DCBE

Question 1

what does DCBE stand for?

Answer 1

double contrast barium enema

Question 2

what can be examined in a DCBE?

Answer 2

the colon, rectum and caecum - the large bowel

Question 3

what its the first line diagnostic test?

what is an alternative method?

Answer 3

Virtual colonoscopy for visualisation of colon disease

CT colonography

Question 4

what is involved in double contrast?

Answer 4

barium and gas

Question 5

what is the aim of the double contrast

Answer 5

to image the entire large bowel - the barium coats the wall and the gas helps distend the bowel facilitating a fine coat of barium on the bowel mucosa and acts in extreme contrast with the dense barium suspension

Question 6

what is the patient preparation for a DCBE

what are the side effects?

Answer 6

cleaning of the bowel with a low residue diet and laxatives 48 and/or 24 hrs before
the laxative (Picolax) has a osmotic (dehydrating) effect on the patient making faeces ‘watery’ to pass rapidly but this is dangerous and fluid intake should be encouraged - also as a result patients may experience headaches, tiredness and abdominal pain
this ensures no faecal remnants mask any pathology or are misleading presenting similar to a pathology

Question 7

what are the contraindications for the use of a laxative agent? - 4 points

Answer 7

acute surgical conditions
severe dehydration
toxic megacolon
ulcerative colitis

Question 8

what 2 things should be discontinued before a DCBE?

Answer 8

iron tablets - may cause constipation

bran supplements - remain within GIT preventing optimum cleansing of the bowel

Question 9

what additional patient prep is carried out? - 6 points

Answer 9

ID check
change into gown and fully explain procedure
remove any artefacts
check patient history and medication
LMP
safety checklist - effectiveness of bowel prep, use of bucopan, allergies etc.

Question 10

what can be given to reduce bowel spasms

when is it contraindicated

what is given instead

Answer 10

a muscle relaxant = Buscopan
intravenously injected in the median cubital fossa

patients with known close-angled glaucoma and cardiac disease (heart or eye problems)

Glucagon

Question 11

what is the positive contrast agent used

Answer 11

barium sulphate suspension - a measure amount of warm water (to decrease risk of bowel spasm and patient discomfort) is added to the barium powder to ensure a high density and low viscosity suspension

Question 12

additional equipment for a DCBE - 10 points

Answer 12

funnel to fill enema bag with water (unless using a pre-mixed kit)
rectal catheter with gas insufflation bag  
drip stand for barium bag
gas insufflation device (hand balloon)
lubricating jelly
gauze swabs
adhesive tape (for positioning catheter)
gloves
muscle relaxant
needle and syringe

Question 13

what are the clinical indications for a DCBE? - 7 points

Answer 13

rectal bleeding
altered bowel habit
tenesmus
palpable abdominal mass
left iliac fossa pain
iron deficiency anaemia
polyp/tumour noted during colonoscopy

Question 14

what are the contraindications for DCBE? - 9 points

Answer 14

pregnancy
recent rectal biopsy (bowel wall will be compromised and there is potential for perforation)
colitis (bowel wall = inflamed and barium could irritate and worsen symptoms)
acute gastrointestinal bleeding
severe rectal inflammation
complete LBO
suspected perf (water soluble agent used)
buscopan contraindications (glaucoma, tachycardia, megacolon)
incomplete bowel prep

Question 15

what are the side effects of DCBE? - 3 points

Answer 15

bloating & digestive discomfort
constipation
dehydration

Question 16

What are rare side effects of DCBE? - 4 points

Answer 16

bowel perforation (incorrect catheter placement)
barium impaction (causes LBO)
allergic reaction (to latex balloon)
blurred vision (Buscopan)

Question 17

Describe a DCBE procedure introducing positive contrast agent - 7 points

Answer 17

patient lies on left side with knees and hips flexed

lubricated catheter is inserted into rectum and secured in place

Buscopan (or Glucagon) administrated at this point or prior to negative contrast agent

barium sulphate solution administered from enema kit held on drip stand - run into patient’s colon via rectum and bowel is screened with fluoroscope

table (initially horizontal) can be angled into Trendelenburg position to allow coating of mucosa

when barium solution reaches splenic flexure/mid transverse colon, barium clamped and patient moved into different positions to coat mucosal linings

barium drained back into bag and negative contrast agent introduced

Question 18

describe a DCBE procedure introducing negative contrast agent 5 points

Answer 18

introduced through insufflator - helps bowel to distend and ‘push’s barium coating further round the bowel as far as the ileo-caecal valve

varius ‘spot images’ captured to ensure all anatomy is demonstrated (rectum, sigmoid, descending/transverse/ascending colon, splenic/hepatic flexure, caecum)

table may be moved into vertical position for erect oblique images of both flexures - care so patient doesn’t fall or injure whilst table is moving

over-couch projections may be taken using over-couch tube to ensure complete visualisation of the region - lateral rectum, lateral decubitus abdomen (PA and/or AP), prone abdomen (30-35% caudal angulation to demonstrate sigmoid colon)

once required images taken, enema tube removed, patient escorted to the toilet to evacuate remaining barium and air - approx 20 mins

Question 19

what is the aftercare for DCBE - 4 points

Answer 19

ensure patient doesn’t leave until blurring of vision is resolved (due to Buscopan on smooth muscle fibres affecting vision) - usually lasts no longer than an hour

aware of possible ‘white stools’

resumes normal diet but encourage drinking plenty of fluids and eat high fibre foods (to avoid constipation)

aware how to access examination results