haemostasis - inherited coagluative disorders

Question 1

normal homesostasis steps

Answer 1

1) localised vasoconstriction at site of injury
Happen in parallel:
Primary
2) adhesion of platelets to damaged vessel wall and formation of a platelet aggregate or plug
Secondary
3) activation of coagulation cascade leading to fibrin formation, reinforcing the platelet plug
Then
4) activation of the fibrinolytic system which digests the haemostatic plug, re establishing vascular patency

Question 2

platlets

Answer 2

small non nucleated cells
fragmetns of megakaryocyte cytoplasm
essential for primayr haemostatic plug

Question 3

thrombocytopenia

Answer 3

reduced platlet count

Question 4

thrombocytotsis

Answer 4

increased platlet count

Question 5

coaglulation cascade is initiated by

Answer 5

tissue factor damage

factor 7a

Question 6

once coagulation is initiated what is triggered

Answer 6

• 10 to 10 a
• 9 to 9a, factor 8 co factor to amplify 10 to 10a
• form factor 2a (thrombin)
• this catalyses fibrinogen (soluble) to fibrin(insoluble)

Question 7

types of bleeding

Answer 7

primary haemostasis

secondary haemostasis

Question 8

primary haemostasis

Answer 8

• involves vessel wall, platelets and von Willebrand factor

- present with purpura, bruising, bleeding from cuts, heavy periods and surgical bleeding

Question 9

what does Von willebrand factor do

Answer 9

sticks platelets to vessel wall)

Question 10

secondary haemostasis

Answer 10

• involves coagulation cascade
• presents with joint and muscle haematomas and surgical bleeding
• bruising is not prominent

Question 11

menorrhagia

Answer 11

heavy menstraul periods

Question 12

epistaxis

Answer 12

nosebleed

Question 13

haemoptysis

Answer 13

coughing blood

Question 14

haematemesis

Answer 14

vomiting blood

Question 15

haematuria

Answer 15

blood in urine

Question 16

melaena

Answer 16

black stol due to bleeding from the upper gastrointestinal tract

Question 17

managment of patient with bleeding disorder - history

Answer 17

• easy bruising, spontaneous
• bleeding after cuts/minor injury
• epistaxis (nosebleed)
• menorrhagia (heavy period)
• excessive bleeding after surgery or dental extractions
• family history
• drugs eg aspirin, warfarin, cytotoxins
• alcohol

Question 18

managment of patient with bleeding disorder - examination

Answer 18

• ecchymoses (bruises)
• purpura (pin prick brusining)
• hemarthrosis
• damaged joints
• anaemia (due to bleeding)
• signs of liver disease
• splenomegaly

Question 19

investigations for those with a bleedign disorder

Answer 19

• full blood count (platelet count)
• clotting screen (includes APTT, fibrinogen, prothrombin time PT)
• bleeding time or PFA (automated platelet function analysis)

Question 20

treating hamophilia A

Answer 20

factor 8 concentrate (severe)

• Desmopressin (DDAVP)
• releases factor 8 from endothelium

Question 21

treating haemophilia B

Answer 21

factor 9 concentrate

Question 22

treating thrombocytopenai

Answer 22

platlet transfusion

Question 23

treating wararin overdose

Answer 23

vit K

Question 24

vascular bleeding disorder types and inclusions

Answer 24

1) inherited
- ehlers danlos syndrome (abnormal collagen, skin elasticity)
- hereditary haemorrhagic telangiectasia
2) acquired
- senile purpura
- scurvy
- steroid purpura

Question 25

coagulation factor disorders

Answer 25

haemophilia A/B | von willebrand disease

Question 26

haemophilia B

Answer 26

x linked | factor 9 deficiency

Question 27

haemophilia A

Answer 27

x linked | factor 8 deficiecy

Question 28

von willebrand disease

Answer 28

autosomal dominantn - milder bleeding disorder than haemophilia - clotting factor plus platelet abnormality

Question 29

inheritnce of haemophilia

Answer 29

Man with haemophilia, normal partner - sons will always be unaffected, as they will inherit mothers chromosome, with Y for man which does not affect haemophilia - all daughters will inherit the X, and be carriers for haemophilia (obligate carries) Carrier mother, unaffected male - half will have haemophilia, half daughters will be carriers

Question 30

von willebrand diseas treatment

Answer 30

- DDAVP | - intermediate purity (plasma derived) Factor 8

Question 31

thrombosis

Answer 31

blood coagulation inside a blood vessel

Question 32

arterial thrombosis

Answer 32

- high pressure - platelet rich - examples include myocardial infarction (MI), stroke - treat with antiplatelet drugs

Question 33

venous thrombosis

Answer 33

- low pressure - fibrin rich - examples: deep vein thrombosis (DVT), pulmonary embolism (PE) - treat with anticoagulants

Question 34

risk factors for venous thrombosis

Answer 34

- age, previous VTE - surgery/trauma, immobility, obesity - cancer, serious illness - pregnancy, contraceptive pill, HRT