2. INTRODUCTION
● It is caused by the abnormalities of hemostasis, coagulation, characterized by
local or extensive skin .
● Steps of hemostasis :-
- Vasoconstriction
- Formation of platelet plug
- Blood clotting or coagulation
3. VASOCONSTRICTION
● Vasoconstriction is produced by vascular smooth muscle cells.
● The smooth muscle cells are controlled by vascular endothelium, which
releases intravascular signals to control the contracting properties.
● When a blood vessel is damaged, there is an immediate reflex, initiated by
local sympathetic pain receptors, which helps promote vasoconstriction.
● The damaged vessels will constrict (vasoconstrict) which reduces the amount
of blood flow through the area and limits the amount of blood loss.
4. ● Collagen is exposed at the site of injury, the collagen promotes platelets to
adhere to the injury site.
● Platelets release cytoplasmic granules which contain serotonin, ADP and
thromboxane A2, all of which increase the effect of vasoconstriction.
● The spasm response becomes more effective as the amount of damage is
increased.
● Vascular spasm is much more effective in
smaller blood vessels.
5. FORMATION OF PLATELET PLUG
● Platelets adhere to damaged endothelium to form a platelet plug and then
degranulate.
● This process is regulated through thromboregulation.
● Plug formation is activated by a glycoprotein called Von Willebrand factor
(vWF), which is found in plasma.
● When platelets come across the injured endothelium cells, they change shape,
release granules and ultimately become ‘sticky’.
● Platelets express certain receptors, some of which are used for the adhesion
of platelets to collagen.
6. ● When platelets are activated, they express glycoprotein receptors that interact
with other platelets, producing aggregation and adhesion.
● Platelets release cytoplasmic granules such as adenosine diphosphate (ADP),
serotonin and thromboxane A2.
● Adenosine diphosphate (ADP) attracts more platelets to the affected area,
serotonin is a vasoconstrictor and thromboxane A2 assists in platelet
aggregation, vasoconstriction and degranulation.
● Platelets alone are responsible for stopping
the bleeding of unnoticed wear and tear
of our skin on a daily basis.
7. CLOT FORMATION
● Once the platelet plug has been formed by the platelets, the clotting factors
are activated in a sequence of events known as 'coagulation cascade' which
leads to the formation of Fibrin from inactive fibrinogen plasma protein.
● Thus, a Fibrin mesh is produced all around the platelet plug to hold it in place;
this step is called "Secondary Hemostasis".
● During this process some red and white blood cells are trapped in the mesh
which causes the primary hemostasis plug to become harder: the resultant
plug is called as 'thrombus' or 'Clot'.
8. ● Therefore 'blood clot' contains secondary hemostasis plug with blood cells
trapped in it.
● Though this is often a good step for wound healing, it has the ability to cause
severe health problems if the thrombus becomes detached from the vessel
wall and travels through the circulatory system.
● If it reaches the brain, heart or lungs it could lead to stroke, heart attack, or
pulmonary embolism respectively.
9.
10.
11. EXTRINSIC PATHWAY
● The extrinsic pathway is activated by external trauma that causes blood to
escape from the vascular system.
● This pathway is quicker than the intrinsic pathway.
● It involves factor VII.
12.
13. INTRINSIC PATHWAY
● The intrinsic pathway is activated by trauma inside the vascular system, and is
activated by platelets, exposed endothelium, chemicals, or collagen.
● This pathway is slower than the extrinsic pathway, but more important.
● It involves factors XII, XI, IX, VIII.
14. COMMON PATHWAY
● Both pathways meet and finish the pathway of clot production in what is known
as the common pathway.
● The common pathway involves
factors I, II, V, and X.
16. PLATELETS
● Thrombocytopenia- it is when u have a low number of platelets.
- This can put you at risk for mild to serious bleeding.
- The bleeding could be external or internal. There can be various causes.
- If the problem is mild, you may not need treatment.
- For more serious cases, you may need medicines or blood or platelet
transfusions.
17. ● Signs and symptoms :- bleeding gums
- Nosebleeds
- Purpura in forearms
- Petechiae in feet
● Causes :- inherent or acquired
- Dehydration
- Vitamin B12
- Leukemia
- Folic acid deficiency
19. ● Thrombocytosis - If your blood has too many platelets, you may have a
higher risk of blood clots.
- When the cause is not known, this is called thrombocythemia.
- It is rare. You may not need treatment if there are no signs or symptoms.
- In other cases, people who have it may need treatment with medicines or
procedures.
21. ● Von Willebrand Disease - in this platelets do not work as they should.
- VWF binds factor VIII, a key clotting protein, and platelets in blood vessel walls,
which help form a platelet plug during the clotting process.
- For example, in your platelets cannot stick together or cannot attach to blood
vessel walls.
- This can cause excessive
bleeding.
- There are different types of in
von Willebrand Disease;
treatment depends on which
type you have.
22. ● Type 1. In this most common form of von Willebrand disease, levels of
von Willebrand factor are low. In some people, levels of factor VIII also are
low. Signs and symptoms are usually mild.
● Type 2. In this type, which has several subtypes, the von Willebrand factor
you do have doesn't function properly. Signs and symptoms tend to be
more significant.
● Type 3. In this rare type, von Willebrand factor is absent and levels of
factor VIII are low. Signs and symptoms may be severe, such as bleeding
into the joints and muscles.
● Acquired von Willebrand disease. This type isn't inherited from your
parents. It develops later in life
23. ● Signs and symptoms :- bruising
- Nosebleeds
- Bleeding gums
- Heavy menstrual periods
- Internal bleeding
● Complications:- Anemia
- Swelling and pain
- Death from bleeding
24. ● Diagnosis :- Von Willebrand factor antigen- This test determines the level of
von Willebrand factor in your blood by measuring a particular protein.
- Ristocetin cofactor activity- This test measures how well the von Willebrand
factor works in your clotting process. Ristocetin, which is an antibiotic, is used
in this laboratory testing.
- Factor VIII clotting activity- This test shows whether you have abnormally low
levels and activity of factor VIII.
- Von Willebrand factor multimers- This test evaluates the specific structure of
von Willebrand factor in your blood, its protein complexes (multimers) and
how its molecules break down. This information helps identify the type of von
Willebrand disease you have.
26. Petechiae
● a small red or purple spot on the body caused by minor haemorrhage, < 2mm
in diameter.
● Symptoms:-hematoma
- bleeding or bruising easily
- bleeding gums
- hemarthrosis
- unusually heavy menstrual periods
- nosebleeds
27. ● Causes :-local injury or trauma causing damage to the skin
- Sunburn
- allergic reactions to insect bites
- various autoimmune diseases
- viral and bacterial infections
- a lower than normal blood platelet level
- medical treatments for cancer
- leukemia
- after violent vomiting or coughing
- strenuous activity
- Sepsis
- scurvy
28. ● Treatment :-antibiotics
- corticosteroids
- azathioprine (Azasan, Imuran), methotrexate (Trexall, Rheumatrex), or
cyclophosphamide.
- cancer treatments
● Complication :-damage to the kidneys, liver, spleen, heart, lungs, or other
organs
- various heart problem
- infections that can occur in other parts of the body
29. PURPURA
● The appearance of red or purple discoloration on the skin that do not blanch
on applying pressure,it measure 0.3-1 cm.
● Causes:-disorders that affect blood clotting
- certain congenital disorders such as telangiectasia or Ehlers-Danlos syndrome
- certain medications, including steroids and those that affect platelet function
- weak blood vessels
- inflammation in the blood vessels
- scurvy
30. ● Types :-Thrombocytopenic purpuras - platelet counts are low, suggesting an
underlying clotting disorder.
- Nonthrombocytopenic purpuras - platelet levels are normal, suggesting
another cause.
● Symptoms:-Low platelet count
- bleeding gums or nose
- blood in urine or bowel movements.
- swollen joints, particularly in the ankles and knees.
- Gut problems such as nausea, vomiting, diarrhea, or stomach pain.
- Kidney problems, particularly protein or blood in the urine Excessive
tiredness.
32. ECCHYMOSIS
● An ecchymosis is a subcutaneous spot of bleeding with diameter larger than 1
centimetre .
● It is similar to a hematoma, commonly called a bruise.
● Causes :- anticoagulants, such as aspirin and warfarin
- varicose veins
- Surgery
- platelet abnormalities, such as a low platelet count
- fractures and broken bones
33. - end-stage kidney disease
- hemophilia and other bleeding disorder
- Leukemia
- dengue fever
● Treatment :- anti-inflammatory drugs, such as ibuprofen.
34. HEMARTHROSIS
● Hemarthrosis is a condition that occurs as a result of bleeding into a joint
cavity.
● A bleeding into joint places, mostly seen in haemophilia A or haemophilia B.
● Signs :-warmth in the joint
- swelling in the joint
- tingling in the joint
● Symptoms :- the skin over the joint feels warm
- Swelling
- Stiffness
- Pain
- loss of motion
- discomfort
35. ● Causes :-trauma caused by a sprain or injury
- blood-thinning drugs, known as anticoagulants
- infection in the joint
- some types of arthritis, such as osteoarthritis and hemophilic arthritis
- some types of cancer, commonly leukemia
● Treatment :-
❏ Synovectomy : This procedure involves the removal of the synovium, which is
the lining of a joint.
❏ The synovium helps lubricate the joint and also helps to remove any fluid
and debris from the joint.
❏ Removing this lining stops the bleeding cycles.
❏ There are three types of synovectomy:
36. - Radioactive: A doctor injects a radioactive fluid into the joint.
- Arthroscopic: A surgeon makes small incisions in the joint and removes the
synovium, using a small camera for accuracy.
- Open: Full surgery involves opening the joint completely to remove the
synovium.
● Other types of surgery as treatment for joint pain include:
- Cheilectomy: Removal of small bony growths on the joint.
- Arthrodesis: Fusion of the joint.
- Osteotomy: Removal of a piece of bone in the leg to straighten it and reduce
pain
37. BLEEDING DISORDER CAUSED BY COAGULATION
● Haemohphilia - Hemophilias are common hereditary bleeding disorders
caused by deficiencies of either clotting factor VIII or IX.
- Hemophilia A (factor VIII deficiency), which affects about 80% of patients
with hemophilia, and hemophilia B (factor IX deficiency) have identical
clinical manifestations and screening test abnormalities.
- Both are X-linked genetic disorders.
● Types :- Haemophilia A
- Haemophilia B
- Haemophilia c
38.
39.
40. HAEMOPHILIA A
● Hemophilia A, also called factor VIII (FVIII) deficiency or classic hemophilia, is a
genetic disorder caused by missing or defective factor VIII, a clotting protein.
● Although it is passed down from parents to children, about 1/3 of cases are
caused by a spontaneous mutation, a change in a gene.
● VIII factor is located in X chromosome.
● Signs and symptoms:- hemarthrosis
- Nose bleeds
- Blood in urine
- Easily get bruise
- headache
41. ● Diagnostic tests:- APTT : Prolonged
- PT & BT : normal
- TT & fibrinogen : normal
- PLT count : normal
- F VIII activity : decreased
- DNA analysis : antenatal diagnosis and carrier detection
● Treatment :- F VIII replacement therapy
- DDAVP
- Antifibrinolytic agents
42. HAEMOPHILIA B
● Also known as factor IX deficiency.
● Signs and symptoms:- hemarthrosis
- Nose bleeds
- Blood in urine
- Easily get bruise
- headache
● Diagnostic tests:- APTT : Prolonged
- PT & BT : normal
- TT & fibrinogen : normal
- PLT count : normal
- F IX activity : decreased
- DNA analysis : antenatal diagnosis and carrier detection
43. TEST TO DIAGNOSE BLEEDING DISORDER
● BT
● Platelet count
● Activated partial thromboplastin time (aPTT)
● Prothrombin time (PT)
● Thrombin time (TT)
44. BLEEDING TIME
● A bleeding time test determines how quickly your blood clots to stop bleeding.
● The test involves making small punctures in your skin.
● A healthcare provider performs the test by following these steps:
- They clean the puncture site with an antiseptic to minimize the risk of infection.
- They place a pressure cuff around your upper arm and inflate it.
- Next, they make two small cuts on your lower arm. These will be deep enough
to cause slight bleeding. You might feel a slight scratch when they make the
cuts, but the cuts are very shallow and shouldn’t cause much pain.
- They remove the cuff from your arm.
45. - Using a stopwatch or timer, they blot the cuts with paper every 30 seconds
until the bleeding stops. They record the time it takes for you to stop bleeding
and then bandage the cuts.
- Usually, if the cuts continue to bleed after 20 minutes, the healthcare provider
notes that the bleeding time was over 20 minutes.
46. APTT
● The partial thromboplastin time (PTT) or activated partial thromboplastin time
(aPTT or APTT) is a blood test that characterizes coagulation of the blood.
● A historical name for this measure is the kaolin-cephalin clotting time (KCCT)
reflecting kaolin and cephalin as materials historically used in the test.
● It measures the overall speed at which blood clots by means of two
consecutive series of biochemical reactions known as the intrinsic pathway
and common pathway of coagulation.
● PTT measures the following coagulation factors: I , II , VIII , X , XI, and XII .
47. ● Procedure :-Blood is drawn into a test tube containing oxalate or citrate,
molecules which act as an anticoagulant by binding the calcium in a sample.
- The blood is mixed, then centrifuged to separate blood cells from plasma .
- A sample of the plasma is extracted from the test tube and placed into a
measuring test tube.
- Next, an excess of calcium is mixed into the plasma sample .
- Finally, in order to activate the intrinsic pathway of coagulation, an activator is
added, and the time the sample takes to clot is measured optically. Some
laboratories use a mechanical measurement, which eliminates interferences
from lipemic and icteric samples.
● A typical aPTT value is 30-40 seconds.
● The reference range of PTT is 60-70 seconds.
48. THROMBIN TIME
● Thrombin is an enzyme in blood that acts on the clotting factor fibrinogen to
form fibrin, helping blood to clot.
● The thrombin time (TT) assesses the activity of fibrinogen.
● When an injury occurs and bleeding begins, the body begins to form a clot at
the injury site to help stop the bleeding.
● Small cell fragments called platelets adhere to, aggregate, and are activated at
the injury site.
● At the same time, the coagulation cascade.
● This test is repeated with pooled plasma from normal patients.
49. ● The thrombin time compares the rate of clot formation to that of a sample of
normal pooled plasma.
● Thrombin is added to the samples of plasma.
● If the time it takes for the plasma to clot is prolonged, a quantitative (fibrinogen
deficiency) or qualitative (dysfunctional fibrinogen) defect is present.
● In blood samples containing heparin, a substance derived from snake venom
called batroxobin is used instead of thrombin.
● Batroxobin has a similar action to thrombin but unlike thrombin it is not
inhibited by heparin.
● Normal values for thrombin time are 12 to 14 seconds.
● If batroxobin is used, the time should be between 15 and 20 seconds.
● Thrombin time can be prolonged by heparin, fibrin degradation products, and
fibrinogen deficiency or abnormality.