Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Haematology > Haemostasis > Flashcards

Haemostasis Flashcards

1
Q

What is haemostasis?

A

Arrest of bleeding and maintenance of vascular patency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the lifespan of platelets?

A

7-10 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When is Von Willebrand Factor released?

A

When there is vessel endothelial damage which exposes collagen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the screening test for primary haemostats?

A

Platelet count

can measure von Willebrand factor if history indicates it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What converts plasminogen to plasmin? When can it be used as a treatment?

A

tissue plasminogen activator (tPA)

To break down clots e.g. acute stroke

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are D-dimers?

A

Cross-linked Fibrin Degradation Products (FDPs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What 2 factors convert prothrombin to thrombin?

A

Factor V and Xa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What factors are affected in prolonged PT?

A

Tissue factor

Factor VIIa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What factors are affected in prolonged APTT?

A

Factor VIII

Factor IXa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What condition can cause isolated prolonged APTT?

A

Haemophilia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is thrombophilia?

A

Deficiency of naturally occurring anticoagulants (may be hereditary). Therefore, increased tendency to develop venous thrombosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What proteins are involved in natural anticoagulation by switching off factor V and VII?

A

Protein S and Protein C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is primary haemostats?

A

Formation of platelet plug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is secondary haemostats?

A

Formation of fibrin clot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the causes pf platelet functional defects?

A

Hereditary (rare)
Acquired:
- drugs (aspirin, NSAIDs etc)
- renal failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where are all the clotting factors produced?

A

Liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the significance of low albumin in the context of abnormal bleeding?

A

Liver produces both albumin and clotting factors, so if there is low albumin due to liver disease, suggests the liver won’t be producing enough clotting factors either.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the multiple clotting factor deficiencies?

A

Liver failure
Vitmain K deficiency/Warfarin therapy
Complex coagulopathy: DIC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the effect of multiple clotting factor deficiencies on PT and APTT?

A

Both prolonged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What causes Haemorrhagic disease of the newborn and how is it prevented?

A

Babies don’t have dietary intake of vitamin K or any gut flora to make vit K so they have clotting deficiency. Newborns get IM vitamin K to prevent this

21
Q

Why do you get end organ failure in DIC

A

Microvascular thrombus formation

22
Q

If both PT and APTT are prolonged, what does this suggest?

A

Multiple clotting factors problem

23
Q

What happens to D-dimer levels in DIC and why?

A

Increase, due to excess fibrinolysis

24
Q

What are the PT and APTT in haemophilia?

A

PT: normal
APTT: very prolonged (because the problem is with Factor VIII or IX)

25
What is the main component of arterial thrombus vs venous thrombus and what are the targeted treatments in each case?
arterial: platelet-rich clot - treat with anti-platelets Venous: fibrin-rich clot - treat with fibrinolytics and drugs that interfere with fibrin clots (heparin, warfarin etc)
26
What are the complications of PE?
``` pulmonary infarction pleuritic chest pain cardiovascular collapse/sudden death hypoxia right heart strain ```
27
What are the risk factors of VTE?
``` age marked obesity pregnancy puerperium oestrogen therapy previous DVT/PE trauma/surgery malignancy paralysis infection thrombophilia ```
28
Which naturally occurring anticoagulant binds to thrombin?
Anti-Thrombin III
29
What is the commonest hereditary thrombophilia?
Factor V Leiden (Impairs protein C/S)
30
When would you consider hereditary thrombophilia screening?
Venous thrombosis
31
How is hereditary thrombophilia managed?
Advice on avoiding risk Short term prophylaxis - to prevent thrombotic events during periods on known risk (e.g. pregnancy) Short term anticoagulation - to treat thrombotic events Long term anticoagulation - if recurrent thrombotic events
32
What is acquired thrombophilia?
Antiphospholipid antibody syndrome
33
What happens to ATPP in Antiphospholipid syndrome?
It is prolonged - paradoxical as you would expect this make pt prone to bleeding but the clotting factors are unaffected and pts are actually prone to thrombosis
34
How is anti-phospholipid syndrome treated and why?
aspirin and warfarin | anti-platelet and anti-coagulant because there is activation of primary and secondary haemostasis
35
What are the immune causes of thrombocytopenia?
ITP Drugs (penicillin, thiazides, oral hypoglycaemics, heparin, blood transfusion) SLE HIV
36
What drugs are used to prevent strokes?
Atherosclerosis - anti-platelets | AF (fibrin-rich clot in LA) - anti-coagulants
37
What do you monitor in patients on Warfarin?
PT (INR)
38
What do you monitor in patients on unfractionated Heparin?
APTT
39
Give an example of a coumarin anticoagulant
Warfarin
40
What is a complication of long term heparin therapy?
Osteoporosis
41
What is the target INR for most patients in warfarin? | What might make you aim for higher?
2 - 3 | Further event despite warfarin treatment - aim for a max of about 3.5 - 4
42
What are the bleeding complications of warfarin therapy?
``` Mild: - skin bruising - epistaxis - haematuria Severe: - GI bleeds - intracranial bleeds (risk is about 1 in 200) - significant drop in Hb ```
43
How long does it take for vitamin K to reverse the effects of warfarin therapy?
6 hours
44
What can you given for immediate reversal of warfarin therapy in a life-threatening situation?
Administer clotting factors (FFP or factor concentrates)
45
What are the 2 groups of new anticoagulants? Give an example of each
Oral direct thrombin inhibitors e.g. Dabigatran | Oral Factor Xa inhibitors e.g. Rivaroxaban, Apixaban
46
What is the risk of giving Dabigabtran to elderly patients?
Dabigatran is renally excreted so patients with renal impairment are at risk of build-up of the drug - risk of bleeding.
47
What do platelets do in arterial thrombosis?
Plaque rupture due to high pressure environment of arteries Platelets adhere to exposed endothelium and there is release of vWF Platelets become activated - release granules that activate coagulation and recruit other platelets to developing platelet plug platelet aggregation via membrane glycoproteins
48
A 21 year old girl has a history of heavy periods and investigations indicate a defect in primary haemostasis. Her blood count is normal. What is the most likely diagnosis?
Von Willebrand's Disease (primary haemostats failure but normal platelet count)
49
What does an isolated prolonged APTT suggest?
Deficiency of factors involved in the ‘intrinsic’ pathway of coagulation (Factor VIII, IX, vWF [as it binds Factor VIII]) or the presence of an anti-phospholipid antibody (lupus anticoagulant) that is not associated with a bleeding phenotype

Haematology (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions