Lower GI bleed

• Lower gastrointestinal bleeding (LGIB) classically refers to bleeding that occurs distal to the ligament of Treitz.
• Anatomical causes:

  • Diverticulosis - painless unless diverticulitis
  • Haemorrhoids
  • Anal Fissures
  • Anal fistulas
• Vascular causes:

  • Ischaemic colitis
  • Angiodysplasia - presence of AVM
• Neoplastic causes:

  • Polyps
  • Malignancy
• Inflammatory causes:

  • IBD
  • Infective - bloody diarrhoea
• Bedside

  • Digital rectal examination
  • Observations
  • Lying / standing blood pressure
  • Blood glucose
  • ECG
  • Stool microscopy, culture & sensitivities
  • Faecal calprotectin
• Bloods

  • Full blood count
  • Urea & electrolytes
  • Liver function tests
  • Haematinics
  • Clotting
  • Arterial / venous blood gas
  • Group and saves +/- cross-match
• Imaging

  • Erect CXR: to look for evidence of free air under the diaphragm indicative of hollow viscus perforation.
  • CT abdomen/pelvis: CT may be ordered to identify the underlying diagnosis, e.g if a large colonic malignancy is suspected or to look for evidence of ischaemic colitis.
  • CT angiography: CT angiogram may allow identification of a bleeding point - typically only in patients with brisk active bleeding.
• Special

  • Flexible sigmoidoscopy
  • Colonoscopy
  • Upper GI endoscopy (e.g. if UGIB suspected)
  • Angiographic transarterial embolisation
• Shock index is HR/SBP

  • SI <1 = stable GI bleed
  • SI >1 = unstable or suspected active
• The oakland score should be calculated in stable lower GI bleed patients to assess risk

  If >8 they should be admitted for monitoring and endoscopy as an IP
• Patients with unstable GI bleeding (SI > 1) or suspected active bleeding should have a CT angiogram organised.

  This may identify an area of active bleeding (extravasation of contrast) that may be treated by interventional radiology (IR) with embolisation or with endoscopic techniques.