GI - Rectal bleeding investigations

Question 1

(4) types of rectal bleeding

Answer 1

• overt red bleeding
• malaena
• massive/acute bleeding
• occult bleeding

Question 2

What is massive/acute rectal bleeding?

• consequence
• prognosis
• sources

Answer 2

Substantial bleeding that creates haemodynamic instability -> requires admission & transfusion.

Early cessation usual but 15% continue to bleed/rebleed.

Most cases due to a (right sided) colonic source; diverticular disease, angiodysplasia.

Up to 25% cases due to small bowel pathollogy.

Occasional cases due to rectum: due to briskly bleeding GI problem.

Question 3

A negative nasogastric tube aspirate when looking for stomach bleeding:

Answer 3

does not rule out bleeding from the stomach. the blood may have clotted and unable to be aspirated.

Question 4

Mx of massive/acute rectal bleeding

Answer 4

• resuscitation
• reversal of anticoagulation
• elective colonoscopy
• CT angiogram, nasogastric tube, sigmoidoscopy,

Question 5

Describe occult bleeding

Answer 5

• screen detected (FOB)
• can Px as anaemia (severe menorrhagia, coeliac, vegans, alcoholics, carcinoma of caecum, poor nutrition)
• colonoscopy is mandatory for both
• other tests if colonoscopy negative

*Fecal occult blood test is a screening tool and NEVER a diagnostic test

Question 6

Causes of overt rectal bleeding

Answer 6

Anorectal: haemorrhoids, fissure
Colorectal: cancer, plyps, colitis

Question 7

Causes of anaemia

Answer 7

severe menorrhagia, coeliac, vegans, alcoholics, carcinoma of caecum, poor nutrition, GI bleeding, any blood loss

Question 8

Appearance of rectal prolapse

Answer 8

4-6cm in length, eccentric, one sided, rounded

Question 9

What are haemorrhoids?

• structure
• Px
• worse with…
• Rx

Answer 9

bunch of arterioles (NOT venous c.f. rectal venous varices in portal HTN).

May bleed, prolapse or thrombose.
Blood is bright red in the toilet bowl/paper, not mixed in the stool.
Worse when constipated & straining.

Rx: high fibre diet (15g/day) first line. If failed, consider banding/surgery.

Question 10

Describe anal fissure

• Px
• 2 types of pain

Answer 10

• Px: rectal bleeding (usually less than haemorrhoids)
• common, very painful
• 2 types of pain: severe sharp tearing pain on defecation & dull ache for 1-2 hours afterwards (muscle/sphincter spasm)

Question 11

Appearance of bowel cancer inside bowel.

• Px
• colour of blood

Answer 11

Mass lesion, everted edges, central ulceration

Can Px with bright rectal bleeding but usually DARK red bleeding + blood within the stool.

Malignant bowel bleeding is dark, as they invade veins.

Question 12

Describe anal wart

• cause
• anal cancer type
• Rx

Answer 12

Due to HPV
Anal cancer is SCC (tiny proportion of GI malignancy)
Rx: radiotherapy + chemotherapy WITHOUT surgery. Better prognosis (80% cure rate)

Question 13

What should you ask in a rectal bleeding Hx?

Answer 13

• colour of blood
• anorectal symptoms (pain, anal swelling)
• colorectal symptoms (change in bowel habit, unsatisfied defaecation, passage of mucus)
• how long
• FMHx

Question 14

How do you do an anal inspection?

Answer 14

• good lighting
• left lateral
• slow gentle movements (even parting the buttocks can hurt a fissure pt)
• look for: fissures, haemorrhoids, thrombosed perianal haematomas, fistula, warts, anal cancer

Question 15

How do you perform a DRE?

Answer 15

Use pulp not tip of finger, gentle.

Contemplate:

• character of mucosa
• presacral space
• gently increasing pressure can reach 10cm in most
• cervix can be a trap (the rectal mucosa is normal overlying the hard cervix)
• feel for prostate
• check for blood on the glove

Question 16

What rectal bleeding should you be concerned about?

• colour
• stool
• mucus
• change in bowel habits
• age
• FMHx

Answer 16

• dark marroon
• mixed
• mucus present
• change in bowel habits
• > 40yo
• FMHx positive

Question 17

How does R colon cancer present?

Answer 17

Anaemia, mass

Question 18

How does L. colon cancer present?

Answer 18

• alternating constipation and diarrhoea
• constipation only
• colicky lower abdo pain
• dark blood in stool

Question 19

How does rectal cancer present?

Answer 19

• rectal bleeding; dark but sometimes bright
• unsatisfied defaecation
• passage of mucus

Question 20

Prognosis of bowel cancer

Answer 20

Five year survival depends on ACPS grading (A-D) ranges from 90% to 5%.

Question 21

Indications for colonoscopy

Answer 21

• rectal bleeding: persistent, dark bleeding, >40yo
• change in bowel habit
• iron deficiency anaemia
• screening: positive FOBT
• surveillance: e.g. positive FMHx

Question 22

How do you Rx anal fissure?

Answer 22

GTN in anus. 3 times a week for 3 weeks -> review.

See if symptoms have resolved, if not, look further for any other causes of bleeding e.g. colonoscopy

Question 23

Bowel cancer screening in Australia currently

Answer 23

5 yearly fecal occult blood test (FOBT) from 50yo. (but the evidence is every 2 yearly) -> 2 yearly test from 2020.

$7 per test