Brainscape's Knowledge GenomeTM

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


See full index

PHRM 844 Module #2 > VTE Introduction > Flashcards

VTE Introduction Flashcards

1
Q

Pathophysiology

A

venous thrombi are formed in areas of slow/disturbed flow; stasis blood promotes thrombus –> decreased clotting factor clearance
venous thrombi composed of RBCs, fibrin, and few platelets

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

Symptoms result when

A

flow is obstructed
vascular tissue wall becomes inflamed (i.e. surgical procedure/traumatic injury)
thrombus occurs and affects venous blood flow
emboli occur and enter pulmonary circulation
not all DVTs lead to PEs but all PEs come from DVTs

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

3 main things contributing to a blood clot in our pts (virchow’s triad)

A

hypercoagulable state - abnormalities of clotting components (i.e. pregnancy or cancer)
circulatory stasis - abnormalities in blood flow, occurs during long periods of immobility
endothelial injury - abnormality of surfaces in contact with blood flow (i.e. injury of blood vessel)

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

Postthrombotic syndrome

A

long-term complications of DVT caused by damage to venous valves - chronic venous obstruction, caused by venous hypertension, chronic pain and swelling, stasis ulcers, development of infection

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

DVT risk factors

A

age > 40 yrs
family history of DVT
heart failure
immobilization > 10 days
malignancy
myocardial infarction
obesity
othopedic injury
oral contraceptive/estrogen
paralysis
postoperative state
pregnany
prior DVT
varicose veins

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

Nonpharmacologic treatment

A

baseline monitoring
DVT: bed rest (w/ appropriate anticoagulation), elevation of feet, pain management, compression stockings
PE: oxygen, mechanical ventilation, compression stockings

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

Unfractionated heparin

A

rapid, parenteral antigoagulant (most often given as continuous infusion)
variable dose response –> need for aPTT monitoring (time that represents how long it takes the bood to form a clot) - goal 1.5-2.5 time control
AEs: bleeding, thrombocytopenia

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

Weight based dosing for unfractionated heparin

A

monitor aPTT at baseline 6 hours after dose or with each dosage change (for 1st 24hrs); check daily after first day
lower the aPTT is, necessitates an increase in the dose
more elevated aPTT, need to decrease rate or hold infusion for short period of time

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

Heparin associated thrombocytopenia (HAT)

A

non-immune mediated
mild decrease in platelets
occurs around 48-72 hours after administration of heparin
transient, do not need to stop heparin

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

Heparin induced thrombocytopenia (HIT)

A

immune mediated
thrombotic complications
occurs between 7-14 days
one of 2 things to recognize HIT: platelets drop >50% from baseline OR <100,000/mm3

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

HIT management

A

STOP all heparin products
give alternate anticoagulant
do NOT give platelet infusions
do NOT give warfarin until platelet count > 150,000
evaluate for thrombosis

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

Low molecular weight heparin

A

advantages over UFH:
reduced protein binding - good bioavailability, predictable dose response (don’t need to monitor aTTPs)
longer plasma half-life - once or twice daily dosing
smaller molecule - improved SQ absorption
less effect of platelets and endothelium - reduced incidence of HIT and possibly bleeding

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

Monitoring Anti Xa levels

A

measures plasma heparin; consider for children, severe kidney failure, obesity, long courses, pregnancy

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

Fondaparinux

A

use: prophylaxis following THA, TKA, hip replacement, or abdominal surgery; treatment of DVT or PE (1st med used)

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

Fondaparinux considerations

A

do not use if have renal function (CrCl < 30 mL/min)
do not use for prophylaxis with low body weight (<50 kg)
can be used in HIT
no routine monitoring for therapeutic efficacy; can monitor anti-Xa levels
pregnancy category B (safe to use)

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

IV direct thrombin inhibitors

A

all three are reserved for pts diagnosed with HIT
lepirudin
bivalirudin
argatroban (adjust dose based on hepatic impairment; elevated INR, overlap with warfarin until INR >/= 4)

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

NOACs/DOACs

A

direct thrombin inhibitor: dabigatran etexilate
factor Xa inhibitors: rivaroxaban, apixaban, edoxaban, betrixaban

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

Labeled use - postoperative prophylaxis

A

knee or hip replacment surgery

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

Labeled use - non-valvular atrial fibrillation

A

prevention of stroke and systemic embolism in pts with non-valvular atrial fibrillation

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

Labeled use - DVT treatment

A

treatment of a DVT
need to put on an anticoagulant very quickly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Labeled use - PE treatment

A

treatment of pulmonary embolism
need to put on an anticoagulant very quickly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Labeled use - Indefinite anticoagulation (secondary prevention of recurrent DVT and/or PE)

A

reduction in risk of recurrence of DVT and PE following initial 6 months of treatment for them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Labeled use - VTE prophylaxis

A

prophylaxis of VTE in adults hospitalized for an acute medical illness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

NOAC approved indications - postoperative prophylaxis

A

dabigatran, rivaroxaban, apixaban

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

NOAC approved indications - non-valvular atrial fibrillation

A

dabigatran, rivaroxaban, apixaban, edoxaban

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

NOAC approved indications - DVT/PE treatment

A

dabigatran, rivaroxaban, apixaban, edoxaban

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

NOAC approved indications - secondary prevention of recurrent DVT/PE

A

rivaroxaban, apixaban

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

NOAC approved indications - VTE prophylaxis

A

rivaroxaban, betrixaban

29
Q

Warfarin available doses

A

1, 2, 2.5, 3, 4, 5, 6, 7.5, 10
all tabs scored, meant to split in half as needed

30
Q

Challenges of warfarin

A

narrow therapeutic window (range considered to be safe is very close to the range considered to be unsafe)
considerable inter-subject variability (have to individualize warfarin dosing)
drug and diet interactions
labs difficult to standardize (INR monitoring is standardized)
good PK/PD understanding by both patient/provider

31
Q

Warfarin MOA

A

does not effect circulating factors or previously formed thrombi (stops body from making new ones)
inhibits enzymes responsible for cyclic conversion of vit K
inhibit synthesis of vit K dependent clotting factors - factors II, VII, IX, X, protein C and S

32
Q

PK/PD and half-lives of warfarin

A

anticoagulant effect within 24hrs, peak effect 72-96 hours, duration of action from single dose 2-5 days
hepatically metabolized by CYP450; enantiomer S metabolized by CYP2C9, 2C19, 2C18 and R metabolized by CYP1A2 and CYP3A4 - lots of drug interactions

33
Q

Genetic variances - VKORC1

A

VKORC1 is the reductase enzyme that forms the active form of vit K that then converts vit K into vit K dependent clotting factors
1639A and 1173T: decreased VKOR production
1639A: increased warfarin sensitivity (lower dose needed)
1639G: increased warfarin resistance (higher dose needed)
more 2/3 - more sensitive
more 1/2 - more resistant

34
Q

Who should be tested for warfarin?

A

3 requirements need to be met:
1. patient is warfarin naive
2. genetic test results are available before teh 6th dose
3. pt is at a high risk of bleeding if INR is elevated
if a single one is not met, do NOT offer warfarin genetic testing

35
Q

Warfarin drug interactions

A

increase INR: erythromycin, metronidazole, amiodarone, alcohol, anabolic steroids, fluconazole, isoniazid, ciprofloxacin, bactrim, propafenone, liver disease
decrease INR: rifampin, cholestyramine, carbamazepine

36
Q

Food drug interactions

A

vit K reverses warfarin activity
consistency is key

37
Q

Alcohol and warfarin

A

acute EtOH: increase anticoagulant effect of warfarin by inhibiting its metabolism (increase INR)
chronic EtOH w/o liver damage: enhances warfarin metabolism by inducing hepatic enzymes –> decreases the effect of warfarin (decrease INR)
chronic EtOH w/ liver damage: due to lack of hepatic enzymes, increased anticoagulant effect (increase INR)

38
Q

Antiplatelet use in VTE

A

limited role in VTE
ASA: consideration for CHA2-DS-VASc score 1
dipyridamole: consider concomitant use with warfarin with prosthetic heart valves
concomitant use with anticoagulants and increased risk of bleeding

39
Q

VTE bleeding management

A

discontinue med, apply manual compression, maintain BP, surgical or radiological intervention, blood products +/- PCC +/- antidotes
consider: activated charcoal </= 2hrs of bleeding; hemodialysis - dabigatran only; tranexamic acid
targeted reversal: UFH, LMWH - protamin sulfate; dabigatran - idacruzimab; factor Xa inhibitors - andexanet alfa

40
Q

Protamine sulfate: UFH and LMWH antidote

A

protamine sulfate binds UFH and LMWH to inhibit their further ability to cause anticoagulation
AEs: hypotension, bradycardia

41
Q

Idacruzimab

A

MOA: direct binder to dabigatran (higher affinity than dabigatran to thrombin)
ADR: delirium, HA, hypokalemia, constipation, pneumonia, fever
monitoring schedule: baseline aPTT –> repeat in 2 hours –> every 12 hours until normal

42
Q

Andexanet alfa

A

MOA: binds and sequesters FXa inhibitors
need to consider when last dose of those meds was given and what the last dose was to determine if we use the low or high dose
ADR: local site indusion rxn, DVT, ischemic stroke, AMI, PE, UTI, pnuemonia
no specific monitoring parameters

43
Q

Warfarin: bleeding management

A

dependent on INR and presence/absence of bleeding
vit K, fresh frozen plasma, prothrombin complex concentrate
INR 4.5-10 + NO evidence of bleeding: avoid vit K
INR > 10 + NO evidence of bleeding: PO vit K
major bleeding: PCC preferred over FFP

44
Q

Warfarin reversal

A

rapid (complete): PCC
fast (partial): FFP
prompt: IV vit K
slow: PO vit K
very slow: omit warfarin (no vit K)

45
Q

VTE prophylaxis

A

without prophylaxis: VTE incidence 5-15% in medical pts
without prophylaxis: VTE incidence 40-80% in surgical pts
VTE prophylaxis options: UFH, LMWH, factor Xa inhibitors, vit K antagonists

46
Q

Risk stratification - low risk < 10%

A

minor surgery
fully ambulatory medical pts
no specific pharmacologic therapy recommended
early and aggressive ambulation

47
Q

Risk stratification - moderate 10-40%

A

most non-orthopedic surgery pts
acutely ill medical pts

48
Q

Risk stratification - high 40-80%

A

major orthopedic surgery
major trauma
spinal cord injury

49
Q

Moderate VTE risk treatment

A

general surgery pts: UFH, LMWH, and factor Xa inhibitor recommended; continue prophylaxis up to 28 days after hospital discharge
acutely ill medical pts: UFH, LMWH, fondaparinux, rivaroxaban, betrixaban all apprpriate; UFH, LMWH, and fondaparinux have no specific recommendations for post discharge VTE prophylaxis duration

50
Q

High VTE risk treatment

A

orthopedic surgery (hip/knee replacement pts) - LMWH, fondaparinux, rivaroxaban, apixaban, dabigatran (hip), UFH or vit K
continue >/= 10-14 days postop

51
Q

High bleeding risk

A

mechanical prophylaxis preferred: intermittent pneumatic compression devices, venous foot pumps, graduated compression stockings

52
Q

CHA2DS-VAS and HAS-BLED

A

afib increases risk of stroke or systemic VTE by 5 fold - anticoagulant therapy reduces risk of stroke and all-cause mortality
CHA2DS2-VAC: risk factors for stroke or systemic VTE
HAS-BLED: risk factors for bleeding

53
Q

Score interpretations

A

CHA2DS2-VAS: >/=2 - oral anticoagulation; 1 - no antithrombotic therapy OR oral anticoagulant OR antiplatelet
HAS-BLED: >/=3 - high risk of bleeding, caution and regular monitoring of pt are recommended

54
Q

CHA2DS2-VASc congestive heart failure score

A

1

55
Q

CHA2DS2-VASc hypertension score

A

1

56
Q

CHA2DS2-VASc age >/= 75 years score

A

2

57
Q

CHA2DS2-VASc diabetes score

A

1

58
Q

CHA2DS2-VASc stroke/TIA score

A

2

59
Q

CHA2DS2-VASc vascular disease score

A

1

60
Q

CHA2DS2-VASc age 65-74 years score

A

1

61
Q

CHA2DS2-VASc female score

A

1

62
Q

HAS-BLED hypertension score

A

1

63
Q

HAS-BLED abnormal renal and liver function score

A

1 point each

64
Q

HAS-BLED stroke score

A

1

65
Q

HAS-BLED bleeding tendency/predisposition score

A

1

66
Q

HAS-BLED labile INRs (if on warfarin) score

A

1

67
Q

HAS-BLED age > 65 years score

A

1

68
Q

HAS-BLED drugs or EtOH score

A

1 or 2

PHRM 844 Module #2 (23 decks)

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