After percutaneous nephrolithotomy, two fistula tubes are usually placed, i.e., the internal fistula tube and the external fistula tube. The external fistula is usually removed about one week after surgery, and the internal fistula is usually removed about one month after surgery. Percutaneous nephrolithotomy is mainly used for the treatment of kidney stones. After the operation, a fistula tube needs to be inserted in order to observe whether there is bleeding or stones left in the internal organs, and if there is bleeding or stones left, they can be drained through the fistula tube. The external fistula is located in the back of the waist. 5-7 days after the operation, drainage can be done through this fistula tube. If the drainage is smooth, the external fistula tube can be closed and observed for one day, and then removed if there is no abnormality. The internal fistula is located near the ureter, if there is still a small piece of stone left after the operation, the stone can be discharged out of the body through the urine through this fistula. The fistula can be kept in the body for about 1 month, and can be removed by itself if it is drained cleanly. However, if there is still a stone remaining after 1 month, the fistula should be replaced in time to prevent infection and other uncomfortable reactions. After percutaneous nephrolithotomy, we should take good care of the fistula, keep the skin near the fistula clean to avoid infection, and then remove the fistula when there is no bleeding or stones left in the body.