The color of the laparoscopic drainage tube depends mainly on the purpose for which it was placed. If a laparoscopic drain is placed after a routine laparotomy, the fluid drained from the drain is usually light red in the early 1-2 days after the operation, and will directly change to light yellow after 3-4 days after the operation, and the flow of drainage in the drain will gradually decrease, and can be removed about 5 days after the operation. If the drainage tube is placed due to abdominal abscess, which is to fully drain the pus and at the same time can be flushed, the color in the drainage tube is mostly similar to the color of pus, i.e. yellow and has a fishy odor. And as the abscess pus subsides, the color will gradually become lighter and the fishy smell will also be reduced. Therefore, the purpose of placing abdominal drains is to observe the changes in the abdominal cavity on the one hand, and to adequately drain the abdominal cavity to draw out the pus and other substances, as well as to flush the wound. The different colors of the drains have a lot to do with the purpose of placing them.