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Flashcards in HEME 2.6 Deck (31)
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1
Q

Define anticoagulants

A

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

2
Q

Define thrombolytics/fibrinolytics

A

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

3
Q

define antiplatelets

A

drungs that reduce the adhesion and aggregation of platelets

4
Q

define antifibrinolytics

A

drugs that promote the formation of clots and prevent excess bleeding

5
Q

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

A

TRUE

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

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

8
Q

what are the Four classes of anticoagulants

A
  • indirect thrombin inhibitors (heparin)
  • Coumarin anticoagulants (Warfarin)
  • Direct thrombin inhibitors
  • Directs factor X inhibitors
9
Q

what is the makeup of Heparin

A

A mixture of heparins with a wide range of molecular weights

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

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

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

13
Q

what has heparin been “dubbed” as

A

indirect Thrombin Inhibitor

14
Q

besides neutralizing factor X, what else does heparin accomplish

A

stimulates heparin cofactor ll, which inhibits thrombin

15
Q

how is unfractionated heparin (UHF) administered

A

typically by IV (bolus or infusion)

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
Q

what antibiotics inhibit warfarin

A

azithromyocin (zithromax)

  • ciprofloxacin
  • clarithromycin
  • erythromycin
26
Q

what may potentiate the effects of warfarin

A

synthetic thyroid hormones by increase catabolism of many clotting factors

27
Q

what may diminish the desired effects of warfarin

A
  • chronic alcohol use
  • phenytoin
  • Oral contraceptives (increase the synthesis of clotting factors)
28
Q

what types of food may decrease the effectiveness of warfarin

A

foods high in Vit. K

29
Q

how are warfarin overdoses typically treated

A

Vit. K and transfusions

30
Q

what is the most common side effect of warfarin

A

bleeeding

31
Q

why shouldn’t warfarin be taken while pregnant

A

contraindicated (catagory X) because it can cross the placenta and is teratogenic