Exam 13 - Heme38 - Deep Vein Thrombosis

Front 1

Pathogenesis of venous thromboembolism :

VIRCHOW'S TRIAD :
-Alterations in ...
-... injury
-Alterations in the ... of the blood (ie, inherited or acquired hypercoagulable state)

Risk factor for thrombosis can now be identified in over 80 % of patients

Back 1

blood flow (ie, stasis)
Vascular endothelial
constituents

Front 2

Venous Thrombosis :

Most common presentations:
-... of the lower extremity
-... embolism

Causes of venous thrombosis:
-Hereditary
-Acquired

Back 2

Deep vein thrombosis (DVT)
Pulmonary

Front 3

DVT SEQUELLAE:

More than ½ of DVTs result in chronic ... insufficiency

30% recur over 10 years (after anticoagulation is discontinued)

Leads to ..., potentially fatal

4% of PEs evolve chronic thromboembolic pulmonary hypertension

Back 3

venous
PE

Front 4

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Back 4

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Front 5

Incidence rates for DVT and PE ... markedly with age.

Back 5

increase

Front 6

obesity and VTE:

BMI > ... associated with 2 to 2.5-fold increased risk
-Risk higher with BMI >40
-Reasons are unclear - physical factors with body size, coagulation factor changes

Obesity risk adds to impact of other risk factors
-Oral contraceptives: 2-3 --> 10-fold with obesity
-HRT: 2-3 --> 6-fold with obesity

Back 6

30

Front 7

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Back 7

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Front 8

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Back 8

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Front 9

Pregnancy and thrombophilia:

The higher risk of thrombophilia is with ...

Back 9

factor V ligand (homo)

Front 10

FVL combined with ... increases the risk of thrombolytic disease immensely

Back 10

oral estrogen

Front 11

Surgery and Trauma Patient Population:

Typically no underlying clotting disorder

Injury to body tissues, whether by surgery or trauma, ... risk of DVT

Can occur within hours; even during operation

Majority occur within ...-... days of event

Back 11

increases
10-14

Front 12

Acquired and Inherent High Risk Factors:

Non-surgical:
-Obesity, Cancer, Prior ..., Pregnancy, certain medications (birth control), IV line place in large central vein, > 72 hour ICU stay, kidney failure

Surgical:
-Pelvic surgery (gynecology and urology surgery), orthopedic surgery (hip replacement or fracture repair), prolonged ... (long plane flight, 3 or more days in hospital)

Trauma:
-Spinal cord paralysis injury, multiple limb fractures, pelvis/hip socket (acetabulum) injury, use of clotting medications (rVIIa) or transfusions (platelets)

Back 12

DVT/PE
immobilization

Front 13

DIAGNOSIS OF VTE:

Structured clinical assessment
-... factors
-Symptoms and signs
-... diagnosis

Objective testing
-non-invasive
-invasive

Back 13

Risk
Alternative

Front 14

calf swelling of > ... cm suggests higher probability of DVT

Back 14

3

Front 15

OBJECTIVE TESTING FOR DVT:

...
-Sensitivity over 95%, but specificity only 65%
-Test has high ... predictive value

...
-Sensitivity and specificity over 95% for symptomatic proximal DVT

Venography

Back 15

D-dimer
negative
Compression ultrasonography

Front 16

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Back 16

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Front 17

DIAGNOSIS OF PE:

Structured clinical assessment

Objective testing
-... – can tell us if there is a blood clot anywhere
-... angiography (or V/Q)
-MR angiography – not used much

Back 17

D-dimer
CT

Front 18

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Back 18

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Front 19

laboratory tests are useful in the acute setting:

... --> supportive data to help rule out venous thromboembolism

Troponins/BNP --> stratify severity of PE

..., ... --> essential baseline information prior to starting therapy

... workup generally not useful in the acute setting.

Back 19

D-dimer
PT, aPTT
Hypercoagulable

Front 20

Who should be considered for thrombophilia testing:

Patients with unexplained, or ‘...’ thromboembolism

Patients with thromboembolism that is unusually ..., or in an unusual ... (e.g., portal vein thrombosis)

Patients with a striking ... for venous thromboembolism

Screening of asymptomatic individuals is generally not recommended

Back 20

idiopathic
extensive
location
family history

Front 21

What tests should be done:

-Activated protein C resistance, with analysis for ... if positive
-Prothrombin G20210A genotype analysis
-Antithrombin functional assay
-Protein C functional assay
-Protein S functional assay
-Antiphospholipid antibody testing
-... level

Back 21

factor V Leiden
Homocysteine

Front 22

look at slide 49

Back 22

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Front 23

Advantages of LMWH over UFH:

... bioavailability and predictable pharmacokinetics
-VTE treatment using weight-based dosing with no need for laboratory monitoring

... half-life
-twice or once daily subcutaneous dosing

... rate of heparin-induced thrombocytopenia

Back 23

Better
Longer
Lower

Front 24

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Back 24

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Front 25

Anticoagulant Treatment of Venous Thromboembolism:

Initial treatment with adequate doses of ... is important

... can be initiated early

Antithrombotic effect of warfarin requires reduction of ... levels
-this effect requires at least 4 days of treatment and the need for overlap with heparin

DVT can be treated at home with ...

Back 25

heparin
Warfarin
prothrombin
LMWH

Front 26

Duration of Therapy:

First event with reversible or time limited risk factor
-3-6 months at INR 2-3

... VTE, first or second event
-6-12 months at INR 2-3
-Consider indefinite anticoagulation at INR 2-3 weighing recurrence versus bleeding risk

Special Situations - indefinite anticoagulation
- First event with
*... until resolved (consider chronic LMWH)
*... antibody syndrome
*Multiple genetic defects

Back 26

Unprovoked
Cancer
Antiphospholipid

Front 27

Treatment Guidelines:

For patients with first episode DVT and:
-Antiphospholipid antibodies;
-2 or more thrombophilic conditions
--> therapy for 12 months or ...

For patients with first episode DVT and:
-Antithrombin, protein C or protein S deficiency;
-Factor V Leiden or prothrombin G20210A;
-Elevated homocysteine or factor VIII levels --> therapy for ...-... months

Back 27

indefinite
6-12

Front 28

Preventive Strategies:

Mechanical
-Early ...
-Sequential ... devices
-Vena Cava (main abdominal and chest vein) filters – usually not recommended

Chemical
-Heparin
-Low molecular weight heparin
*enoxaparin sodium
*dalteparin sodium
*tinzaparin sodium
-Coumadin

Back 28

ambulation
compression

Front 29

Prevention during pregnancy:

Single VTE/No thrombophilia - ...
single VTE/Thrombophilia - ...
multiple VTE - ...

Back 29

surveillance
LMWH or UFH prophylaxis
LMWH or UFH treatment

Front 30

Coumadin (Warfarin) can NOT be used during ...

Back 30

pregnancy

Front 31

DVT and PE can be prevented without additional risk factors by use of ... strategy

Risk of DVT, PE and death related to PE in high risk patients is significantly reduced using ... strategy

Back 31

preventive
preventive