APTT medically refers to the activated partial thromboplastin time, which refers to the activity of coagulation factors in the endogenous coagulation pathway, and is an indicator used clinically to reflect coagulation function. Blood clotting is the process of coagulation factors involved in protein hydrolysis, and the time of prothrombin can reflect whether the body’s autologous blood coagulation function is normal, APTT normal range is usually in the 23-37 seconds. In addition, clinical use is also commonly used to observe the anticoagulant treatment of heparin. an extended APTT value of more than 10 seconds has detectable significance, and high values are common in acquired, congenital coagulation factor deficiency, such as hemophilia, systemic lupus erythematosus, as well as hepatobiliary disease, neonatal bleeding disorder, obstructive jaundice, or the application of anticoagulant drugs, such as heparin, warfarin, can also appear this result. In contrast, a low APTT value indicates that the body is in a hypercoagulable state and can be seen in abnormal fibrinogenemia, thrombotic disorders such as myocardial infarction, cerebrovascular lesions, deep vein thrombosis, and nephrotic syndrome and hypertensive syndrome of pregnancy. Therefore, the APTT test is often used as an aid in the diagnosis of disease and in the determination of drug efficacy, and can be chosen under the guidance of a physician. In addition, the test is mainly extracted from human plasma for testing, and the blood specimen can be gently shaken 3-5 times after collection to mix with the anticoagulant to avoid blood clotting, while avoiding violent shaking of the specimen to avoid hemolysis, which can affect the test results.