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Barium Enema 1062.e1

Barium Enema
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• Metastasis imaging (three-view thoracic
Difficulty level: ♦
views (45 degrees).
radiographs or thoracic computed tomog- • Obtain lateral, ventrodorsal, and both oblique
Synonym raphy scan; abdominal ultrasound to assess
Large-bowel/rectal contrast study liver, lymph nodes) is indicated if malignancy Postprocedure
is part of the differential diagnosis. • Routine anesthetic recovery
Overview and Goal • Advise the client that it is normal for the
To perform a radiographic contrast procedure Possible Complications and animal’s stools to be loose and gray or pale
that provides information on the gross structure Common Errors to Avoid brown in color for several defecations after
of the colon and rectum. This information Perianal trauma and iatrogenic colonic perfora- the procedure.
may not be available by other routine imaging tion are rare. Use Foley catheter instead of rigid
means; abdominal ultrasound is limited by enema tube. Alternatives and Their Relative Procedures and Techniques
the presence of gas in the colon, and plain Merits
radiography cannot evaluate the mucosal surface Procedure • Colonoscopy has largely replaced barium
of the colon or colonic distensibility. • Before anesthesia, obtain preliminary enemas.
abdominal radiographs to confirm adequate • Abdominal ultrasound: the potential for
Indications animal preparation (colon is as empty as visualizing the structure of the colonic
• Persistent tenesmus possible) and to set radiographic technique. wall may be restricted by the pelvis and by
• Pelvic canal/rectal mass effect on rectal • The barium contrast dose (10 mL/kg) is presence of air in the colon.
palpation and/or on plain radiographs placed into enema reservoir. • Plain radiographs: diagnostic test of choice
• Severe constipation/obstipation not respon- • With the anesthetized animal in right lateral for bony obstruction of the pelvic canal (frac-
sive to simple medical management recumbency, lubricate the catheter, and insert ture, malformation, mass); poor sensitivity
it into the anus sufficiently such that the for soft-tissue lesions of the colon
Contraindications Foley balloon is well beyond the anus and • Colonic biopsy: diagnostic test of choice
NOTE: Organic iodine contrast material (e.g., within the rectum. when a focal or diffuse mucosal lesion is
sodium iothalamate, sodium diatrizoate, diluted • Inflate Foley balloon to reduce or prevent suspected or identified
1 : 1 with water) should be used instead of outflow of contrast from the anus, and gently
barium if rectal or colonic perforation is tug on catheter to bring Foley balloon to seal SUGGESTED READING
suspected, although the contrast effect will be caudally against the anus to prevent contrast Choi M, et al: Imaging assessment of the modified
reduced (p. 1172) leakage. double-contrast barium enema using carboxymeth-
• Slowly administer barium, using gravity for ylcellulose on radiography and ultrasonography in
Equipment, Anesthesia colonic filling (raise the reservoir above the dogs. Vet Radiol Ultrasound 52:648-652, 2011.
• General anesthesia is required; otherwise, animal). AUTHOR: LeeAnn Pack, DVM, DACVR
barium is often expelled from the rectum • After the colon is distended, clamp the EDITORS: Leah A. Cohn, DVM, PhD, DACVIM; Mark S.
by the animal’s straining. infusion tubing to prevent backflow of the Thompson, DVM, DABVP
• Enema bag/set; for smaller animals, large contrast material into the tubing.
syringes may be used instead.
• Barium sulfate suspension with concentration
15%-20% weight per volume
• Foley urinary catheter (e.g., 10-18 Fr tube for
body range of cats to large dogs, respectively)
or Bardex catheter
• Sterile, water-soluble lubricant
Anticipated Time
Approximately 40-60 minutes
Preparation: Important
Checkpoints
• Fecal occult blood testing is highly specific
using o-tolidine–based test kits and may be
performed to further increase an index of
suspicion for a colonic abnormality.
• Prepare an adequate volume of barium. Using
too small of a barium dose is a very common
problem, causing pseudolesions or missing
lesions altogether.
• Barring excessive anal pain, any dog weighing
≥ 6 kg needs to have a simple but complete
rectal palpation before barium enema to
better localize any focal lesions.
• Animal fasted 24 hours A B
• A maximum amount of feces is evacuated
from the colon before the administration of BARIUM ENEMA A, Ventrodorsal projection, normal study. B, Ventrodorsal projection, abnormal study. A
the barium enema. large filling defect in distal colon (arrow) causes marked narrowing of lumen, suggesting a mass lesion.
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