HEME 2.6 Flashcards

1
Q

Define anticoagulants

A

substances that prevent the synthesis of fibrin network which inhibits coagulation and the formation of thrombi

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

Define thrombolytics/fibrinolytics

A

substances that promote the destruction of already formed blood clots of thrombi by disrupting the FIBRIN MESH

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

define antiplatelets

A

drungs that reduce the adhesion and aggregation of platelets

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

define antifibrinolytics

A

drugs that promote the formation of clots and prevent excess bleeding

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

True or false: anticoagulants can create an immediate defect in clotting mechinism and should be treated with caution

A

TRUE

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

why must anticoagulants be monitored very closely

A

the range between sufficient therapy and hemorrhagic rist is narrow and varies considerably from patient to patient

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

what must be taken into consideration before starting anticoagulants

A

unrelated drugs can effect the dose of the anticoagulant needed
individual treatment and frequent laboratory tests are imparitive

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

what are the Four classes of anticoagulants

A
  • indirect thrombin inhibitors (heparin)
  • Coumarin anticoagulants (Warfarin)
  • Direct thrombin inhibitors
  • Directs factor X inhibitors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the makeup of Heparin

A

A mixture of heparins with a wide range of molecular weights

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

what are the two most common preparation of heparin

A

Unfractionated heparin (UHF – heparin sodium

Low-molecular-weight heparin (LMWH) – Fragmin, innohep, lovenox

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

what is the mechanism Heperin uses to prevent clots

A

Heparin stimulates antithrombin III, which in turn neutralizes the activity of factor X

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

what does neutralizing the activity of Factor X accomplish

A

Prothrombin cannot be converted into Thrombin, which prevents the fibrin formation from fibrinogen

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

what has heparin been “dubbed” as

A

indirect Thrombin Inhibitor

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

besides neutralizing factor X, what else does heparin accomplish

A

stimulates heparin cofactor ll, which inhibits thrombin

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

how is unfractionated heparin (UHF) administered

A

typically by IV (bolus or infusion)

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

what is UFH usually monitored by

A

APTT (activated partial thromboplastin time)

17
Q

how is low molecular weight heparins andministered

A

sub cutaneous on a body weight basis WITHOUT the need for laboratory testing (in hospital or at home)

18
Q

what is the only major coumarin anticoagulant in the USA

A

Warfarin (coumadin)

19
Q

what can warfarin be used as

A

rodent poisons

20
Q

How does Warfarin work

A

interfering with the hepatic synthesis of Vit. K dependent clotting factors (ll, Vll, lX, X)

21
Q

Warfarin is a long term treatment or prophylaxis of

A

venous thrombosis

PE

22
Q

when is warfarin usually administered

A

post MI or Post op

for prevention of systemic thromboembolism in patients with prosthetic hearts valves or atrial fibrilation

23
Q

how is warfarin monitored

A

INR - for most patients is shoud be between 2-3

24
Q

what are four common drugs that inhibit warfarin

A
  • cimetidine (tagamet)
  • acetominophen (tylenol)
  • High dose, acute alcohol
  • many antibiotics
25
what antibiotics inhibit warfarin
azithromyocin (zithromax) - ciprofloxacin - clarithromycin - erythromycin
26
what may potentiate the effects of warfarin
synthetic thyroid hormones by increase catabolism of many clotting factors
27
what may diminish the desired effects of warfarin
- chronic alcohol use - phenytoin - Oral contraceptives (increase the synthesis of clotting factors)
28
what types of food may decrease the effectiveness of warfarin
foods high in Vit. K
29
how are warfarin overdoses typically treated
Vit. K and transfusions
30
what is the most common side effect of warfarin
bleeeding
31
why shouldn't warfarin be taken while pregnant
contraindicated (catagory X) because it can cross the placenta and is teratogenic