Contrast media

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Author: Mikael Häggström [notes 1]

Intravenous

CT

Main article: CT with IV contrast

Contrast medium reaction

Main article: Contrast medium reaction

In a more severe reaction:[1]

  • Adrenaline shot, 0.3-0.5mg in adults, given intramuscularly.
  • Summon an anesthesiologist
Intramuscular site of adrenaline.jpg
Prevention
Main article: Prevention of contrast medium reaction

Before a contrast CT of a patient with known allergic-like or unknown-type of contrast reaction to the same class of contrast medium (such as iodinated), the American College of of Radiology recommends premedication with a glucocorticoid, preferably starting 12 or 13 hours before contrast administration.[2]

In low renal function

Main article: CT with IV contrast in low renal function

Decreased renal function and several other conditions increase the risk of contrast-induced nephropathy, which is a potentially lethal renal injury to the kidney following intravenous radiocontrast.[3]

Peroral

Rectal

Projectional radiography and fluoroscopy

Choice of contrast medium
  • Barium sulfate is generally used.
  • An iodine-based contrast medium is used where there is a risk perforation, where barium may cause chemical inflammation.<[4]
However, 1-2% of oral iodine is absorbed in the gastrointestinal tract, and can potentially case a contrast medium reaction.[5] Also, it is more expensive than barium
Iodine-based

Recommended concentration:

Adults: 70 mg iodine per ml, such as 240 ml of a 370mg/ml solution in 1,000 mL of tap water.[notes 2]
Children over 5 years: 55 mg iodine per ml such as 90 ml of a 370mg/ml solution in 500 mL tap water.[notes 2]

CT scans

Rectally administered contrast is indicated in cases where a suspicion remains of penetrating trauma to the colon where an initial CT shows no reason for immediate surgery.[6]

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Radlines:Authorship for details.
  2. 2.0 2.1 370mg/ml for undiluted gastrografin: Dosages:

References

  1. Unless otherwise specified in lists and table: . Hypersensitivity reactions against contrast media - Swedish Society of Uroradiology [Swedish: Överkänslighetsreaktioner mot kontrastmedel – SURFs kontrastmedelsgrupp ], 2014-10-17].
  2. Error on call to Template:cite web: Parameters url and title must be specified. . American College of Radiology, Committee on Drugs and Contrast Media. Retrieved on 2018-08-25. Version 10.3. 2018. ACR
  3. Rudnick, M.; Feldman, H. (2008). "Contrast-Induced Nephropathy: What Are the True Clinical Consequences? ". Clinical Journal of the American Society of Nephrology 3 (1): 263–272. doi:10.2215/CJN.03690907. ISSN 1555-9041. 
  4. Dr Vikas Shah ◉ and Dr Jeremy Jones. CT luminal contrast. Radiopaedia. Retrieved on 2018-11-07.
  5. . Oral Contrast Policies. Yale School of Medicine. Retrieved on 2018-11-07.
  6. Stephen Ledbetter and Robin Smithuis (2007-08-02). Acute Abdomen - Role of CT in Trauma. Radiopaedia.