• Very common surgical referral
• Seen mainly in the elderly
• Underlying cause is influenced by age
• rarely requires surgical intervention (at least in the acute phase)
• Essential to establish a good history from the patient and/or relative as to the amount and colour, clots, duration, mixed with stool or separate, in the pan or on the toilet tissue, any other symptoms e.g. pain, melaena/haematemesis, pruritis ani, tenesmus, urgency, weight/appetite loss, family history of cancer, change in bowel habit from normal for them, urinary symptoms etc.

Possible Causes

• Diverticular Disease
• Angiodysplasia  
• Ischemic colitis  
• Radiation-induced colitis/proctits (esp in men with Rx for prostate cancer) 
• Rectal or colonic cancer
• Ischaemic colitis
• Infectious colitis 
• Inflammatory Bowel Disease
• Idiopathic colitis  
• Anorectal causes  
  • hemorrhoids
  • fistula
  • fissures
  • polyps
• Drug-induced bleeding is caused mainly by NSAIDs
• Other vascular causes 
  
  • polyarteritis nodosa
  • Wegener granulomatosis
  • Aortocolonic fistula (post AAA surgery)

Investigations

• As most patients tend to be stable they can be investigated once bleeding has stopped as an outpatient
• In the actively bleeding patient consider:
  • Colonoscopy - experienced endoscopist required
  • Upper GI endoscopy for brisk bleeds
  • Selective mesenteric angiography - experienced radilogist required andthe above need to be done first

Initial Management

1. May need rapid resuscitation if bleeding heavily (see massive upper GI bleed)
2. If bleeding ++ and bright red there is a good chance it is from an upper GI source – get hold of the on-call endoscopist ASAP
3. Large venflons & Crystalloid infusion
4. Check HB, U&E, Clotting
5. Check for PMH of Crohn’s / Colitis, recent foreign travel etc
6. Do a PR
7. If bleeding ++ call a senior
8. Catheterise

Continuing Management

1. If bleeding ++ and once an upper GI source has been excluded then a mesenteric angiogram is required. 
2. Blind colectomy has no place as there is a good chance the wrong piece of bowel will be removed, and access to localising investigations is much easier now than in years gone by.
3. There is a potential role for on-table lavage and pan-endoscopy