This presentation will help you to understand the physiology of blood coagulation and various factors involved in it.

2. Contents
Haemostasis
Vascular Phase
Platelet Phase
Clot formation
Clot retraction
Fibrinolysis
Bleeding Disorders
Diagnosis of bleeding disorders
Clinical implication in periodontology

3. Haemostasis

4. Haima + Stasis
Prevent blood
loss

5. Maintains blood flow
Prevents bleeding

7. • Stages of Hemostasis

9. Vascular Phase

12. PLATELET Phase

13. Platelets
• Thrombocyte = “ thrombos” + “ Kytos”
•1,50,000 to 400,000 per cu mm
Lifespan is 9 – 12 days

14. • Membrane
• Outer glycocalyx layer—
glycoproteins
• Inner lipoprotein layer—
phospholipid

15. Platelet PLUG

20. Blood coagulation

25. Role of thrombin

26. Fibrin formation

27. SEM of clot

28. • Release of fibrin stabilizing factor
• Contractile protein of platelets
• Activated and accelerated by thrombin
and Ca ions.

31. ROLE OF ENDOTHILIUM

37. Approach to the diagnosis of bleeding
disorder
Clinical Evaluation
History
Physical Examination
Family history
Laboratory Evaluation
Screening test
Specific test

39. Clinical Features of Bleeding Disorders
Platelet disorders Coagulation
disorders
Site of bleeding Skin Deep in soft
tissues
(epistaxis, gum, Mucous
vaginal, GI tract) membranes,
joints, muscles)
Petechiae Yes No
Ecchymoses (“bruises”) Small, superficial Large, deep
Hemarthrosis / muscle bleeding Extremely rare Common
Bleeding after cuts & scratches Yes No
Bleeding after surgery or trauma Immediate, Delayed (1-2
days),
usually mild often severe

40. Platelet Coagulation
Petechiae, Purpura Hematoma, Joint bl.

42. Tests for Primary Hemostasis
• Bleeding time platelet & vascular phases
• PFA – 100 system Platelet function
• Platelet count Quantification of platelets
• Blood smear Quantitative & morphological
abnormalities of platelets ,
Detection of underlying
haemotological disorder

43. Tests for Secondary hemostasis
• Clotting factor Crude test of coagulation phase
• Prothrombin factor Extrensic & common pathway
• Activated partial
thromboplastin time Intrensic & common pathway

44. PLATELET COUNT
 NORMAL 150,000 - 400,000 CELLS/MM3
< 100,000 Thrombocytopenia
50,000 - 100,000 Mild Thrombocytopenia
< 50,000 Sev Thrombocytopenia

45. BLEEDING TIME
 PROVIDES ASSESSMENT OF PLATELET COUNT
AND FUNCTION
NORMAL VALUE
2-8 MINUTES

47. PROTHROMBIN TIME
 Measures Effectiveness of the Extrinsic Pathway
 Measures the activity of V, VII, X, II , I
NORMAL VALUE
11-16 SECS

48. Prothrombin time prolongs..
Extrinsic pathway factor deficiencies
(FII, V, VII, X)
– Inherited or acquired
– Consumption (DIC)
– oral anticoagulant therapy

49. INR
INR: International normalized ratio
-was established by the WHO and the International Committee on Thrombosis
and Hemostasis for reporting the results of prothrombin tests
-All PT results are standardized by this calculation:
INR= ( Patient PT / Control PT) ISI
ISI= International sensitivity index
- Given by the manufacturer for each particular thromboplastin reagent and
instrument combination

51. ACTIVATED THROMBOPLASTIN
TIME
 Measures Effectiveness of the Intrinsic
Pathway & common pathway
NORMAL VALUE
25-40 SECS

52. APTT prolongs..
1. Intrinsic pathway factor deficiencies
(FXII, XI,VIII, IX, HMWK, prekallikrein )
- Inherited or acquired
- Consumption (DIC)
- PIVKA factors in cumarin therapy
2. Specific inhibitors against FXII, XI, VIII, IX, HMWK, prekallikrein
3. Lupus anticoagulant
4. Non-fractionated heparin therapy

53. THROMBIN TIME
 Time for Thrombin To Convert
Fibrinogen Fibrin
 A Measure of Fibrinolytic Pathway
NORMAL VALUE
9-13 SECS

54. TT Prolongs..
1. Hypo- afibrinogenaemia
2. Dysfibrinogenaemia
3. Non fractionated heparin
4. Fibrinogen/ fibrin degradation product s
5. Chronic liver disease

55. SPECIFIC TESTS
Tests for specific Platelet Functions
1. Platelet aggregration test
2. Flow cytometry
3. Test for platelet secretion
4. Clot retraction test
5. Platelet procoagulant activity
Test for Coagulation Phase
1. Quantitative estimation of Fibrinogen
2. Coagulation factor assays
3. F XIII Qualitative assay
Latex agglutination test for Fibrinolysis

56. Bleeding
Disorders
Inherited
• Vascular
• Platelet
• coagulation
• Fibrinolytic
Acquired
• Vascular
• Platelet
• coagulation

57. HEMORRHAGIC DISORDERS
Hemorrhagic syndromes are characterized by a disorder
of one or more factors that participate in hemostasis.
The majority of hemorrhagic syndromes are blood vessel
disorders, platelet number and function disorders, or
coagulation factor disorders:
• vasculopathies
• thrombocytopenias
• thrombocytopathies
• coagulopathies.

58. Vasculopathies
• Vasculopathies may be inherited or acquired. Inherited
forms result from blood vessel structure disorders
(inherited telangiectasia,Rendu-Osler-Weber’s disease)
while acquired disorders can be a consequence of
inflammatory or immune processes that damage blood
vessel walls.
• In clinical practice, acquired disorders are found more
frequently (secondary purpuras, infections,
effects of some drugs, allergic purpura, effect of aspirin,
vitamin C deficiency, etc.).

59. Thrombocytopenias
• Thrombocytopenia, or reduced circulating platelet
count, can be inherited or acquired; the acquired form
being more frequent.
• Thrombocytopenia occurs as a result of:
– decreased platelet formation with normal platelet
survival time (effects of irradiation, drugs, malignant
tissue pressure on bone marrow, leukemias, aplastic
anemias) or
− increased platelet degradation or platelet deposit in
spleen with decreased platelet survival (DIC, effects
of drugs, bacterial or viral infections, inherited idiopathic
thrombocytopenic purpura, chronic leukemias, lupus
erythematosus,Hodgkin’s disease, massive transfusions
and liver cirrhosis).

60. Thrombocytopathies
• Inherited Qualitative Platelet Disorders may be due
to abnormalities of
1. platelet membrane glycoproteins,
- Glanzmann Thrombastenia, abnormal GPIIb/IIIa
– Bernard-Soulier Syndrome, abnormal GPIb, GPIX and
GPV
– platelet-type of vWD, abnormal GPIb
2. platelet granules,
• These may occur due to absence of granules in
platelets, storage pool disorder (characterized by
disturbed platelet aggregation to collagen, adrenaline
and thrombin), or disturbed release (absence of T A2).

61. 3. platelet coagulant activity, or
4. signal transduction and secretion.
• defects in arachidonic acid metabolism,
• cyclooxigenase deficiency, platelets unable to produce
thromboxane; endothelium may not produce
prostacyclin,
• thromboxane synthesis deficiency, and
• defects in platelet secretion and the second wave of
platelet aggregation, found in response to epinephrine or
ATP.

62. Coagulopathies

63. ACQUIRED BLOOD CLOTTING
DISORDERS
They occur in:
– vitamin K deficiency,
– liver diseases,
– liver transplantation,
– disseminated intravascular coagulation,
– renal diseases,
– primary pathological fibrinolysis
– during the course of anticoagulant therapy.

64. • The extent and severity of periodontal disease
determines the necessity for a surgical or nonsurgical
treatment approach in its management.
• The nature and severity of an acquired bleeding
disorder, and the degree of invasive dental
procedures, determines the need to modify the treatment
to be provided.
• Various Illnesses, along with pharmacotherapy,may
contribute to the tendency for excessive bleeding.

65. Pre-operative management of patients starts with a medical
history focusing on the previous bleeding history of the
patient and medical conditions associated with bleeding.
Presence of following illness may need a modification in
treatment protocol to minimize the risk of intra-operative
and postoperative bleeding.
• Chronic renal failure
• Lack of vitamin K
• Liver failure
• Aspirin
• Antiplatelet medication
• Anticoagulant therpay

66. Intra-operative measures include a number of systemic and local
measures administered prior to, or during, the procedure to prevent
unlikely bleeding diathesis.
Surgeries • Platelet count should be assessed
• Iv infusion 1 hr before
• Level should be 50% higher in plasma for
Missing factors Regional anesthesia
Scaling and root
planing • Antifibrinolytic mouthwash (Lee , Boyle)
LA • regional anesthesia should be avoided
• Conservative design
Flap • Mandibular molar
Prevention of • Curettage of extraction socket
infection • Granulation tissue

67. Hemostatic agent Other means Hard tissue
• Absorbable • Sponge • Bone burnishing
gelatin • Surgical splint • Bone wax
• Absorbable • Electrocautery
collagen • Laser
• Microfibrillar • Moistened or
collagen hemostatic
• Oxidised soaked gauze
cellulose
• Thrombin
• Tranexamic acid
• Fibrin glue
• PRP

68. General recommendations is crucial for preventing
bleeding, postoperatively.
Prohibition of Liquid , high Antifibrinolytic
Rinsing protein diet mouthwash
Pain
Antibiotics
medication

69. References :-
• Textbook of Medical Physiology ,10th edition,Hall &
Guyton
• Essentials of hematology , Shirish M Kawthalkar
• Periodontal Medicine, Rose
• Bleeding disorders and periodontology, Philip
Vassilopoulos & Kent Palcanis , Periodontology
2000, Vol. 44, 2007, 211–223.
• Coagulation Pathway and Physiology, Jerry B. Lefkowitz
• Hemostasis And Hemorrhagic Disorders, R. Baklaja, M.
C. Pešic´, J. Czarnecki
• Platelet function analysis,Paul Harisson, Blood Reviews
(2005) 19, 111–123

70. Thank You