Why does bile leak around an indwelling biliary drain?
Biliary drains require considerable maintenance after they are placed, and the maintenance often adversely affects the quality of life of patients. Leakage occurs for various reasons. Standard biliary tubes consist of a catheter with side holes and a distal locking loop. For the tube to work properly, the side holes must be patent and properly positioned. The key to proper positioning is the proper location of the most peripheral side hole. This hole should be located just inside the biliary duct where access was obtained. If the most peripheral side hole of the catheter is malpositioned, leakage can occur. Migration or malposition of the tube so that the hole is outside of the duct and in the parenchymal tract results in bile leaking back along the catheter onto the skin. If the hole is too far in, the bile duct peripheral to the catheter may become obstructed and leak along the course of the catheter. Meticulous tube placement, a cholangiogram that confirms proper positioning, along with good technique in securing the catheter to the skin surface will help to prevent these problems. Another common cause of leakage is clogging of the side holes of the catheter with viscous bile or duct debris. This situation can be managed via catheter exchange with consideration given to upsizing the tube if the complication occurs frequently. As a general rule, long-term biliary drainage catheters are exchanged every 3 months for preventive maintenance.