What Is Bleeding Time?

Under certain conditions, the time required for the natural bleeding from blood to natural stop after artificially puncturing skin capillaries is measured, which is called bleeding time (BT) measurement. The BT measurement is affected by the number and quality of platelets, the structure and function of capillaries, and the interaction between platelets and capillaries, but is less affected by blood coagulation factor content and activity. The traditional measurement methods of BT include Duke method and Ivy method. Currently, the standardized bleeding time (TBT) method recommended by the World Health Organization (WHO) is commonly used.

Under certain conditions, the time required for the natural bleeding from blood to natural stop after artificially puncturing skin capillaries is measured, which is called bleeding time (BT) measurement. The BT measurement is affected by the number and quality of platelets, the structure and function of capillaries, and the interaction between platelets and capillaries, but is less affected by blood coagulation factor content and activity. The traditional measurement methods of BT include Duke method and Ivy method. Currently, the standardized bleeding time (TBT) method recommended by the World Health Organization (WHO) is commonly used.

Name

Bleeding time

category

blood

Reference interval

TBT method: 6.9 ± 2.1min.

Clinical significance of bleeding time

(1) BT prolongation: seen in: abnormal platelet counts, such as various thrombocytopenia; platelet quality defects, such as congenital and acquired platelet disease, platelet weakness; etc. lack of certain coagulation factors, such as vascular blood Friend disease (vWD), hypofibrinogenemia and disseminated intravascular coagulation (DIC), etc .; vascular diseases, such as hereditary hemorrhagic capillaries. Drug effects, such as taking pansentin, acetylsalicylic acid, etc.
(2) BT shortening is seen in some severe prethrombotic states and thrombotic diseases.

Bleeding time considerations

(1) Antiplatelet drugs such as aspirin, acridide, clopidogrel, etc. should be stopped one week before the test. Unsuitable: People with coagulopathy, such as hemophilia.

(2) The influencing factors of BT measurement are: skin incision depth (the most important factor), length, position, direction, pressure on capillaries; skin temperature, etc. For children, the elderly, and patients with a history of scarring, the TBT can be used instead of TBT for blood time measurement.

(3) BT measurement: keep warm, especially in winter, otherwise it will affect the results.

(4) Because BT measurement has many influencing factors, BT measurement is rarely used internationally. Its detection function has been mainly platelet count, platelet function test, and prothrombin time (PT) and activated partial coagulation for screening coagulation Replaced by live enzyme time (APTT) measurement.