Content in this module contains material previously published as the modules Iodinated Contrast Media Pt 1: Pharmacology, and Iodinated Contast Media, Pt 2: Adverse Reactions. If you have alerady completed either or both of these modules, you are not eligible to take this new course for CE credit.

This module describes routes by which contrast media are administered and explains the molecular construction of tri-iodinated benzene salts, their properties and the basis for their classifications. The concept of osmolality is explained and is followed by a thorough review of common adverse effects, distinguishing physiologic and nonphysiologic mechanisms. Finally, the module addresses the importance of patient medical histories in alerting radiologic personnel to increased risk for adverse events. Course Approval Expiration/End Date: August 1, 2010 Category A Credit.

This activity may be available in multiple formats or from different sponsors. The ARRT does not allow CE activities such as internet courses, home study programs or directed readings to be repeated for CE credit in the same or any subsequent biennium.

• Describe the routes by which contrast media are administered and distinguish the influence of positive and negative contrast media on tissue density.
• Explain why iodine is used in contrast media and describe the molecular construction of tri-iodinated benzene salts.
• Name and define the four major properties of contrast media, and explain why warming contrast media makes it easier to inject.
• Explain the concept of osmolality and how it is calculated.
• Explain the classification of iodinated contrast media in terms their primary characteristics and how these are used to compute their iodine:particle ratio.
• Recognize the impact of osmolality of a contrast medium and its correlation to adverse reaction incidence.
• Identify and describe adverse physiologic reactions attributed to contrast media, including their association with the vasovagal response.
• Describe clinical features of allergic or pseudoallergic reactions, and distinguish their pathogenesis.
• Offer specific medical histories that should alert radiologic personnel to the potential for a patient to have adverse reactions to iodinated contrast media.
• Explain the basis for concern regarding the use of iodinated contrast media in patients treated with metformin (Glucophage).

Brasch RC. The case strengthens for allergy to contrast media [editorial]. Radiology. 1998; 20935-6.

Coakley FV, Panicek DM. Iodine allergy: An oyster without a pearl? AJR 1997;169:951-2 Cochran S, Bomyea K, Sayre JW. Trends in adverse events after IV administration of contrast media. AJR 2001;176:1385-88.

Dawson P. Radiological contrast agents. Applied Radiology (Sup) April 2002 pp45-54. Guyton AC, Hall JE. Textbook of Medical Physiology, 11th ed. Philadelphia, Pa: WB Elsevier SaundersSaunders; 19962006.

Herrera AM; deShazo RD. Current concepts in anaphylaxis. Pathophysiology, diagnosis, and treatment. Immunol Allergy Clin North Am. 12:517-34; 1992

Katzberg RW. The contrast media manual. Baltimore: Williams & Wilkins; 1992.

Laroche D; Aimone-Gastin I; Dubois F, and et al. Mechanisms of severe immediate reactions to iodinated contrast material. Radiology. 1998; 209(183-190).

Lasser EC. Pseudoallergic drug reactions. Radiographic contrast media. Immunol Allergy Clin North Am. 1991;11(3):645-657.

Lieberman PL, Seigle RL. Reactions to radiocontrast material: Anaphylactoid events in radiology. Clin Rev Allergy Immunol. 1999;17(4):469-496.

Marenzi G, Assanelli E, Marana I, et al. N-Acetylcysteine and Contrast-Induced Nephropathy in Primary Angioplasty. N Engl J Med 2006;354(26):2773-2782

Mita H, Tadokoro K, Akiyama K. Detection of IgE antibody to a radiocontrast medium. Allergy 1998;53:1133-40

Olin BR, Hebel SK, Dombek CE, eds. Drug Facts and Comparisons. 2006 2007 ed. St Louis, Mo: Facts and Comparisons; 20042007.

Sandler CM. Contrast-induced acute renal dysfunction: Is iodixanol the answer? N Engl J Med 2003;348(6):551-3

Stellato C, Adkinson Jr NF. Pathophysiology of contrast media anaphylactoid reactions: new perspectives on an old problem. Allergy 1998;53:1111-13.

Tramer MR, et.al. Pharmacological prevention of serious anaphylactic reactions due to iodinated contrast media: systematic review. BMJ 2006;333:675-; originally published online 31 Jul 2006; doi:10.1136/bmj.38905.634132

Webiography:

General Info
Oldnall N. xray2000 Nicks website. Contrast Media and Drugs used in the Department: A Simple Guide to the basics. March 27, 2007. Available at: http://www.xray2000.co.uk/. Accessed April 4, 2007.

Radiology InfoNet, Inc. RADIOLOGYinfonet Homepage. 2006. Available at: http://www.radinfonet.com/. Accessed April 4, 2007.

Properties of Contrast Media
Kimball JW. The Kidneys. May 5, 2005. Available at http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/K/Kidney.html. Accessed April 4, 2007.

Osmosis
Colorado State University Hypertexts for Biological Sciences. Osmosis. July 2, 2000. Available at: http://arbl.cvmbs.colostate.edu/hbooks/cmb/cells/pmemb/osmosis.html. Accessed April 4, 2007.

Adverse Reactions
University of Alabama Hospital Department of Radiology. FAQs. Visions Newsletter Volume 2 Numer 2 1996. Available at: http://www.rad.uab.edu/Visions/Summer96/Summer96.htm#anchor718065. Accessed April 4, 2007.

Physiologic or Chemotoxic Reactions
Society for Neuroscience. Brain Briefings. Blood-Brain Barrier. 2007. Available at: http://www.sfn.org/index.cfm?pagename=brainBriefings_bloodBrainBarrier. Accessed April 4, 2007.