Introduction to bleeding disorders. Flashcards Preview

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Flashcards in Introduction to bleeding disorders. Deck (39):
1

In haemostatic balance what 2 factors are balance

bleeding (anti-coagulant)
clotting (procoagulant)

2

what is the first step which results in the activation of a haemostatic plug forming

disruption to the BV wall

3

what molecule do platelets adhere to

vWF

4

what molecule does vWF attach to

collagen

5

what molecule does thrombin activate

fibrin

6

where does thromboxane synthesis take place

inside the platelet

7

what is the purpose of thromboxane

contacts blood vessels and activates platelets.

8

2 important receptors found on the plasma membrane of a platelet.

IIaIIIA- receptor for fibrinogen= platelet aggregation.
IBIX- receptor for vWF=platelet adhesion

9

aspirin inhibits cycloxygenase, what is the function of cycloxygenase

produce thromboxane.

10

what molecule does clopidogrel inhibit

ADP

11

what happens in the extrinsic pathway.

1. Tissue factor expressed on injurged cells= damage BV
2. Activates VII-VIIa, this activates X- Xa, this activated prothrombin to thrombin which converts fibrinogen to fibrin.

12

what happens in the intrinsic pathway

1. XIIa-XIIa, which converts XI-XIa, which converts IX-IXa.
2. activates X- Xa, this activated prothrombin to thrombin which converts fibrinogen to fibrin.

13

what are the procoagulant molecules.

platelets
clotting factors

14

what are the anticoagulant molecules

Protein C
Protein S- co factor protein C.
Anti-thrombin III
Fibrinolytic system- breaks down the clot when it is no longer needed.

15

what is the fibrinolytic pathway

Tissue plasminogen factor (TPA) breakdown plasminogen to plasmin.
Plasmin then converts fibrin into a fibrin degradation product.
This happens on the surface of a clot.
TPA use for clot busting in acute MI.

16

What are the different types of bleeding disorders

congenital
acquired
platelet
vessel wall
coagulation defect

17

What drug can cause abnormal platelet function (Blood thinner)

aspirin

18

what condition is caused by abnormal interaction between the vessel wall and platelets

von willibrand factor.

19

what are the major difference between platelet and coagulation defects

platelet defects- affect skin and mucosal membranes and form petichae and bruising on skin
coagulation defects- affect spreading haematoma and haemoarthrosis, affect retroperrtioneal bleeding which is often recurrent and prolonged.

20

do petichae blache when pressure is applied

no.

21

Von Willebrand disease is caused by a deficiency in which molecule

platelets

22

what type of genetic disorder is von willebrand factor

autosomal dominant.

23

what factor is reduced in von willebrand disease

factor 8 (FVIII)

24

which blood group has lower levels of von willebrand factor

blood group O

25

what are common consequences of von willebrand disease

• Mucocutaneous bleeding including menorrhagia
• Postoperative and post partum bleeding

26

are there different types of von willebrand factor, in terms of disease.

yes there are mild and more severe forms.

27

what is the treatment that is provided for von willebrand factor disease

Antifibrinolytics: tranexamic acid (important in mouth bleeds)
DDAVP- releases VWF from stores in endothelial cells.
factor concentrates of VWF
vaccination against hepatitis
COCP (combined oral contraceptive pill) for menorrhagia

28

haemophilllia a is a deficnecy in which factor

factor VII

29

haemophillia b is a deficnency in whihc factor

factor IX.

30

what type of genetic inherited disorder are the haemophillias

x-linked.

31

what is the function of the drug DDAVP

release vWF form endothelial cells.

32

are there degrees of severity in haemophilia

yes
normal, mild, moderate and severe.

33

what are the different types of bleeds occur in haemophilia

spontaneous/post traumatic
joint bleeding- haemarthorosis.
muscle- haemorrhage
soft tissue- mouth bleed and intracranial bleed.
life threatening bleed in the airways.

34

what is acute and chronic haemophilic arthropathy- which is a complication of haemophilia

swollen bone deformity
muscle wasting

35

treatment for haemophilia

Replacement of missing clotting protein
DDAVP
factor concentrates
antifibrinolytic agents
vaccine for hep A and hep B

36

complications of treatment from haemophilia treatment

Infections- Hep A,B,C,G, HIV, paravirus, vCJD.

Inhibitor development (more common in haemophilia A)- patients become resistant to replacement therapy.

37

How is haemophilia managed

Haemophilia Centres and Comprehensive care Centres.
Multidisciplinary Approach
Home treatment
Patient Education and Social Support
Physiotherapy
Orthopaedic Advice & Treatment
Treatment & Diagnosis of Liver Disease
Specialised Management for HIV Positive Patients
Genetic Counselling & Parental Diagnosis

38

appropriate investigations if you suspect a bleeding disorder.

Full blood count and blood film
Coagulation screen
Mixing studies if abnormal results
Refer to a haematologist if history suspicious
Von Willebrand profile
platelet function tests

39

what conditions does the bleeding /normal coagulation screen show.

 Thrombocytopenia
 Disorder of platelet function
 vWD
 Factor XIII deficiency
 Mild coagulation factor deficiency
 Vascular disorder
 Disorder of fibrinolysis: rare