Rectal bleeding

Question 1

What is fresh rectal bleeding a cause of?

Answer 1

Results from a source in the rectum or colon

Question 2

What are common causes of acute lower GI bleeds?

Answer 2

Diverticular disease
Ischaemic or infective colitis, haemorrhoids
Malignancy
Angiodysplasia
Crohn’s disease or Ulcerative colitis
Radiation proctitis

Question 3

What is the most common cause of lower GI bleeding?

Answer 3

Diverticulosis

Question 4

What is diverticulosis?

Answer 4

Outpouchings of the bowel wall that are composed only of mucosa, most commonly in the descending and sigmoid colon

Question 5

What are key facts about diverticulosis?

Answer 5

The incidence of diverticulosis increases with age. Diverticular disease bleeds are classically painless, whilst diverticulitis associated bleeds are often painful, secondary to the localised inflammation.

Question 6

What are haemorrhoids?

Answer 6

Vascular cushions in the anal canal that can present as a mass, with pruritus, or fresh red rectal bleeding

The blood is classically on the surface of the stool or toilet pan, rather than mixed in with it

Large haemorrhoids can also thrombose, which can be extremely painful.

Question 7

What would you ask about malignancy when suspected?

Answer 7

Ask about other lower GI symptoms, weight loss, or relevant family history, potentially suggestive a diagnosis of malignancy.

Question 8

What score can you suggest to stratify patients with rectal bleeds?

Answer 8

Oakland score

Factors used to determine the Oakland score are Age, Sex, Previous Admissions for Lower GI bleeding, PR findings, Heart Rate, Systolic Blood Pressure, and Haemoglobin Concentration.

Question 9

What do patients with stable bleeds need?

Answer 9

Patients with stable bleeds will require a flexible sigmoidoscopy (or colonoscopy) for further assessment, importantly to exclude left-colonic pathology (especially malignancy) and can often be performed as an outpatient.

In stable patients with PR bleeding and no abnormality identified on colonoscopy, upper GI endoscopy (OGD) should be performed to look for further sources of bleeding. If this proves inconclusive, further investigations such as capsule endoscopy or MRI small bowel scans may be required.

Question 10

How would you manage PR bleeds?

Answer 10

95% of cases will settle spontaneously. Often young haemodynamically stable patients, in who the bleeding has stopped and have a low risk score, can be discharged and investigated as an outpatient.

Any unstable rectal bleed warrants urgent resuscitation, with a standard A to E approach, using IV fluid and blood products as required until stabilised

Any Hb <70 should trigger transfusion of packed red blood cells

Question 11

If management is required, what would you do?

Answer 11

Endoscopic haemostasis methods include injection (typically diluted adrenaline), contact and non-contact thermal devices (such as bipolar electrocoagulation or argon plasma coagulation), and mechanical therapies (endoscopic clips and band ligation)

Arterial embolisation is possible in those with an identified bleeding point (termed a “blush”) of sufficient size on angiogram

Surgical intervention is rarely required, however may be considered in patients with ongoing lower GI bleeding with instability (or requiring continued transfusion), where endoscopic and radiographic treatment has failed.

Question 12

What would you do in haemodynamically unstable PR bleed patients?

Answer 12

Patients should be initially stabilised before undergoing an urgent CT angiogram (before any endoscopic therapy). This can identify the source of bleeding, as well as permitting potential therapeutic intervention with embolisatio

Question 13

What are three important categories of questions to ask patients with PR bleeds?

Answer 13

1. Nature of bleeding
2. Associated symptoms, including pain (especially association with defaecation), haematemesis, PR mucus, or previous episodes
3. Family history of bowel cancer or inflammatory bowel disease

Examine the abdomen for any localised tenderness or masses palpable. A PR examination is essential for every patient presenting with haemotochezia, allowing assessment for any rectal masses and ongoing presence of blood.

Question 14

What are key points about PR bleeds?

Answer 14

1. Any patient with rectal bleeding required a flexible sigmoidoscopy or colonoscopy
2. A patient with a large fresh rectal bleed who is haemodynamically unstable has an upper GI bleed until proven otherwise
3. Acute bleeds may not initially show an anaemia in the full blood count
4. Patients who are haemodynamically unstable need an emergency OGD and colonoscopy