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Flashcards in Venous Thromboembolism Deck (48):
1

what are the most common presentations of venous thrombosis 

  • deep venous thrombosis
  • pulmonary embolism 

2

venous thromboembolism pathogenesis: Virchow's triad 

  1. stasis: alterations in blood flow
  2. vessel wall injury
  3. hypercoagulability 

3

what are some acquired risk factors (chronic conditions) for VTE

  • malignancy
  • antiphospholipid antibody syndrome
  • myeloproliferative disorders  

4

what is a major risk for VTE

previous thrombotic event 

5

what are some acquired risk factors (transient states) for VTE

  • surgery
  • trauma
  • immobilization

6

what are some acquired risk factors (female specific) for VTE

  • pregnancy
  • hormonal contraceptives

7

what are the most common inherited risk factors for VTE

  • Factor V Leiden mutation
  • Prothrombin gene mutation 

8

What is the pretest probablity scoring system for VTE

Wells criteria 

9

clinical presentation of DVT

  • can be asymptomatic
  • affected area may have
    • swelling
    • pain
    • warmth
    • redness or discoloration 
    • palpable cord (thrombosed vein) 

10

homan's sign 

  • positive sign: pain in the calf on forceful and abrupt dorsiflexion of the patient's foot at the ankle when the knee is extended
  • **test has fallen out of favor

11

Name some important criteria in wells scoring 

  • paralysis, orthopeding casting (1 point)
  • bedridden, major surgery (1 point)
  • tenderness (1 point)
  • swelling of entire leg (1 point)
  • calf swelling (1 point)
  • pitting edema (1 point)
  • cancer (1 point)
  • alternative diagnosis more likely than DVT (-2 points) 

12

wells scoring (numbers showing probability) 

  • 3-8 points = high probability
  • 1-2 points = moderate probability
  • -2-0 = low probability 

13

D-dimer in detecting VTE

  • sensitive test but lacks speficity
    • only useful when negative
  • greater than 500 ng/mL in virtually ALL patients with VTE 

14

is contrast venography recommended as initial screening in detecting VTE

  • not recommended as initial screening
  • invasive

15

what is the preferred test in the setting of recurrent DVT

impedance plethysmography

  • measures small changes in electrical resistance that reflect blood volume

16

what is the test of choice in detecting VTE

compression ultrasound

  • detects loss of vein compressibility 
  • noninvasive, inexpensive 

17

list steps you would take after getting a low probability wells criteria score

  1. D-dimer testing
    1. Negative: DVT ruled out
    2. positive: US

18

list steps you would take after getting a moderate or high probability wells criteria score

  1. US
    1. Positive: treat DVT
    2. Negative: D-dimer
      1. Negative: DVT ruled out
      2. Positive: repeat US in one week 

19

treatment of DVT 

  • anticoagulation
    • initial 5-10 days to protect from recurrent thrombosis
    • long term for minimum of 3 months 
  • early ambulation
  • compression stockings

20

causes of superficial thrombophlebitis 

  • venous cath or PICC line
  • spontaneous
  • hypercoagulability 

21

clinical presentation

  • dull pain in region or involved vein
  • induration
  • redness
  • edema of extremity is uncommon 

superficial thrombophlebitis 

22

management of superficial thrombophlebitis 

  • NSAID
  • generally subsides in 1-2 weeks

23

what is the most common cause of pulmonary embolism 

DVT

24

how is PE classified 

  1. hemodynamic stability 
  2. temporal pattern (acute, chronic)
  3. anatomic location (saddle -> sub-segmental) 
  4. symptoms (present or absent) 

25

hemodynamic instability classification 

systolic blood pressure < 90 mmHg

  • **these patients are more likely to die from obstructive shoci 

26

Name the important signs and symptoms of PE 

  • Dyspnea
  • pleuritic pain
  • cough
  • tachypnea
  • tachycardia

27

97% of patients with PE had one or more of what 3 findings 

  • dyspnea
  • pleuritic chest pain
  • tachypnea 

28

modified wells criteria for PE: what count signifies that PE is likely?

  • PE likely: > 4.0
  • PE unlikely < 4.0

29

If you have determined "PE likely" what imaging should be done?

CT pulmonary angiogram 

30

what was the historical "gold standard" to diagnosis PE 

  • pulmonary angiography
    • invasive
    • high IV contrast load 

31

when would a V/Q scan be used to detect a PE? What are the downfalls to it?

  • IV contrast allergy
  • renal dysfunction
  • sensitive but poorly specific (high # of false positives) 

32

classic findings on EKG in PE

  • sinus tachycardia
  • nonspecific ST-segment and T-wave changes
  • S1Q3T3 pattern

33

what is the alternative to sensitive D-dimer testing in patients with a low probability assessment for PE 

PERC rule: PE rule out criteria 

  • if all 8 criteria are fulfilled, no further testing is required 

34

VTE anticoagulants options

  • IV unfractionated heparin (UFH)
  • SQ low molecular weight heparin (LMWH)
  • oral warfarin
  • factor Xa inhibitors
  • oral direct thrombin inhibitors 

35

initial therapy for the majority of patients with VTE

  • SQ LMW heparin
  • SQ fondaparinux (factor Xa inhibitor)

36

initial therapy for the majority of patients with VTE in patients with severe renal failure and in those more likely to require rapid reversal of anticoagulation 

IV UFH (unfractioned heparin) 

37

initial therapy for the majority of patients with VTE in pregnant patients and patients with malignancy 

SQ LMW heparin

38

long term therapy for VTE anticoagulation 

warfarin

39

what drug can be used to reverse anticoagulation after UFH and LMW heparin administration 

protamine 

40

what drug can be used to reverse anticoagulation after warfarin administration 

vitamin K and fresh frozen plasma 

41

what drug can be used to reverse anticoagulation after factor Xa inhibitors administration 

nothing FDA approved 

42

what drug can be used to reverse anticoagulation after direct thrombin inhibitor administration 

idarucizumab (Praxbind)

43

duration of therapy for DVT if first episode 

  • anticoagulation for a minimum of three months 
  • provoked: persistent but reversible risk factors, extend anticoagulation until the risk factor is resolved 

44

duration of therapy for DVT if recurrent episode of unprovoked DVT, in particular those with proximal DVT 

indefinite anticoagulation 

45

alternatives to anticoagulation (i.e. anticoagulation is contraindicated) 

insert an IVC filter 

  • prevents DVt from propagating to lungs

46

function of thrombolytics. When is it used 

  • activates plasminogen to form plasmin, resulting in the accelerated lysis of thrombi
  • used in unstable patients with PE 

47

function of thrombectomy/embolectomy 

mechanical device to remove clots 

48

prophylactic measures to prevent DVT 

  • sequential compression devices (SCD)
  • thromboembolic deterrent hose (TED)
  • low dose SQ UFH or SQ LMW heparin