Anticoags Flashcards
(123 cards)
1
Q
coag factors are ___
A
enzymes
2
Q
each step of the cascade amplifies the ___
A
initial signal
3
Q
coag factors are made in the ___
A
liver
4
Q
“Final pathway” results in:
A
conversion of prothrombin (II) to thrombin
which catalyzes the conversion of fibrinogen to fibrin
5
Q
fibrin activates the ____
A
fibrinolytic system (plasmin, tissue plasminogen activator (tPA))
6
Q
Homeostasis of the cascade is maintained by balance of
A
procoagulants (coag factors) endogenous anticoagulants (proteins C & S, antithrombin III)
7
Q
proteins C and S are important for ___
A
warfarin dosing
8
Q
antithrombin III is important for ___
A
heparin dosing
9
Q
purpose of fibrinolytic system
A
degrades fibrin
10
Q
fibrinolytic system results in:
A
fibrin split products (FSP) AKA fibrin degredation products (FDPs) Fibrin dimers (d-dimers)
11
Q
increased fibrin degradation product or d dimer levels suggest presence of ___
A
thrombi
12
Q
consequence of inappropriate thrombosis:
A
venous thrombi
arterial thrombi
13
Q
venous thrombi:
A
DVT
Red thrombus AKA venous stasis thrombi
VTE (venous thromboembolism)
14
Q
arterial thrombi are __ driven
A
platelet driven
15
Q
complication of venous thrombi
A
pulmonary embolism
16
Q
arterial thrombi
A
white thrombus
17
Q
complication of arterial thrombi
A
strokes, myocardial infarction
18
Q
thrombosis risk factors
A
surgery cancer immobility varicose veins pregnancy
19
Q
potential complication of anticoagulant agents
A
BLEEDING
20
Q
complications of anticoagulation agents are NOT an ___. it is an extension of their ___
A
allergy; MOA
21
Q
heparin binds to ___
A
antithrombin III
22
Q
heparin binding requires specific _____
A
pentasaccharide sequence
23
Q
Heparin’s limitations
A
heparin activates platelets directly
Heparin can dinduce immune response in the form of HIT/HITTs
Heparin exhibits nonlinear dose response
Heparin increases affinity of thrombin for fibrin
24
Q
unfractionated heparin is a :
A
heterogenous mix of sulfated glycosaminoglycans
25
only ___ of UFH molecules have the pentasaccharide
~1/3
26
UFH antithrombin complex is approx ______ x > anticoagulant than antithrombin alone
100-1000x
27
UFH is only effective on ____ fibrin
soluble (non clot-bound fibrin)
28
UFH prevents the ____ of the thrombus
growth/propagation
29
UFH allows the patient's fibrinolytic system to ___
degrade the clot
30
UFH is measured by the ______
activated partial thromboplastin time aPTT)
31
DVT prophylaxis -- subQ heparin
UFH
| 5,000 units SubQ q12h or q8h
32
Risk of HIT is that of ___ UFH
IV (increased risk)
33
Advantages of UFH
```
immediate anticoag
measured by aptt
effects reversed by protamine
prevents propagation of a clot
may be given subQ for prophylaxis
usually done by Pharmacy Dosing Service
```
34
disadvantages of UFH
```
non-linear kinetics
frequent lab tests required
increased risk of bleeding
potential for life-threatening immune-mediated thrombocytopenia "HIT)
minimal effect on interior of the clot
```
35
___ is used to reverse UFH heparins
protamine sulfate
36
MOA of protamine sulfate
combines with strongly acidic heparin
37
2 types of HIT
```
HIT 1 (non-immune) 10%
HIT II (immune) VERY BAD <3% of patients
```
38
HIT I is transient due to ___
clumping of platelets (actually an artifact)
39
HIT-I happens ___
immediately
40
HIT II is seen after ___ of heparin
5-10 days
41
in HIT II, platelet count falls by ____ from baseline
>50%
42
HIT II is immune mediated by ____
anti-platelet factor 4
| test for PF4
43
LMWH have a more favorable ___
benefit/risk ration
44
LMWH have predictable ____
dose response ratio
45
LMWH ahs ___ dosing
weight base
46
LMWH has less risk fo ___
HIT (if started initially)
47
LMWH (fractionated) has ___ administration
subQ
48
Available LMWH agent
enoxaprin (lovenox)
49
indications for LMWH
ACS treatment
DVT
PE
VTE prophylaxis in high risk populations
50
Dose of lovenox for acute DVT w/ or w/o PE (inpatient)
1mg/kg/dose (roundedO subQ q12h
OR
1.5mg/kg (rounded) subQ once daily
51
lovenox dose for acute DVT w/ or w/o PE (outpatient)
1mg/kg/dose (rounded) subQ q12h
52
vitamin k antagonists inhibit ___
post-translational carboxylation of coag factors II (prothrombin), VII, IX, X
53
vitamin K antagonists inhibit two vitamin k sensitive ___
synthetic enzymes
54
warfarin is reversed with ____
pharmacological doses of vitamin K (phytonadione; mephyton)
55
doses of vitamin K to reverse warfarin
2.5-10mg PO (5mg tablet)
| 1-10 mg IVPB (rare risk of anaphylaxis w/ rapid infusion)
56
vitamin K antagonists are often started with heparin for
Afib, DVT, PE
57
D/C IV heparin when ____
warfarin is therapeutic
58
warfarin takes ____ for full anticoagulation
5-7 days
59
when using warfarin, measure effects wiht ___ and ___
prothrombin time (PT) and international normalized ratio (INR)
60
Therapeutic INR ranges for Afib, DVT< PE
2-3
61
therapeutic INR ranges for mechanical heart values (NOT porcine)
2.5-3.5
62
each dose of warfarin takes ____ to take effect
~48h
63
complication of starting 10mg warfarin daily
possibility of warfarin induced skin necrosis
64
INR 3-5, no sig bleeding
lower or hold next dose
| resume when INR nears 2-3
65
INR 5-9; no sig bleeding
omit next 1-2 doses. Monitor INR, resume when INR nears 2-3
66
INR >9; no sig bleeding
hold warfarin.
give vit k 5-10 mg PO
Monitor INR next 2-3 days, give addl vit k if needed
67
any increased INR; serious bleeding
hold warfarin
give vit k 10 mg via SLOW IVPB AND FFB
may repeat vit K IV q12h
68
any increased INR; life threatening bleeding
hold warfarin.
| give PT complex & vit K 10mg IVPB (slow); repeat if necessary
69
drugs that inhibit CYP2C9 increase ___ an d___
INR and risk of bleeding
70
drugs that inhibit CYP2C9:
bactrim
| flagyl
71
drugs that INDUCE CYP2C9 decrease ___ and INCREASE ___
INR and the increase the risk of thrombosis
72
drugs that induce CYP2C9
contraceptives
73
sources of high dietary folate
beef, pork liver
green teas
leafy green vegetables
spinich
74
___ is in prefilled syringes
Fondaparinux (Arixtra)
75
Anti-Factor Xa inhibitors is a ___
synthetic pentasaccharide
76
Anti Factor Xa inhibitors are mainly ___ eliminated
renally
77
Anti factor Xa inhibitors are contraindicated in ___
CrCl <30
78
unlabeled use of anti factor Xa inhibitors:
DVT px in patients w/ h/o HIT
79
oral direct Xa inhibitor
xarelto (rivaroxaban) Bayer
80
oral direct xa inhibitor w/ no lab monitoring
xarelto
81
recent reversal agent of xarelto
aadexant alfa
82
MC adverse affect of xarelto
bleeding
| >5%
83
bivalent direct thrombin inhibitors
lepirudin
bivalrudin
desirudin
84
univalent DTIs
argatroban
| dabigatran
85
DTIs may be used in pts w/ ____
h/o HIT II
86
used to treat HIT
argatroban
87
argatroban is given ___ and monitored w/ ___
IV; monitored w/ PTT
88
Argatroban is NOT ___
really eliminated. (used inpatients w/ HIT and poor renal function)
89
AZ withdrew application of Ximelagatran in ____
2006
90
Dabigatran requires no ____
lab testing
91
new reversal agent for dabigatran was released in ___
2015
92
dabigatran (pradaxa) reversal agent
idarucizumab (prdxbind)
93
idarucizumab is humanized ___
monoclonal antibody
94
MOA of Idarucizumab
binds to pradaxa
95
dosage of praxbind
two consecutive 2.5 g doses given IV
96
cost of PRaxbind
3,500$
97
decoy protein
factor Xa
98
Andexanet alfa corrects
```
apixaban
rivaroxaban
edoxaban
enoxaprin
fondaparinux
```
99
anti platelet drugs
glyprotein IIB/IIIa inhibitors
ADP receptor antagonists
others
100
eptifibatide is administered __
IV
101
purpose of eptifibatide
ACS
| PCI and/or stent
102
abciximab (RepPro)
chimeric monoclonal antibody (human/murine)
103
abciximab has numerous ___
adverse effects
104
___ is rarely used
abciximab
105
___ has a black box warning
ticlopidine
106
ticlopidine is reserved for patients:
intolerant to aspirin
| those who failed aspirin therapy
107
clopidogrel is a prodrug converted to ___
unidentified active metabolite
108
clopidogrel ultimately prevents ___
platelet aggregation
109
clopidogrel drug interactions:
decreased activity w/ PPIs via CYP2C19 inhibition
| increased his of restenosis while on PPIs
110
prasugrel is more effective w/ ___
clopidogrel or ticlopidine
111
prasugrel has less inhibition by ___
PPIs
112
platelet antagonists:
aspirin
113
aspirin inhibits platelet aggregation by ___
acetylation of ADP receptor
114
(aspirin) acetylation of ADP receptor lasts ___
life of the platelet
115
benefits of aspirin are waited against adverse effects:
```
GI bleed (minimal at low doses)
Tinitis (minimal at low doses)
```
116
don't chew ___ aspirin
baby
117
mechanisms of dipyridamole
platelet aggregation inhibitor
| vasodilator
118
dipyridamole is used w/ ___ in patients w/ ___
warfarin; mechanical heart valves (rarely)
119
dipyridamole is used as a ___ in CAD
diagnostic agent (persantine stress test) frequently
120
Available tissue plasminogen activators
alteplase (activase, cathflo)
121
tPA (alteplase) is used for
lysis of coronary artery thrombi in AMI
management of ischemic stroke (more common0
lysis of occluded ports of catheters
122
stroke dose of tPA (alteplase)
0.9mg/kg
| load 0.09 mg/kg (10% of total dose) over one min; followed by 0.81 mg/kg (90% of dose) CIV over 1 hr
123
max dose of tPA
90mg
