Mechanism of haemostasis , fibrinolysis and method to control haemorrhage by Dr Bipul Borthakur

1. MECHANISM OF HAEMOSTASIS ,
FIBRINOLYSIS AND METHOD TO
CONTROL HAEMORRHAGE
DR. BIPUL BORTHAKUR
PROFESSOR AND HOD ,
DEPARTMENT OF ORTHOPAEDICS, SMCH

2. HAEMOSTASIS
• Means prevention of blood loss.
• Definition:- spontaneous arrest or stoppage of
bleeding from injured blood vessel by
physiological process.
• Is precisely orchestrated process involving
platelets, clotting factors, and endothelium that
occurs at the site of vascular injury and
culminates in the formation of a blood clot, which
serves to prevent or limit the extent of bleeding.

3. Function of haemostasis :-
maintain blood in fluid state
 arrest bleeding following trauma
 removes platelet plug when healing is complete
THREE PROCESS :-
 I) vasoconstriction
 II) formation of temporary haemostatic plug
 III) formation of definitive haemostatic plug

5. I) VASOCONSTRICTION:-
 IMMEDIATE:- direct effect of injury
 LATE :- by release of 5HT by bound platelets to
the collagen
II) FORMATION OF TEMPORARY HEMOSTATIC
PLUG:-

6. PROCESS :- (a) platelet adhesion
(b) platelet activation
(c) platelet aggregation
(d) temporary haemostatic plug
(A)PLATELET ADHESION:-
• done by VWF
• degranulation of platelet occurs
• Helped by fibronectin and other components of
extra cellular matrix.
• Calcium is required

7. (B) PLATELET ACTIVATION :-
• Platelet secretsADPs & thromboxane
A2activate other platelets and cycle continues
(C) PLATELET AGGREGATION :-
• activate platelet becomes sticky and stuck to
other and aggregates to form platelet plug.
• Platelet activating factors released by neutrophils,
monocytes and platelets cell membrane lipids
also increases the process

8. • (D) FORMATION OF TEMPORARY
HAEMOSTATIC PLUG:-
Platelet adhesion  platelet aggregation 
platelet plug formation

10. FORMATION OF DEFINITIVE
HAEMOSTATIC PLUG
• Temporary haemostatic plug converts into
definitive haemostatic plug by blood
coagulation
BLOOD COAGULATION:-
• When a vessel is ruptured , procoagulants
from the area of tissue damage become
activated clot formation occurs

11. • CLOTTING TAKES PLACE IN THREE STEPS:-
• 1st STEP:-
rupture/damage of blood vessels
complex cascade of chemical reactions occur 
prothrombin activator
• 2nd STEP:-
Prothrombin is converted into thrombin by
prothrombin activator.
Prothombin is formed by the liver .
Vitamin k required by the liver for normal
activation of prothrombin

13. 3rd STEP:-
fibrinogen converted to fibrin by thrombin.
Thrombin acts on fibrinogen to remove four low
molecular weight peptides from each molecule of
fibrinogen forming one molecule of fibrin
monomer.
Fibrin monomer polymerise to form reticulum of
blood clot

14. • FORMATION OF PROTHROMBIN ACTIVATOR :-
Prothrombin considered to be formed in two
ways.
1> Extrinsic pathway :- begins with trauma to
vascular wall and surrounding tissues
2> Intrinsic pathway:- begins in the blood

15. • STEPS OF EXTRINSIC PATHWAY:-
1> Release of tissue factor :- traumatised tissue
releases tissue factor.
2> Activation of factor X :- tissue factor
activates factor VII into VIIa, which along with
ca+2 activates factor X.
3> Effects of Xa to form prothrombin activator:-
Xa combines with tissue factor & factor V to
form complex called prothrombin activator.

16. EXTRINSIC PATHWAY

17. STEPS OF INTRINSIC PATHWAY
• 1) blood trauma causes activation of factor XII
and release of platelet phospholipids
• 2) activation of factor XI by activated factor XII
• 3) activation of factor IX by activated factor XI
• 4) activation of factor X

18. INTRINSIC PATHWAY

20. FIBRINOLYSIS
• It is a process by which blood clot is prevented
from growing and becoming pathological.
• Prevents excessive fibrin deposition
• It is a physiological process.
• Can be dangerous if it were to expand beyond
boundary.
• Prevents clot formation but doesnot destroys
the clot

21. • This process requires a substance called
plasmin or fibrinolysin, which breaks down
fibrin and interferes with its polymerization.
• Clot stimulates tissue plasmin activator
• Plasminogen is found in blood in inactivated
state by tissue plasminogen activator.

24. METHODS TO CONTROL
HAEMORRHAGE
• HAEMORRHAGE :- Extravasation of blood from
vessels, is most often the result of damage to blood
vessels or defective clot formation.
• CLASSIFICATION
• ACCORDING TO SOURCE OF BLEEDING
• CAPILLARY :- BLEEDING IS RAPID, BRIGHT RED COLOR
• VENOUS :- STEADY FLOW, DARK RED COLOR
• ARTERIAL :- SPURTING BLOOD, PULSATING FLOW , BRIGHT
RED COLOR

25. BASED ON TYPES OF HAEMORRHAGE :-
• REVEALED HAEMORRHAGE:-
 EXTERNAL HAEMORRHAGE
 RESULTS FROM SOFT TISSUE INJURY
• CONCEALED HAEMORRHAGE:-
 INTERNAL HAEMORRHAGE
 RESULTS FROM BLUNT OR PENETRATING TRAUMA
 MORE DANGEROUS THAN REVEALED HAEMORRHAGE
• INITIALY CONCEALED BUT LATER REVEALED:-
 EXAMPLE – HEMATURIA, HAEMATEMESIS, MELAENA

26. ON THE BASIS OF TIME:-
• PRIMARY:- at the time of trauma
• REACTIONARY:- within 24 hours of trauma/surgery
• SECONARY:- within 7 to 14 days of trauma/surgery
ON THE BASIS OF VOLUME OF BLOOD LOSS:-
• MILD:- blood loss <500ml
• MODERATE:- blood loss 500ml -1L
• SEVERE:- blood loss > 1L

27. ON THE BASIS OF PERCENTAGE OF BLOOD LOSS
• CLASS I :- upto 15%
• CLASS II :- upto 15 -30%
• CLASS III :- upto 30-40 %
• CLASS IV :- more than 40%

28. • HAEMORRHAGE ASSESSMENT:-
FRACTURE BLOOD LOSS
-> PELVIS 2L
-> FEMUR 1.5 L
-> TIBIA/FIBULA 500ml -750ml

29. METHODS OF ACHIEVING
HAEMOSTASIS
1. MECHANICAL :-
(A) PRESSURE :-
 immediate measure for capillary or venous bleeding
 this would control most haemorrhage
 PRESSURE POINTS :-
.Temporal artery for scalp
.Carotid artery for neck
.Brachial artery for upper limb
.Femoral artery for lower limb
(B) HAEMOSTAT:- directly occlude bleeding vessels

30. (C) SUTURES AND LIGATION :- severed blood vessels may be tied
with ligatures
(D) CLIPS
(E) ELEVATION
(f) SPLINTING
(G) TOURNIQUETS

31. 2. CHEMICAL METHODS :
• ADRENALINE
• THROMBIN
• SURGICEL
• GELATIN SPONGE
• NATURAL COLLAGEN SPONGE

32. 3. THERMAL AGENTS :-
• CAUTERY
• ELECTROCAUTERY
• LASERS
• CRYOSURGERY

33. 4. SUPPORTIVE MEASURES :-
• I.V. fluids
• whole blood transfusion
• fresh frozen plasma
• cryoprecipitates

34. 5. SPECIAL MEASURES :-
• ANTI SHOCK GARMENTS –
pneumatic and non pneumatic

35. THANKYOU.