Normal bleeding time is 1 -6 min by Duke method. Materials same materials used in Duke's method. Its chief application is in monitoring anticoagulant therapy. What is the Significance of the Clotting Time Blood Test Result? The mass is referred as clot and the phenomenon as coagulation. Stop timer as soon as fibrin strands are seen bridging the 2 broken ends of the tube.
Wipe off the first drop of blood 4. The time required for complete stopping of blood flow from the punctured blood vessels called the bleeding time. Less sensitive and now less often used than the activated time. Aim: The aim of the experiment is to determine the clotting time of the subject. Whole blood, when removed from the vascular system and exposed to a foreign surface, will form a solid clot.
Whole blood clotting time Lee-White Procedure, Materials and Normal value Clotting Time Procedure, Materials and Normal value B. Clotting time: It is time taken by the clotting factors of the blood to start haemostasis and the production of a proteinous web of fibrin thread to from a fibrin clot. This is repeated every 15 seconds, each time using a fresh portion of the filter paper, till bleeding stops. Bleeding Time Normal Values and Diseases B. Calculate the clotting time by average of 3 tube. Bleeding Time Procedures and Materials Used C. Remove the surgicutt immediately after triggering 10.
Stop the time as soon as the bleeding stops. Take the stain of the punctured point on a filter paper on 30 second and keep taking stain of blood in 20 second intervals until the bleeding stops. This prevents tissue thromboplastin from entering the blood sample. Diseases Bleeding Time Normal Values and Diseases Bleeding Time Procedures and Materials Used B. Whole blood coagulation time Clotting Time Tests of Haemostasis I. Under sterile conditions make a deep prick on the forearm just below the elbow. Requirements: Fine capillary glass tubes of about 10 mm length, cotton, rectified spirit, lancet, stop watch.
Puncture to a depth of 3mm with a sterile disposable lancet 3. Release the pressure of the sphygmomanometer. The tubes should be previously warmed to 37ºC and obviously should not contain anticoagulant. Blood is absorbed by filter paper till bleeding stops. Then the tube is kept undisturbed horizontally for about 1-2 minutes. Procedures and Materials Used Procedure, Materials used and normal value D. Each factor activates the next in a stepwise fashion.
All tubes are placed into the 37C water bath. Vascular defects - Senile purpura Henoch Schonlein purpura Platelets are important in preventing small vessel bleeding by causing vaso constriction and platelet plug formation. As they disintegrate they release serotonin and thromboplastin. Fill up at least 2 plain capillary tubes. Start the timer as soon as the 2nd drop of blood appears. Normal Values Diseases related Bleeding Time an invivo measurement of platelet participation in small vessel hemostasis.
Cleanse the test area with the 70% alcohol and let it dry. The following DoveMed website links are useful resources for additional information: Please visit our Laboratory Procedures Center for more physician-approved health information: References and Information sources used for the Article: Chang, V. Prothrombin time is typically analyzed by a laboratory technologist on an automated instrument at 37 °C as a nominal approximation of normal human body temperature. Our mission is to provide an online platform to help students to share notes in Biology. Brock biology of microorganisms 13th ed. Secondary - Thrombocytopenic purpura 2. Puncture to a depth of 3mm 3.
Slide method or drop method b. Normally it is 1-3 minutes for a normal human's blood. This simple test has been used to diagnose hemophilia, but it does not detect mild coagulation disorders. Blood is drawn into a test tube containing liquid sodium citrate, which acts as an anticoagulant by binding the calcium in a sample. Disadvantages: i Method is insensitive.
When the thread appears the stop watch is stoped. Clotting time is defined as the time interval in between onset of bleeding and appearance of semisolid mass i. As a result, no fibrinogen bridging of platelets to other platelets can occur, and the bleeding time is significantly prolonged. The recalcification time is found prolonged in most congenital and acquired coagulopathies, in the presence of endogenous inhibitors, and under heparin treatment. Clinical Application of Clotting Time : Clotting time is prolonged in following conditions: i Sever deficiency of coagulation factors. Needed in the conversion of prothrombin to thrombin but only in the extrinsic system.