Hameostasis

Question 1

What is it called when platelets are reduced in number?

Answer 1

Thrombocytopenia

Question 2

List two causes of impaired thrombocyte production.

Answer 2

-Leukemia
-B12 deficiency

Question 3

Give two examples of conditions where you will find accelerated thrombocyte clearance.

Answer 3

-Immune thrombocytopenia purpura (ITP)
-Disseminated intravascular coagulation (DIC)

Question 4

Give a third reason you can find thrombocytopenia

Answer 4

Pooling and destruction in an enlarged spleen

Question 5

Which 3 drugs commonly caused impaired thrombocyte function?

Answer 5

-Aspirin
-NSAIDs
-Clopidogrel

Question 6

What does aspirin do?

Answer 6

Irriversibly blocks COX which leads to decreased production of thromboxane A2.

Question 7

How does clopidogrel work?

Answer 7

Irreversibly blocks the ADP receptor P2Y12 on platelets.

Question 8

What two functions does VWF have in haemostasis?

Answer 8

-Binding to collagen and capturing platelets
-Stabilising factor VIII

Question 9

What is the inheritance pattern in VWF disease?

Answer 9

Is usually hereditary with autosomal inheritance pattern.

Question 10

Which types of VW disease lead to deficiency of VWF?

Answer 10

Type 1 or 3

Question 11

Which types of VWD lead to normal VWF production but with impaired function?

Answer 11

Type 2

Question 12

What is the overall negative effect of a lack of VWF in haemostasis?

Answer 12

Inability to form the platelet plug

Question 13

What are the clinical features pf disorders of primary haemostasis?

Answer 13

Immediate prolonged heavy bleeding.
Easy spontaneous bruising

Question 14

What are petechiae and purpura caused by and which one does not blanch when pressure is applied?

Answer 14

They are caused by bleeding under the skin and purpura do no blanch when pressure is applied.

Question 15

What is a common feature of thrombocytopenia?

Answer 15

Petechiae

Question 16

In severe VWD what can the bleeding pattern resemble?

Answer 16

Haemophilia due to low FVIII

Question 17

What is the bleeding called when the ‘mark’ is greater than 10mm?

Answer 17

Ecchymosis

Question 18

What are the tests for disorders of primary haemostasis?

Answer 18

-Platelet count, platelet morphology
-PFA100
-Assays of VWF
-Clinical observation

Question 19

What treatment can you give in mild VWF disorders?

Answer 19

Desmopressin (DDAVP)

Question 20

What is haemophilia A caused by?

Answer 20

Factor VIII deficiency

Question 21

What is haemophilia B caused by

Answer 21

Factor IX deficiency

Question 22

What are the acquired causes of coagulation factor production deficiencies?

Answer 22

-Liver disease
-Anticoagulant drugs (Warfarin, DOACs)

Question 23

What is haemophilia?

Answer 23

inability to generate fibrin to stabilise the platelet plug

Question 24

What is the hallmark of haemophilia?

Answer 24

Haemarthrosis (spontaneous joint bleeding)

Question 25

What should be avoided in patients with haemophilia?

Answer 25

Intramuscular injections

Question 26

What is a common cause of a coagulation disorder which results in increased consumption and depletion of coagulation factors?

Answer 26

Disseminated intravascular coagulation

Question 27

Explain the differences in the bleeding patterns between Platelet/Vascular defects and coagulation defects

Answer 27

Platelet/Vascular: -superficial bleeding into skin, mucosal membranes. -Bleeding immediate after injury Coagulation: -Bleeding deep into tissues, muscles, joints -Delayed, but severe bleeding after injury

Question 28

What does Prothrombin time measure?

Answer 28

the extrinsic pathway

Question 29

What does the activated partial thromboplastin time measure?

Answer 29

Measures the intrinsic pathway

Question 30

What drug treatment can be used in haemophilia A to mimic factor VIII?

Answer 30

Emicizumab

Question 31

What are the three contributary factors to thrombosis called?

Answer 31

Virchow's triad: -Blood, dominant in venous thrombosis -Vessel wall, dominant in arterial thrombosis -Blood flow, contributes to both arterial and venous thrombosis

Question 32

What term is used to refer to an increased risk of venous thrombosis?

Answer 32

Thrombophilia