Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Haematology > Anticogulant Drugs > Flashcards

Anticogulant Drugs Flashcards

1
Q

What are you targeting in prevention of venous thrombosis?

A

Secondary haemostasis

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

What is a natural inhibitor of fibrin clot formation?

A

Anti thrombin III

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

What does heparin do?

A

Potentiates antithrombin

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

How long does it take for heparin to work?

A

Immediate

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

How do you give heparin?

A

Subcutaneous

Can also be given IV in rare situations

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

Why isn’t unfractionated heparin used anymore?

A

Very narrow theraputic window - LMWH is better

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

How does heparin potentiate antithrombin?

A

Binds to Antithromibin to stabilise the link between it and thrombin or Xa.

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

What test do you use to monitor heparin?

A

APTT if unfractionated

Anti Xa assay for LMWH but not really used in clinical practice

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

What test do you do to monitor warfarin?

A

INR (PT)

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

What other assay is occasionally used in heparin monitoring?

A

Anti Xa

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

Why is APPT used in heparin monitoring?

A

APPT much more sensitive to heparin therapy

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

Why do you monitor FBC in heparin?

A

Risk of Heparin Induced Thrombocytopenia (HITT)

If platelet count drops call haematology

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

Give a long term risk of heparin

A

Osteoporosis

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

What should you do if you get a low platlet count n someone who is on heparin

A
  • Contact haematology
  • Stop heparin
    Start other anticoagulant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What do you do in the case of bleeding in a patient who is on heparin?

A

Stop heparin

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

Does heparin have a short of long half life

A

Short ~ 12 hours

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

What is the antidote to heparin?

A

Protamine sulphate. This reverses antithrombin effect. Only partially effects LMWH as it does not have an effect on Factor Xa

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

Why does protamine sulphate only partially reverse the effect of LMWH?

A

Does not have an effect on Factor Xa

19
Q

Where is Vitamin K absorbed?

A

Upper intestine

20
Q

What dos Vitamin K require for absorption?

A

Bile salts

21
Q

What clotting factors require Vitamin K?

A 
II
VII
IX
X
Protein C 
Protein S
22
Q

What are the first clotting factors to fall when warfarin is started?

A

Protein C and S

23
Q

Why do you need to have 5 days of initial heparin therapy with warfarin?

A

Different half lives of the clotting factors

24
Q

How does vitamin K activate clotting factors?

A

Carboxylation of glutamic acid

25
Q

Where is warfarin metabolised?

A

Liver - Cytochrome p450 pathway

26
Q

What metabolises warfarin?

A

Cytochrome p450

27
Q

How do you start warfarin therapy?

A

Loading high dose with heparin. Monitor closely and then titrate down
If AF and they haven’t had a blood clot then start slowly

28
Q

When should warfarin be taken?

A

At the same time every day

29
Q

What do you use to monitor warfarin therapy?

A

PT (INR)

30
Q

What is the equation for INR?

A

PT is seconds/Mean normal PT is seconds x International Sensitivity Index

31
Q

What is the target INR in patients on warfarin?

A

2 - 3

32
Q

If you have an INR of 5 are you more at risk of bleeding or clotting?

A

Bleeding

33
Q

What are the side effects of warfarin?

A

Skin bruising
Epistaxis
Haematuria

34
Q

What is the risk of an intracerebral haemmorhage in people on warfarin therapy?

A

1/200 per year

35
Q

How do you reverse warfarin therapy?

A
  1. Omit warfarin dose (this will take several days to get INR back into target range)
  2. Oral vitamin K (takes about 6 hours)
36
Q

What do you do if the INR is above 8 or if there is significant bleeding in a patient on warfarin?

A

Give oral vitamin K

37
Q

What do you do if there is severe bleeding in a patient on warfarin?

A
  1. Stop warfarin
  2. Oral Vitamin K
  3. Clotting factor administration
38
Q

How long does it take for oral vitamin K to work?

A

6 hours

39
Q

What do you give to reverse warfarin therapy if you need an immediate reversal?

A

Clotting factors

40
Q

What are the two classes of new anticoagulants?

A

Oral direct thrombin inhibitors (Dabigatran)

Oral Xa inhibitors (Rivaroxaban)

41
Q

Name a factor Xa inhibitor?

A

Rivoroxabam

42
Q

What is the advantage of Xa inhibitors over thrombin inhibitors?

A

Not renally excreted - won’t cause kidney injury

43
Q

What kind of drug is rivoroxabam?

A

Xa inhibitor

Haematology (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions