Informed consent is obtained from the patient.
The patient is NPO the night prior to the procedure. An intravenous line is begun to ensure adequate hydration and to facilitate the administration of any sedatives during the procedure. Most physicians will administer a broad spectrum antibiotic intravenously before the procedure. After that time, the patient can be discharged if no untoward symptoms are reported. Any prior cholangiograms which demonstrate the calculi which are to be removed should be made available to the interventional radiologist beforehand.