Rectal bleeding 2 Flashcards
What do you look for on general examination of rectal bleeding?
- Haemodynamically stable?
- Signs of chronic blood loss?
- Signs of malignancy?
How do you check if patient is haemodynamically stable?
pulse and BP for signs of continuing or new bleeding
What would signs of chronic blood loss be?
signs of anaemia e.g. extreme pallor or koilonychia
What would signs of malignancy be?
cachexia or obvious lympahdeopathy
What do you look for on abdominal exam in rectal bleeding?
focal tenderness or masses: signs of GI malignancy e.g.
- left supraclavicular lympahedopathy
- palpable lesions of colon
- hepatomegaly
- ascites
What do you do during a rectal exam?
- Inspect anus
2. DRE
What do you inspect for on the anus?
- anal fissure
- skin tag
- setinel pile
- heamorroid
- fistula
When do you not do a DRE?
presence of painful anal fissure or abscess
Why do you carry out a DRE?
feel for palpable masses and inspect blood on withdrawn gloved finger
When can you feel haemorrhoids on a DRE?
if prolapsed or thrombosed
What bloods do you carry out for rectal bleeding?
- FBC
- Clotting
- Group and Save
- Urea
Why do you look at FBC in rectal bleeding?
check for anaemia and low platelets (from chronic blood loss)
Why do you measure clotting in rectal bleeding?
check if patient has a bleeding tendency
Why do you do a group and save in rectal bleeding?
if patient need blood replacement or may need to go to theatre - or a cross match if urgent
Why do you check urea in rectal bleeding?
raise in urea in recent upper GI bleed (urea is a breakdown product of digested rbc)
What endoscopy do you always perform?
protoscopy ± rigid sigmoidscopy
When would you not peform a protoscopy ± rigid sigmoidscopy?
painful anal lesion
What are the downsides of protscopy ± flexible sigmoidscopy?
if too much blood visualistion of rectum may be poor
What are the advantages of protscopy ± flexible sigmoidscopy?
- enable identifcation of bleeding haemorrhoids or a rectal cancer
- can be done at bedside
What are some further main investigations for acute lower GI haemorrhage (frank blood per rectum) that can be considered in stable patients?
- Colonscopy
- Mesenteric angiography
- CT angiography
- Technetium-99 m-labelled RBC scintigraphy (if available)
What are advantages of colonscopy?
- Diagnostic
2. Can be therapeutic
How can a colonscopy be therapeutic?
- control local haemorrhage by adrenaline injection
- argon plasma coagulation
- diathermy
- clipping
What are the disadvanatges of rectal bleeding?
- Need to prepare bowel
2. Invasive
How can you improve visualisation for colonoscopy?
colon can be irrigated via caecal catheter
When is mesenteric angiography used?
if haemorrhage obscures view for colonscopy or colonscopy not possible - used in patients that blled, then stop, then bleed
What is mesenteric angiography useful to visualise?
angiodysplasia
Is mesenteric angiogrpahy widely avilable?
no
How can mesenteric angiography be therapeutic?
embolization of bleeding vessel can be peformed during procedure
Why is CT angiography useful?
multislice CT can detect even minor bleeds
Why is CT angiography better than mesenteric angiography?
- Venous access not like arterial in mesenteric so fewer complications
- Provides rapid imaging and enables other abdominal pathology (related or incidental) to be seen
What are the disadvantages of CT angiography?
- no therapeutic opportunity so may need mesenteric or laparotomy
- involves contract so contradindicated in patients with significant renal impairment
When is Technetium-99 m-labelled RBC scintigraphy useful?
for patients where source of bleeding haven’t been able to be identified - short lived intermittent bleeds e.g. from Meckel’s diverticulum
Is Technetium-99 m-labelled RBC scintigraphy widely available?
no
What are the disadvantages of Technetium-99 m-labelled RBC scintigraphy?
- lacks specificity of colonoscopy and mesenteric angiography
- no therapeutic potential
What are the advantages of Technetium-99 m-labelled RBC scintigraphy?
- non-invasive
- can detect bleeding lesions up to 24hr after tracer administration
- no bowel prep needed
What is the imaging algorithm for stable patient with rectal bleeding?
- Protoscopy +/- rigid sigmoidscopy
- colonscopy
- Mesenteric angiography / CT angiography
- Radionuclide imaging
When would you do an upper GI endoscopy?
if history and exam suggests 80% of acute GI haemorrhage is upper
Why is small bowel visualisation by enteroscopy or video capsule endoscopy not used very often?
limited usage in acute lower GI haemorrhage
Which conditions have classic causes of intermittent bleeding can be difficult to visualise?
Angiodysplasia and Dieulafoy lesion
What is colonic angiodysplasia?
submucosal ateriovenous malformation
What the cause of angiodysplasia?
unknown but predominance in right colon suggests that high wall tension may be factor
How big are the lesions in angiodysplasia?
usally less than 1cm in diameter but can bleed out of proportion to size
What sort of blood loss is in angiodysplasia?
venous blood loss
How does angiodysplasia look on endoscopy?
charactersitic ‘cherry red spot’ (sometimes too much blood tho)
How can angiodysplasia present?
with frank rectal bleeding or occult blood loss and subsequent anaemic symptoms
What is the best imaging for angiodysplasia?
mesenteric angiography
What is the treatment of angiodysplasia?
- embolization
- surgical resection
- endoscopic laser electrocoagulation
What sort of blood loss is in haemorrhage from colonic diverticular disease?
arterial from vasa recta
