Treatment Approach: VTE Prophylaxis and Treatment

Question 1

Why does a clot form to begin with?

Answer 1

virchow’s triad
1.hypercoaguable state
2.circulatory stasis
3.vascular injury

Question 2

hypercoaguable state risk factors

Answer 2

1.malignancy
2.pregnancy
3.inflammatory state
4.factor v leiden (genetic condition)
5.protein c/s defiency
6.oral contraceptives

Question 3

circulatory stasis risk factors

poor blood flow

Answer 3

1.hospitaliztion
2.surgery
3.obesity
4.long distance travel

Question 4

vascular injury risk factors

Answer 4

1.orthopedic surgery
2.trauma
3.venous catheters
4.smoking

Question 5

multiple components risk factors

Answer 5

1. history of VTE
2. age (older = increased risk)

Question 6

VTE prophylaxis treatment goal

have not had a clot yet

Answer 6

prevent VTE from occurring in patients at high risk (usually only hospitalized patients)

Question 7

VTE prophylaxis treatment

Answer 7

low dose anticoagulation AND/OR mechanical prophylaxis

Question 8

how do you select a patient for VTE prophylaxis?

Answer 8

calculate PADUA score for hospitalized patients or inpatient only
1.score < 4: low risk of VTE and doesn’t require thromboprophylaxis
2.score of 4 or more: thromboprophylaxis is recommended for non-pregnant patients w/o contraindications (major bleeding, low platelets) who are over 18 yrs old

Question 9

treatment options: non-pharmacologic

Answer 9

1.ambulation
2.graduated compression stockings
3.sequential compression devices
4.inferior vena cava filter

Question 10

treatment options: pharmacologic

Answer 10

1.heparin (SQ)
2.enoxaparin (SQ)
3.fondaparinux (SQ)
4.rivaroxaban (orthopedic surgery, general inpatients)
5.apixaban (orthopedic surgery)
6.dabigatran (orthopedic surgery)

Question 11

heparin dosing for VTE prophylaxis treatment

Answer 11

5000 units every 8-12 hours

Question 12

enoxaparin dosing for VTE prophylaxis treatment

Answer 12

30 mg twice daily or 40 mg daily

Question 13

recommendation for high risk OUTPATIENTS with khorana score of 2 or more

Answer 13

may be offered thromboprophylaxis with apixaban, rivaroxaban, LMWH, provided there are no significant risk factors for bleeding and no drug interactions

Question 14

recommendation for outpatients with multiple myeloma receiving thalidomide- or lenalidomide-based regimens with chemotherapy and/or dexamethasone

Answer 14

1. should be offered pharmacologic thromboprophylaxis with either aspirin or LMWH for lower-risk patients
2. LMWH for higher-risk patients

Question 15

signs and symptoms of DVT

Answer 15

1. unilateral leg pain and/or swelling and warmth
2. positive homan’s sign (flex foot and feel pain)
3. elevated d-dimer (nonspecific)

Question 16

veins that proximal DVT occur in

closer to heart

Answer 16

1. deep femoral vein
2. superficial femoral vein
3. popliteal vein

2 and 3 most common (70-80%)

Question 17

veins that distal DVT occur in

Answer 17

1. anterior tibial vein
2. peroneal vein
3. posterior tibial vein

20-30% of DVT in these veins

Question 18

provoked vs unprovoked DVT

Answer 18

1. provoked: caused by a known event (virchow’s triad)
2. no identifiable factor causing DVT

Question 19

treatment choices for patients with VTE and no cancer

Answer 19

dabigatran, rivaroxaban, apixaban, or edoxaban

DOACs

Question 20

treatment choices for patients with VTE and no cancers who aren’t treated with DOACs

Answer 20

Vitamin K antagonist therapt (warfarin)

Question 21

treatment choices for patients with unprovoked proximal DVT or PE who are stopping anticoagulant therapy

Answer 21

aspirin if they do not have a contraindication to it to prevent recurrent VTE

Question 22

treatment duration for patients with proximal DVT or PE

Answer 22

3 months of anticoagulant therapy

Question 23

treatment duration for patients with an unprovoked VTE with low-moderate bleeding risk

low-moderate bleeding risk = 0 or 1 risk factor

Answer 23

extended anticoagulant therapy (no scheduled stop date)

Question 24

treatment duration for patients with an unprovoked VTE with high bleeding risk

high bleeding risk = 2 or more risk factors

Answer 24

3 months of anticoagulant therapy

Question 25

treatment duration for patients with DVT of the leg or PE and active cancer

Answer 25

extended anticoagulant therapy (no scheduled stop date)

Question 26

recommendation for patients with acute isolated distal DVT of the leg

Answer 26

serial imaging of the deep veins for 2 weeks unless there are severe symptoms or risk factors for extension, then anticoagulation

Question 27

recommendation for patients with distal DVT managed with anticoagulation

Answer 27

DOACs for 3 months

same anticoagulation for patients with acute proximal DVT

Question 28

recommendation for patients with acute isolated distal DVT of the leg who are managed with serial imaging

Answer 28

no anticoagulation if the thrombus does not extend, suggest anticoagulation if the thrombus extends

Question 29

recommendation for patients with cancer and DVT

initial anticoagulation

Answer 29

LMWH, Unfractionated Heparin, fondaparinux, rivaroxaban, or apixaban. For patients initiating treatment with parenteral anticoagulation, LMWH is preferred over UFH for the initial 5 to 10 day

Question 30

recommendation for patients with cancer and DVT

long term anticoagulation

Answer 30

LMWH, edoxaban, or rivaroxaban for at least
6 months are preferred

Question 31

recommendation for patients with active cancer such as those with metastatic disease or those receiving chemotherapy and DVT

Answer 31

anticoagulation beyond the initial 6 months should be offered

Question 32

signs and symptoms of PE

Answer 32

1. classic triad: dyspnea, pleuritic chest pain, hemoptysis
2. cough
3. tachypnea
4. tachycardia
5. elevated d-dimer

Question 33

PE classification

Answer 33

1.low risk: PE not meeting other criteria
2.intermediate risk: right ventricular strain on echo, positive troponin, positive BNP
3.high risk: systolic < 90 mmHg or decrease of 40 mmHg from baseline, requiring vasopressors, pulseless

Question 34

PE acute treatment based on classification

Answer 34

1.low risk: therapeutic anticoagulation
2.intermediate risk: anticoagulation, thromboectomy, catheter directed thrombolytics, then therapeutic anticoagulation
3.high risk: iv thrombolytics then therapeutic anticoagulation

Question 35

PKPD of alteplase

Answer 35

1.fibrin specificity: non-specific
2.half-life: 5 minutes
3.dosing: bolus followed by infusion

Question 36

PKPD of tenecteplase

Answer 36

1.fibrin specificity: specific to clot bound fibrin
2.half-life: 90-130 minutes
3.dosing: 1 bolus