SAGES Magazine

THE SOUTH AFRICAN GASTROENTEROLOGY REVIEW 2022 | VOLUME 20 | ISSUE 3 | 53 ERCP | A GUIDE FOR NURSES AND ASSISTANTS | Re-printed with permission PA R T 4 : S T ON E S Gallstones can migrate from the gall bladder and settle in the CBD where they can cause pain, block the duct and cause jaundice, irritate the pancreatic duct and cause pancreatitis, or a combination of all three. Sometimes they are found by chance and in most cases the patient is advised to undergo ERCP to remove CBD stones to prevent problems in the future. To remove a stone from the CBD, the sphincter has to be cut as much as possible to allow the stones to pass through. Contrast is injected into the CBD to see how many and where the stones are, and an extraction balloon is placed above the stone, inflated and withdrawn, pulling the stone into the duodenum (known as ‘trawling’ the duct). The stones should be removed one by one (to prevent the lowest one blocking the passage of the higher ones), and when there have been at least two ‘clear trawls’, the operator will leave the balloon inflated at the bottom of the duct, inject more contrast and take an Xray picture to document a clear duct (an ‘occlusion cholangiogram’). The stones then pass through the gut and are digested - they are in fact quite soft and not sharp or stone-like in the majority of cases. Inflating and deflating the balloon is a skill that needs to be understood. Extraction balloons are inflated with a syringe of air, and locked with a rotating tap. When the tap is in line with the handle it is open, and when it is rotated 90 degrees across the handle then it is locked. The inflation syringes are attached with a Luer lock onto the catheter and are all slightly different. Some will have markings on them stating how much air needs to be inflated to reach a certain diameter on the balloon but these are only a rough guide and not very accurate. The diameter of the bile duct is estimated by comparing it to the endoscope on the Xray image which is usually 12mm in diameter. The tip of the balloon catheter is visible on the Xray images as two dark spots in the bile duct (usually just above the scope). Ask the operator where it is if you can’t spot it. The balloon should be inflated so the edges of the balloon touch the sides of the bile ducts (see the yellow arrow in the picture below). Any more than this and the bile ducts stretch (which is very painful) and any less, and the stone may slip along the side of the 2 7 Biliary/Pancreatic - Extraction Fusion® Extraction Balloon Used for endoscopic removal of stones in the biliary system and for contrast injection.