The causes of bile duct puncture drainage suddenly stop flowing are drainage tube dislodgement, drainage tube blockage, bile duct obstruction and so on. 1. Drainage tube dislodgement: During the puncture operation, the drainage tube is not placed in the correct position, resulting in bile not flowing out of the drainage tube; the drainage tube is not properly fixed during the puncture operation or is moved after the operation, resulting in the drainage tube dislodging from the original bile duct, leading to the drainage tube suddenly not flowing. 2. Drainage tube obstruction: In some cases, a stone falling into the drainage tube can lead to obstruction of the drainage tube, which in turn leads to a break in the flow of the drainage tube. In addition, the drainage tube can also be blocked if it is folded or knotted after the operation. 3. Biliary tract obstruction: the biliary tract of human body is obstructed due to falling stones or enlarged tumors, which leads to poor drainage. For patients whose drainage tube suddenly stops flowing after choledochotomy, they should go to the relevant departments of regular hospitals as soon as possible to find out the causes and carry out targeted treatment, so as to avoid delaying the condition and leading to the occurrence of adverse results.