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

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.