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Purpose: Radiology residencies are increasingly using clinical simulation to teach contrast reaction management. The aim of this study was to evaluate resident documentation of management and transfer of care in severe contrast reactions after a clinical simulation., Methods: After a high-fidelity mannequin simulation of contrast-induced anaphylactic shock, residents (n = 18) were asked to document the event in a progress note and transfer care to a receiving medical team. A total of 22 prospectively determined criteria were selected, and notes were analyzed by a blinded reviewer., Results: Notes contained between 12 and 21 of the prospectively determined 22 criteria (54%-95%). The median number of criteria contained in a note was 16. None of the notes fulfilled all 22 criteria. However, consistent deficiencies were found in documenting prior reaction to contrast (28%) and transfer-of-care criteria (22%-44%)., Conclusions: Although standards for the documentation of advanced cardiovascular life support codes and other emergencies have been devised, no such standards exist for documentation in the management of contrast reactions. The results of this study suggest the need to develop a standardized documentation system for severe contrast-induced reactions. Education regarding transfer of care and documentation should be emphasized during clinical simulation., (Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

In forensic pathology routine, fatal cases of contrast agent exposure can be occasionally encountered. In such situations, beyond the difficulties inherent in establishing the cause of death due to nonspecific or absent autopsy and histology findings as well as limited laboratory investigations, pathologists may face other problems in formulating exhaustive, complete reports, and conclusions that are scientifically accurate. Indeed, terminology concerning adverse drug reactions and allergy nomenclature is confusing. Some terms, still utilized in forensic and radiological reports, are outdated and should be avoided. Additionally, not all forensic pathologists master contrast material classification and pathogenesis of contrast agent reactions. We present a review of the literature covering allergic reactions to contrast material exposure in order to update used terminology, explain the pathophysiology, and list currently available laboratory investigations for diagnosis in the forensic setting.

Various side effects have been associated with the clinical use of contrast media. Immunological mechanisms have been proposed but there have been very few experimental studies with animal models. We have attempted to develop murine models to determine whether or not anaphylactic antibodies such as IgE and IgG1 against hapten (DNP) were enhanced with contrast medium (iopamidol) as an adjuvant or if the contrast medium itself produced antibodies of the IgE class. The results showed that anti-hapten IgE and IgG1 production was greatly enhanced with immunogen plus contrast medium. Anti-contrast medium antibodies of the IgE class could not be detected by PCA reactions. The enhancement of IgE and IgG1 production for hapten was associated with IL-4 release by the neutralization test used by monoclonal anti-IL-4 antibodies. This is the first observation to show that contrast media may have a strong adjuvant effect for the production of IgE and IgG1. This murine model demonstrates a possible immunological function of contrast media in vivo.

Objective: To review various pretreatment regimens for the prophylaxis of anaphylactoid reactions to radiographic contrast media (RCM) in high-risk patients. The proposed etiologies and risk factors for such reactions are also reviewed., Data Sources: A MEDLINE search of the English-language literature was used to identify pertinent human studies and reviews., Study Selection: All studies comparing pretreatment regimens for anaphylactoid reactions to RCM were reviewed as well as studies comparing the incidence of anaphylactoid reactions between lower and higher osmolar RCM., Data Synthesis: The two types of reactions to RCM are dose-independent, unpredictable anaphylactoid (pseudoallergic or idiosyncratic) reactions and the dose-dependent, predictable physicochemical (intrinsic, nonidiosyncratic) reactions. Prophylaxis of the former type is targeted at stemming the effects of certain chemical mediators, primarily histamine. The use of lower osmolar RCM is associated with a lower incidence of anaphylactoid reactions compared with higher osmolar RCM, but is significantly more expensive. Risk factors for such reactions are a history of previous anaphylactoid reaction to RCM, asthma, and reaction to skin allergens or penicillin. Discontinuation of any beta-blockers before the procedure is suggested. Pretesting patients with a small amount of RCM has little predictive value for an anaphylactoid reaction. Various pretreatment prophylactic regimens have been studied. Almost all included a corticosteroid to target the inflammatory response and a histamine1 (H1)-antagonist to blunt the effects of histamine. In some clinical trials, ephedrine was added for bronchodilation and cimetidine for its antagonism at the histamine2-receptor. The few controlled clinical trials that have been performed show the combination of prednisone and diphenhydramine to be most beneficial in preventing anaphylactoid reactions to RCM. The addition of ephedrine or cimetidine to a pretreatment regimen remains controversial., Conclusions: More controlled clinical studies comparing various pretreatment regimens for high-risk patients need to be performed, especially in patients receiving lower osmolar RCM. Recommendations for high-risk patients who must receive RCM include use of a lower osmolar agent, pretreatment with a corticosteroid and an H1-antagonist, discontinuation of beta-blockers if the patient is taking any, and bedside availability of appropriate medications and equipment to treat anaphylaxis.

Contrast media reactions may be classified as anaphylactoid, vasomotor, severe or life threatening, and fatal. Anaphylactoid reactions mimic immunoglobulin E-mediated hypersensitivity in that signs may consist of urticaria, angioedema, wheezing, dyspnea, hypotension, or shock. These reactions occur in 2% to 8% of all contrast media infusions. Vasomotor reactions occur in 5% to 8% of patients and consist of nausea, vomiting, flushing, and warmth. Severe reactions during which there is a concern for life occur about once per 1000 procedures. Fatalities have occurred in from 1:3000 procedures for intravenous cholangiography to between 1:10,000 to 1:100,000 procedures for intravenous urography. The pathogenesis of contrast media reactions is unknown, and various mechanisms may be associated with different clinical features. Radiocontrast media infusions can cause rises in plasma histamine and complement activation by either classic or alternate pathways or nonsequentially, yet adverse reactions may or may not occur. Abnormalities in the complement system or an increased conversion of prekallikrein to kallikrein has been demonstrated in some patients who have had anaphylactoid reactions. It is unknown if these mechanisms can explain the pathogenesis of anaphylactoid contrast media reactions. When patients who have had definite anaphylactoid reactions require a repeat procedure, the incidence of reactions ranges from 35% to 60% for intravascular infusion. Pretreatment with prednisone and diphenhydramine has been demonstrated to reduce this reaction rate to 9% in 465 procedures. Prednisone-diphenhydramine and ephedrine have further reduced the reaction rate to 3.1% in 192 procedures. These results are statistically significant (X2 = 5.4996, p = 0.019). Emergency equipment should be available should a severe reaction occur.(ABSTRACT TRUNCATED AT 250 WORDS)