SAGES Magazine

THE SOUTH AFRICAN GASTROENTEROLOGY REVIEW 2022 | VOLUME 20 | ISSUE 3 | 48 ERCP | A GUIDE FOR NURSES AND ASSISTANTS | Re-printed with permission two channels within them, one for injection of contrast and another for a wire to be passed through. A wide variety of instruments are designed to try and make cannulation easier, and as mentioned the ones I favour are the ones with a rounded or ‘DomeTip’ as shown here, but each operator has a system which works best for them, and that may mean familiarising yourself with different types of equipment which, after all, do pretty much the same thing. Preparation of the sphincterotome for use: Each brand of equipment is different, and it is worthwhile watching experienced assistants prepare the equipment for use before attempting it yourself. With COOK sphincterotomes, the protective metal wire is carefully taken out of the tip, taking care not to distort the natural shape of the device. A guide wire is passed from the handle end down the wire channel, until the tip is just short of protruding from the end. Contrast is injected into the correct channel until it comes out of the tip as well (‘priming’). Cannulation techniques: I will go through the following techniques: • Using the sphincterotome • Dual wire technique • Needle knife In my practice I will always use a sphincterotome with a pre-loaded wire as the first instrument in a ‘virgin’ ampulla. This is because the angle of the sphincterotome can be adjusted by putting tension on the cutting wire, and the wire can be advanced into the duct easily and locked in place when the duct is found. Contrast can be injected and a cut can be made through the sphincter (sphincterotomy - more later) all with the same instrument, which saves a lot of time. Sometimes I will advance the wire before the sphincterotome enters the ampulla (is ‘engaged’) directly into the bile duct. Some practitioners prefer to use a normal cannula and exchange it for a sphincterotome once cannulation has been achieved. The correct angle, pressure and direction must all be found for cannulation to be successful. All patients are different and it is impossible to judge accurately which will go well and 2 2