Pulmonary Embolism Oct17 M3 Flashcards
PE on CT
big grey clot
PE origin and where usually terminates
thrombosis in deep veins embolizes, ends up in pulmonary arteries
how to choose who to CT for PE
Virchow’s triad (take people who are susceptibe): hypercoagulative state, endothelial injury, abnormal blood flow)
risk factors for PE (endothelial injuries)
trauma, post op, previous VTE
risk factors for PE( stasis)
immobility (post op, CHF, stroke, travel)
obstruction to venous flow (pregnancy, previous VTE, malignancy, anatomy)
risk factors for PE (hypercoagulability)
acquired state: hormones (pregnancy, birth control pill), malignancy, medication, illness
congenital state: mutations
how much lung can compensate for PE and how
can occlude up to 60% of vessels. other vessels will enlarge to compensate
how ventilation and CO2 change after PE
patients increase their minute ventilation (but alv ventilation drops technically if VE constant). clinically low CO2 bc hyperventilate
how PE can affect airways causing bronchoconstriction
results in chemical mediators release (histamine, serotonin, PGs)
cause of hypoxemia that normally accompanies PE
bronchoconstriction at small airways (VQ mismatch)
what might see happened to heart in PE
right ventricle enlarged
symptoms of PE
dyspnea, chest pain (pleuritic), hemoptysis, palpitations, swollen leg, syncope
Well’s clinical probability of PE: what scores for low moderate and high prob
low prob if less than 2
moderate prob if 2 to 6
high prob if 6 or more
well’s score clinical features and score
- signs and symptoms of DVT: 3.0
- HR more than 100: 1.5
- Immobilization for 3+ days: 1.5
- previous PE or DVT: 1.5
- hemoptysis: 1.0
- Cancer: 1.0
- No alternative diagnosis: 3.0
VQ scanning test principle
test for PE. check V and Q ratio. Only helps if coherent results
