VTE

Question 1

Greatest RFs for VTE

Answer 1

PRIOR THROMBOEMBOLISM
-recent major surgery
-trauma
-immobilization
-antiphospholipid Abs
-malignancy
-pregnancy (hormones)
-OCPs
-myeloproliferative disorders

endothelial injury –> stasis of BF –> hypercoagulability (above RFs)

Question 2

Factor V Leiden mutation

Answer 2

Factor V can’t be cut up/degraded by activated protein C so it’s unprocessed and increases r/o clot

Question 3

Where do most PEs arise from?

Answer 3

Most PEs arise from thrombi in the proximal veins of the legs (thigh)

Question 4

What % of proximal DVTs embolize? What % of calf DVTs embolize?

Answer 4

50% of proximal DVTs embolize
3-32% of calf DVTs embolize

Question 5

Clinical features of DVT include

Answer 5

-swelling (97%)
-pain (86%)
-localized warmth (72%)
-redness (50%)
*none are very specific

Question 6

DDx of DVT

Answer 6

-ruptured Baker’s cyst
-cellulitis
-muscle tear
-muscle cramp
-muscle hematoma
-superficial thrombophlebitis
-post-thrombotic syndrome

Question 7

Dx test for DVT

Answer 7

D-dimer (byproduct of clot degradation)

very sensitive - will r/o clot if negative
not specific - can increase d/t lots of things

Venography: injection of radiocontrast agent into distal vein “GOLD STANDARD”
-expensive, difficult, painful

Venous US - test of choice
-non-invasive, 95% sensitive and specific for proximal lesions, 70% sensitive for calf veins

Question 8

If you suspect DVT what should you order first

Answer 8

D-dimer
If neg then no clot
If positive then proceed w/ doppler US

Question 9

PE clinical features

Answer 9

-dyspnea (MC)
-pleuritic chest pain
-cough (w/ or w/o sputum that may be blood tinged)
-many have mild sx or are asx

Question 10

Saddle embolism

Answer 10

branches across R & L lung –> VERY serious

Question 11

PE: Dx tests

Answer 11

-CXR: nonspecific findings - atelectasis (collapse of alveoli), effusion, may be normal
-EKG: tachycardia and ST segment changes (ST elevation is rare in PEs), T wave changes
-Troponin: elevated in 30-50% of mod/large PEs (resolve more quickly in PE than MI)
-D-dimer can exclude PE if negative, but can’t confirm if positive
-CTPA (CT pulm angiogram): imaging modality of choice
-V-Q lung scan (ventilation-perfusion): If CTPA is contraindicated, not feasible, or inconclusive

Question 12

WELLS score criteria for DVT/PE management and AC recommendations

Answer 12

-previous PE or DVT
-HR >100
-recent surgery or immobilization
-clinical signs of DVT
-an alternative dx less likely than PE
-hemoptysis
-CA

Question 13

Proximal (popliteal, femoral, iliac) DVT: Tx

Answer 13

• if no CIs, start AC
  -if CI to AC, place an IVC filter (inferior vena cava)

Question 14

Distal (peroneal, posterior/anterior tibial) DVT: Tx

Answer 14

• if at risk for embolization, start AC
  -if at risk for embolization and pt has CI to AC, then do serial US
  -if low risk of embolization, do serial US over 2 weeks

Question 15

CI to AC

Answer 15

-anything to do w/ bleeding (active bleeding, recent hemorrhagic event, etc.)

Question 16

PE: Tx

Answer 16

-supplemental O2 >90% (mechanical ventilation if needed)
-Thrombolytic therapy (tx of choice if life-threatening PE): rt-PA
-if thrombolytics are CI, then surgical or catheter embolectomy

Question 17

Absolute CI to thrombolytic therapy

Answer 17

-active internal bleeding
-stroke in the past 3 mo
-intracranial dz

Question 18

Relative CI to thrombolytic therapy

Answer 18

-major surgery w/in 10 days
-recent organ bx
-recent puncture of a noncompressible vessel
-recent GI bleed
-liver or renal dz
-severe arterial HTN
-severe diabetic retinopathy

Question 19

AC to use and NOT to use if a pregnant pt develops a DVT

Answer 19

DO NOT use warfarin (teratogenic)
Rather use Heparin

Question 20

PE/DVT prophylaxis for low risk pt (no RFs, but hospitalized)

Answer 20

-No AC
-early ambulation
+/- mechanical thromboprophylaxis (pneumatic compression device)

Question 21

PE/DVT prophylaxis for moderate-high risk pt (hospitalized and at least 1 RF)

Answer 21

-LMWH

Question 22

PE/DVT prophylaxis for orthopedic surgery

Answer 22

-LMWH (Lovenox), Fondaparinux, warfarin, ASA, etc (depends on surgeons preference)

Question 23

PE/DVT prophylaxis for GU, neuro, ocular surgery

Answer 23

-often mechanical prophylaxis only