According to the standards established by the International Association of Pancreatic Diseases, pancreatic leakage is divided into four grades. Among them, secondary and tertiary are two common types. Among these grades, amylase level is one of the important indexes, which is used to evaluate whether patients have obvious pancreatic abscess or other complications. When the amylase content in the drainage fluid is more than 3 times but not more than 1 times the normal value, it is considered as secondary pancreatic leakage; When the detection result is more than 1 times, it is classified as grade III and IV thoracic leakage.