This document discusses coagulation and tests used to evaluate hemostasis and bleeding disorders. It covers the stages of hemostasis, factors involved in coagulation, tests for platelet count, bleeding time, prothrombin time, activated partial thromboplastin time, fibrinogen, and coagulation factor assays. An approach to evaluating a patient with abnormal bleeding is also outlined.

1. COAGULATION PROFILE
DR SHIVAPRASAD SHARMA THANUGULA
FINAL YEAR PGSCHOLAR
DEP OF KAYACHIKITSA
KAHER’S SHRI BMK AYURVEDA MAHAVIDYALAYA
BELAGAVI

2. HAEMOSTASIS
• Arrest or stoppage of bleeding
STAGES OF HAEMOSTASIS
1. Vasoconstriction
2. Platelet plug formation
3. Coagulation of blood

3. COAGULATION OF BLOOD
• Defined as the process in which blood loses its
fluidity and becomes a jelly like mass few
minutes after it is shed

4. FACTORS IN COAGULATION
• I Fibrinogen
• II Prothrombin
• III Tissue factor or thromboplastin
• IV Calcium
• V Proaccelerin (Labile factor)
• VII Proconvertin (Stable factor)
• VIII Antihaemophilic factor A,
Antihaemophilic globulin

5. • IX Antihaemophilic factor B,
Plasma thromboplastin component,
Christmas factor
• X Stuart-Prower factor
• XI Plasma thromboplastin antecedent,
• XII Hageman factor
• XIII Fibrin stabilising factor,
Laki-Lorand factor

6. STAGES OF BLOOD CLOTTING
• STAGE 1.
Formation of prothrombin activator
1. Intrinsic pathway
2. Extrinsic pathway

8. • SATGE 2
Conversion of prothrombin to thrombin
STAGE 3
Conversion of fibrinogen to fibrin

9. INVESTIGATION OF
HAEMOSTATIC FUNCTION
TESTS FOR
1. Disordered vascular haemostasis
2. Platelet and their functions
3. Blood coagulation
4. Fibrinolysis
5. Coagulation inhibitors

10. BLEEDING TIME
• Based on the principle of formation of
haemostatic plug.
• Factors affecting the test are capillary function,
platelet number and the ability to form
aggregates.
• It involves cutting the underside of the subject's
forearm, in an area where there is no hair or
visible veins. The cut is of a standardized width
and depth, and is done quickly by an automatic
device.
• NORMAL RANGE 3-8 minutes.

11. Diseases that cause prolonged bleeding time
include
• thrombocytopenia
• disseminated intravascular coagulation (DIC)
• Bernard-Soulier disease
• Glanzmann's thrombasthenia
• von Willebrand’s disease
However bleeding time is normal in Haemophilia
Drugs that affect BT are Aspirin and COX
inhibitors.

12. PLATELET COUNT
• Screening test for assessing platelet function
• Methods
1. Peripheral blood platelet count using anayser.
2. Skin bleeding time
3. Examination of fresh blood film to see
morphologic abnormalities of platelets in a
Leishman stained peripheral bood smear.
Normal 1.5 – 4.5 lakh

13. CLOTTING TIME
• Clotting time is the time required for a sample
of blood to coagulate in vitro under standard
conditions
• There are various methods for determining
the clotting time, the most common being
the capillary tube method.
• NORMAL RANGE - 4-9 minutes at 37 C
• It is affected by heparin and warfarin
• It is delayed in clotting disorders like
Haemophilias

14. PROTHROMBIN TIME
• PT measures the factors involved in the extrinsic pathway
and in the common pathway. i.e I, II, V, VII, X.
• In this test, tissue thromboplastin (brain extract) and
calcium is added to determine PT.
• NORMAL RANGE- 10-14 seconds
• Causes of prolonged PT are
1. Oral anticoagulants
2. Liver disease
3. Vit K deficiency
4. DIC
5. lack of intestinal colonization by bacteria (such as
in newborns

15. ACTIVATED PARTIAL
THROMBOPLASTIN TIME
• kaolin-cephalin clotting time.
• This test is used to measure the intrinsic system factors
and factors common to both intrinsic and extrinsic
pathways. i.e. VIII, IX, XI, XII, X, V, prothrombin and
fibrinogen.
• NORMAL RANGE 30-40 seconds.
• It consists of addition of calcium, phospholipid and
kaolin.
• Apart from detecting abnormalities in blood
clotting, partial thromboplastin time is also used to
monitor the treatment effects with heparin, a widely
prescribed drug that reduces blood's tendency to clot.

16. • It is prolonged in
1. Parenteral administration of heparin
2. DIC
3. Liver disease
4. Circulating anticoagulants
5. Hemophilia

17. MEASUREMENT OF FIBRINOGEN
• The screening test for the measurement of
fibrinogen deficiency are
1. Thrombin time- (normal is under 20 seconds)
2. Fibrinogen titre in plasma dilution upto 32 is
considered normal.
• Higher values of both the tests are seen in
1. DIC
2. Raised concentration of FDP
3. Presence of heparin

18. SPECIAL TESTS
1. COAGULATION FACTOR ASSAYS
• Based on the results of PT and APTT
• They employ the use of substrate plasma that contain
all other coagulation factors except the one to be
measured.
• The unknown level of factor activity is compared with
standard control plasma with a known level of activity.
2. QUANTITATIVE ASSAYS
• Coagulation factors can be quantitatively assessed by
immunological and other chemical methods.

19. • The degree of correction of the clotting
time when plasma is added to clotting
system specifically deficient in the clotting
factor to be measured allows the level of
that clotting factor to be determined. E.g .
A factor VIII deficient plasma is used to
assay the level of factor VIII.

20. APPROACH TO A PATIENT WITH
ABNORMAL BLEEDING
TENDENCY• Full history
• Age, sex
• Present episodes of bleeding
• Frequency and duration
• Apparent cause
• Coexisting known bleeding disease
• Other diseases
• Drugs- aspirin, cox inhibitors, warfarin,
phenedione, salicylates
• Occupation
• Diet with ascorbic acid

21. • Past history– recurrent boleeding, age at
first episode of bleeding
• Haemorrhagic incidents--- ecchymosis,
petechiae, epistaxis, wound bleed
• Melaena, haematemesis, haematuria,
haemoptysis.
• Menstrual and post partum history
• Bleeding after trauma and surgery
• Therapeutic measures and response
• Family history

22. EXAMINATION
• General appearance
• Skin
• Mouth
• Wounds
• Abdomen
• Pelvis
• CNS
• Joints
• Urine

23. • ESSENTIAL INVSTIGATIONS IN A CASES
1. Full bood examination
2. Hb
3. Red cell morphology
4. WBC count
5. Patelet count
6. Peripheral smear
7. Skin bleeding time
FURTHER INVESTIGATIONS
1. Screening tests for blood coagulation- PT, aPTT,
factor assays
2. Test for platelet function for adhesion, aggregation

24. SUMMARY

25. THANK YOU……

26. Disorders of hemostasis
• Thromboembolic –undesirable clot formation
• Bleeding diseases –abnormalities that prevent
nornal clot formation
• Disseminated intravascular coagulation –
involves both type

27. Factors preventing undesirable
clotting
• Smooth endothelium of blood vessels prevents
platelets from clinging.
• Antithrombic substances nitric oxide and
prostacyclin secreted by endothelial cell.
• Vitamin E quinone acts as a potent
anticoagulant