    Rushford A, The significance of bleeding as a symptom in diverticulitis. J R Soc Med 1956; 49:577
4.    Bokhari M. Diverticular haemorrhage in the elderly: is it well tolerated? Dis Colon Rectum 1996; 39:191-5
5.    McGuire J. Massive haemorrhage from diverticulosis of the colon: guidelines for therapy based on bleeding
      patterns observed in fifty cases. Ann Surg 1972; 175:847-53
6.    Robert J. Management of severe haemorrhage in ulcerative colitis. Am J Surg 1990;159:550-5
7.    Reinus J. Vascular ectasias and diverticulosis. Gastrolenterol Clin North Am 1994; 23:1-18
8.    De Markles M. Acute lower GIT bleeding. Med Clin North Am 19993; 77:1085-99
9.    Coon W. Haemorrhagic complication of anticoagulant therapy. Arch Intern Med 1974; 133:386-92
10.   Jensen D. Diagnosis and treatment of severe haematochezia: the role of urgent colonoscopy after purge.
      Gastroenterology 1988; 95:1569-74
11.   Caos A. Colonoscopy after Golytely preparation in acute rectal bleeding. J Clin Gastroenterol 1986;8:46-9
12.   Rossini F. Emergency colonoscopy. World J Surg 1989;13:190-2
13.   Alavi A. Scintigraphic detection of acute gastrointestinal bleeding. Radiology 1977;124:753-6
14.   Vander V. The role of contrast angiography in GIT bleeding with the advent of technetium labeled RBC scans.
      Aust Radil 1985;29:29-42
15.   Chong J. Small bowel push-type fibreoptic enteroscopy for patients with occult gastrointestinal bleeding or
      suspected small bowel pathology. Am J Gastroenterol 1994;89:2143-6
16.   D’Alessandro H. Meckel’s scanning. Virtual Hospital. University of Iowa.
17.   Ernst O. Helical CT in acute lower GIT bleeding. Eur Radiol. 2003 Jan;13(1):114-7
18.   Jensen D. Urgent colonoscopy for the diagnosis and treatment of severe diverticular haemorrhage. N Engl J
      Med 2000;342:78-92
19.   Gostout C. The rope of Endoscopy in Managing acute lower GIT bleeding. N Engl J Med 2000;342:125-127
20.   Rockey D. Primary Care: Occult GIT bleeding. N Engl J Med 1999; 341:38-46