Coagulation of Blood

When the blood is shed or drawn from a vein , it looses its fluidity in a few minutes and sets into semi solid jelly like mass . The phenomenon is called ‘coagulation ‘ or clotting of blood . In a test tube , if the blood is collected , it is observed that after coagulation . The clot refracts to a smaller volume and  serum will separate . The serum will smaller not clot any more . In the formation of clot , R.B.C and W.B.C have no role but platelets take some important part in the process of coagulation . Under ultra microscope if the process of coagulation is observed , it is seen that there will be formation of minute granules , often near a clump of disintegrating  platelets . These minute granules will unite to form needles . These needles will again unite and form long thread and form net-work . In the net-work , R.B.C  and W.B.C will be enlarged and the serum separate out .

Factors responsible for Blood coagulation …..

1.       Factor I                    -           Fibrinogen

2.      Factor II                   -           Prothrombin

3.      Factor III                  -           Thromboplastin

4.      Factor IV                  -           Calcium

5.      Factor V                   -           Labile factor ( pro-acetarin , plasma ac-globin )

6.      Factor VI                  -           Accelerin

7.      Factor VII                -           Proconvertin

8.      Factor VIII               -           Anti-haemophilic globulin ( AHG )

9.      factor IX                   -           Plasma thromboplastin component

10.  Factor X                   -           Stuart power factor

11.  Factor XI                  -           Plasma thromboplastin antecedent ( PTA )

12.  Factor XII                -           Hageman factor ( HF )

13.  FactorXIII                -           Fibrin stabilizing factor