The amount of bile draining out of the bile duct and the symptoms of discomfort can be used to determine whether there is a blockage or not. The first thing to do is to observe the amount of bile coming out of the drain. Under normal circumstances, the amount of bile coming out of the drain will gradually decrease due to the gradual recovery of the bile duct, and if the amount of bile coming out of the drain suddenly decreases, or if the flow speed suddenly slows down, or even if there is no flow of bile, it can be determined that the bile drain may be blocked. Secondly, if the bile drainage tube is blocked, the lack of bile can cause abdominal pain, yellow eyes or fever. A suspected bile drain blockage can also be determined by ultrasound and drain imaging. Any suspicion of a blocked bile drain should be reported to your doctor, who will determine whether there is a possibility of blockage based on your specific condition and proceed to the next step.