GI and urinary system contrast radiography: Not a dying art (Proceedings)

Agents Used Most Frequently

Contrast media and Use

Barium Sulfate

• Digestive system

Ionic contrast medium

• Vascular

Diatrizoate

• Digestive

Sodium &/or Meglumine

• Urogental

• Intracavitary

• Articular

• Fistula

Non-Ionic contrast medium

• Vascular

Ioxilan

• Urogental

• Fistula

Iohexol

• Central nervous system

• Vascular

• Digestive

• Urogenital

• Intracavitary

• Articular

• Fistula

Gas: Carbon Dioxide

• Digestive

Urogenital

• Intra-cavitary

• Articular

Room air

• Digestive

• Urogenital

• Intra-cavitary

• Articular

Studies to be Discussed

• Digestive System

• Urogenital System

• Intra-Cavitary

Digestive System:

What I have learned from doing digestive system contrast studies:

• Be positive about the procedure even if you use negative contrast medium.

• Prepare the patient and the owner.

• You can not determine esophageal motility status if the pet is sedated or anesthetized.

• You may not be able to determine gastric or bowel motility status if the pet is sedated or anesthetized.

• Administer the contrast medium any place in the hospital except with the patient on the x-ray table.

• If you get barium on your clothing-especially the shoes-wash it off immediately as it is much harder to remove later on.

• A barium/contrast study is either normal or abnormal.

• If it is normal-be happy for the patient-however, it does not mean the GI system is normal.

• If it is abnormal-decide if it is related to a non-obstructive or an obstructive disease process:

Non obstructive:

• Altered bowel dynamics

• Bowel not pathologically distended.

• Bowel wall thickened

• Bowel mucosa irregular

• Barium flocculates

Obstructive:

• Pathological distention of the bowel

• Contrast may not traverse the bowel

Twenty-five percent of the time your exploratory will not reveal a definitive lesion-then biopsy the bowel!

A negative contrast gastrogram is a good way to define gastric pliability, wall thickness/contour and gastric luminal content.

A barium enema is a good way to distinguish between large and small bowel.

Endoscopy, ultrasound and exploratory surgery are often required to make a definitive diagnosis.

Esophogram:

• No sedation or anesthesia

• Obtain survey lateral and VD or VD oblique radiographic projections.

• Place contrast in oral cavity and allow animal to swallow it

• Contrast-

o General evaluation-

• Barium sulfate-1 ml/lb.

o If you suspect esophageal perforation use water soluble medium

• Any water soluble iodinated contrast medium should be good- 1 ml/lb.

• Repeat the radiographic projections immediately

Negeative Contrst Gastrogram:

• Sedation recommended:

Acepromazine IV in Dogs

Ketamine/Valium IV or SQ in cats

• Obtain survey lateral and VD radiographic projections

• Pass the orogastric tube

• Inflate the stomach with room air—6 ml/lb

• Remove the tube and repeat the radiographic projections.

Positive Contrast Gastrointestinal Series

• If sedation needed use acepromazine IV in dogs and ketamine/valium in cats

• Obtain survey lateral and VD radiographic projections.

• Place contrast in the esophagus or into the stomach with an orograstric tube

• Contrast

o General evaluation-use barium sulfate-4ml/lb

o If suspect GI perforation use water soluble iodinated contrast medium-2 ml/lb

• Radiographic projections repeated after contrast administration at the following times:

o Canine: 10 minutes post contrast administration

• 1 hour post contrast administration

• 2 hours post contrast administration

• 4 hours post contrast administration

o Feline: Immediately after contrast administration

• 15 minutes after contrast administration

• 30 minutes after contrast administration

• 45 minutes after contrast administration

• General comments:

A GI series is not completed until a lesion is defined or the majority of the contrast has traversed the bowel. In the canine, radiographs may need to be taken eight hours post-contrast administration or the next day and in the cat, radiographs may need to be taken two hours post-contrast administration to complete the study.

Urogenital

Intravenous urogram

• Make sure colon and urinary bladder are empty

• Obtain survey lateral and VD radiographs

• Place a catheter in the cephalic vein

• Place a catheter in the urinary bladder

• Inject water soluble contrast medium intravenously-1ml/lb

• Obtain radiographs within one to two minutes after injection (lateral, VD and oblique projections as needed)

• Distended the urinary bladder with gas-4ml/lb

• Obtain radiographs five minutes after the bladder is distended (lateral, VD and oblique projections as needed)

• Obtain radiographs ten-fifteen minutes after bladder is distended.

Negative contrast cystogram

• Make sure the colon is empty

• Obtain survey lateral and VD oblique radiographs

• Place catheter in the urinary bladder

• Distend the bladder with gas-4 ml/lb.

• Obtain lateral and VD oblique radiographs

Positive contrast cystogram

• Make sure the colon is empty

• Obtain survey lateral and VD oblique radiographs

• Place catheter in the urinary bladder

• Distend the bladder with water soluble iodinated contrast medium –2 ml/lb.

• Obtain lateral and VD oblique radiographs

Double contrast cystogram

• Make sure the colon is empty

• Obtain survey lateral and VD oblique radiographs

• Place catheter in the urinary bladder

• Place a small amount of water soluble iodinated contrast medium into the bladder 1 ml for cat, 2 ml for small dog, 3 ml for medium size dog, 4 ml for large size dog or 5 ml for giant size dog (note this is total volume, not per pound)

• Distend the urinary bladder with gas-4 ml/lb

• Obtain lateral and VD oblique radiographs

Positive contrast urethrogram

• Make sure the colon is empty

• Obtain survey lateral and VD oblique radiographs

• Fill the catheter with positive contrast medium

• Place the catheter into terminal portion of urethra

• Secure the catheter in place

• Inject positive contrast medium 5 ml for small dog or cat

• 10 ml for medium size dog; 15 ml for large or giant size dog

• Obtain lateral radiograph while completing injection

• Repeat the injection

• Take VD oblique radiograph while completing the injection

Positive contrast vaginogram

• Make sure the colon is empty

• Obtain survey lateral and VD oblique radiographs

• Fill the catheter with positive contrast medium

• Place the catheter into terminal portion of the vagina

• Secure the catheter in place

• Inject positive contrast medium 5 ml for small dog or cat

o 10 ml for medium size dog; 15 ml for large or giant size dog

• Obtain lateral radiograph while completing injection

• Obtain VD oblique radiograph.

Positive Contrast Peritoneogram

• Obtain survey lateral and VD radiographs

• Sedate the animal

• Place a catheter into the abdominal cavity-catheter should be inserted adjacent to the umbilicus and just to the right of the midline.

• Inject sterile water soluble contrast medium into the peritoneal cavity-1 ml/lb

• Remove the catheter

•Massage the abdomen to distribute the contrast medium.

• Obtain lateral and VD or DV radiographs.

• General comments:

o If free fluid is present in the abdomen, remove as much of the fluid as you can before injecting the positive contrast medium

o If you suspect a hernia, position the animal for three minutes so that the positive contrast medium will flow towards the suspected hernia site.

o The positive contrast medium will be absorbed and you will eventually see it in the kidneys and urinary bladder.