venous thromboembolism

Question 1

partial or complete occlusion of deep vein by thrombosis

Answer 1

DVT

Question 2

blocking of pulmonary artery by thrombus (usually from popliteal, femoral, iliac veins)

Answer 2

PE

Question 3

risk factors for VTE

Answer 3

age
previous thromboembolism
obesity
pregnancy
postpartum period
malignancy
inherited thrombophilias
OCP
exogenous estrogen tx
immobility, trauma, surgery

Question 4

virchow triad - promote development of thrombosis

Answer 4

stasis
vascular damage
hypercoaguable

Question 5

leg pain or swelling

Answer 5

symptoms of DVT

Question 6

SOB
pleuritic chest pain
cough
tachypnea
rales
tachycardia

Answer 6

symptoms of PE

Question 7

acute leg pain and swelling diff dx

Answer 7

superficial thrombophlebitis (COMMON): erythema, induration, tender superficial vein caused by inflammation and thrombus (long saphenous vein), 20% have DVT
trauma: fracture, muscle tear, unilateral
cellulitis (COMMON): dermis and subq infection via group A strep or s. aureus, risks: chronic edema, minor trauma, dermatosis
dermatitis (COMMON): pruritis, secondary edema, local histamine

Question 8

chronic leg pain and swelling diff dx

Answer 8

chronic venous insufficiency (COMMON): bilateral, bad valves in saphenous veins, +/- hereditary
postphlebitic syndrome: DVT can damage valves causing chronic edema, ulceration
CHF (COMMON): low CO, systemic venous congestion
pretibial myxedema: NON-pitting, hypothryoidism (weight gain, fatigue, cold intolerance)
hypoalbuminemia (malnutrition, liver failure, GI or renal loss of albumin): bilateral, PITTING edema, stimulates Na retention

Question 9

specific for DVT

Answer 9

history of recent surgery or immobilization for more than 3 days in past 4 weeks

Question 10

sensitive for DVT

Answer 10

pitting edema
calf pain
swelling

Question 11

fever think

Answer 11

PE or systemic infection

Question 12

hypotension, pulmonary edema, cyanosis

Answer 12

PE
CHF
dysrhythmia

Question 13

syncope

Answer 13

PE

dysrhythmia

Question 14

SOB, tachypnea and/or chest pain

Answer 14

PE
CHF
dyshrythmia

Question 15

limitations of duplex venous US

Answer 15

operator dependent
can’t distinguish acute vs chronic DVT
can’t detect pelvic or calf DVT well
bad if edema or obese

Question 16

if high risk for DVT based on clincial decision rule but negative U/S follow-up with

Answer 16

D dimer or repeat U/S

4-7 days later, educate about warning signs

Question 17

use clinical decision rule + venous U/S to diagnose

Answer 17

DVT

Question 18

elevated D dimer -fibrin degradation product

Answer 18

increased risk of DVT

Question 19

positive venous U/S rules in DVT if high risk patient
negative D dimer rules out DVT in low risk patient
positive D dimer also rules in DVT if venous U/S normal in high-risk patient

Answer 19

tests for DVT

Question 20

negative D-dimer

Answer 20

doesn’t rule out DVT