Reactions to Contrast Media (CM) Administered at the Time of the Endoscopic Retrograde Cholangiopancreatography (ERCP)

Study Overview
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Brief Summary
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The aim of this study is to prospectively document the incidence of CM adverse reactions at the time of ERCP and to determine whether various perceived risk factors are predictive of adverse reaction. Adverse reactions to iodine containing contrast media (CM) have been described after endoscopic retrograde cholangiopancreaticography (ERCP) but have been difficult to study due to their extremely low incidence. Adverse reactions can be classified by severity (mild, moderate or severe) or underlying mechanism (idiosyncratic versus nonidiosyncratic). Nonidiosyncratic reactions are related to the dose and osmolality of the CM; these are not observed during ERCP due to the relative small amount of systemic absorption of CM. Idiosyncratic reactions on the other hand are not dose-dependent and generally occur shortly after administration of CM. Premedication with corticosteroids, H1/H2 -blockers and the use of low osmolality CM is beneficial in preventing nonidiosyncratic reactions during intravascular administration. However their role in during ERCP is unclear as CM is not injected into the intravascular space. Currently there are no formal recommendations and clinical practice varies considerably. The general purpose of this study is to determine the incidence of CM reactions during ERCP and to determine whether various risk factors are predictive of idiosyncratic reactions. Based on these results, we hope to develop guidelines for the use of prophylaxis to prevent CM reactions in ERCP.

Official Title
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Reactions to Contrast Media (CM) Administered at the Time of Endoscopic Retrograde Cholangiopancreatography (ERCP)

Conditions
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Contrast Allergies

Intervention / Treatment
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* Procedure: ERCP as medically indicated by subjects referring physician


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 years or older. Scheduled to undergo ERCP at the University of Florida, Gainesville, FL History of prior reaction to IV CM and/or shellfish allergy Subject must be able to give informed consent Exclusion Criteria: Any contraindication to performing ERCP. Participation in another research protocol that could interfere or influence the outcomes measures of the present study. The subject is unable/unwilling to give informed consent.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| ERCP group<br>All patients who have been scheduled for an ERCP due to medical necessity will be considered for this study. | Procedure: ERCP as medically indicated by subjects referring physician<br>* Determine the incidence of adverse reactions to CM administered during ERCP in patients with prior reaction to IV CM administration and/or shellfish allergy.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determine the incidence of adverse reactions to CM administered during ERCP in patients with prior reaction to IV CM administration and/or shellfish allergy. |  | at the time of the subjects ERCP |