Coagulation function-an essential laboratory examination before operation

Coagulation function examination can know whether the patient has abnormal coagulation function before operation, effectively prevent intraoperative and postoperative bleeding and other accidents, so as to obtain the best surgical effect.

The hemostatic function of the body is completed by the interaction of platelets, coagulation system, fibrinolysis system and vascular endothelial system. In the past, we used bleeding time as a screening test for hemostasis function defects, but it has been replaced by coagulation function test because of its low standardization and poor sensitivity, which can not reflect the content and activity of coagulation factors. Coagulation function examination mainly includes plasma prothrombin time (PT), PT activity, international standardized ratio (INR), fibrinogen (FIB), activated partial thromboplastin time (APTT) and plasma thrombin time (TT) calculated from PT.

PT mainly reflects the function of exogenous coagulation system. Prolongation of PT is mainly seen in the decrease of congenital coagulation factors Ⅱ, ⅴ, ⅶ and ⅹ, and the deficiency of fibrinogen and acquired coagulation factors (DIC, primary fibrinolysis, obstructive jaundice, vitamin K deficiency and increase of anticoagulant in blood circulation). PT shortening is mainly seen in congenital coagulation factor V elevation, early DIC, thrombotic diseases, oral contraceptives and so on. Monitoring PT can be used as a clinical monitoring index of oral anticoagulants.

APTT is the most reliable screening test for endogenous coagulation factor deficiency. APTT prolongation is mainly seen in hemophilia, DIC, liver disease, massive transfusion of stored blood, etc. APTT shortening is mainly seen in DIC, prethrombotic state and thrombotic diseases; APTT can be used as a monitoring index of heparin therapy.

TT prolongation is seen in low or no fibrinogen and abnormal fibrinogen, increased FDP in blood (DIC), and heparin and heparin-like substances in blood (such as heparin therapy, SLE, liver disease, etc.). ).

There was an emergency patient who was suspected to have DIC because of the prolongation of PT and APTT in preoperative laboratory examination. At the suggestion of the laboratory, the patient received a series of DIC tests, and the results were positive, but the patient did not show obvious DIC symptoms. If the patient does not have a blood coagulation test and operates directly, the consequences will be unimaginable. Many such problems can be found from the examination of coagulation function, which has won more time for clinical timely detection and treatment of diseases. Coagulation series test is an important laboratory examination of patients' coagulation function, which can find abnormal coagulation function before operation and should be paid enough attention to.