OnlineMedEd: Pulmonology - "Pulmonary Embolism" Flashcards
Review Virchow’s triad.
- Stasis
- Endothelial injury (e.g., surgery, catheter insertion, smoking)
- Hypercoagulable state (e.g., estrogen use)
What is Hamand’s sign?
Calf tenderness
This has been demonstrated to be a poor predictor of DVT.
Why does pulmonary embolism cause pleuritic chest pain?
The clot induces a wedge-shaped infarction of the lung which causes necrosis of the visceral pleura. Breathing rubs the infarcted pleura.
____________ is diffusion limited.
____________ is perfusion limited.
Oxygen
CO2
How do pulmonary embolisms cause diffusion defects?
Platelet-derived factors cause inflammation around the pulmonary vessels that leads to an increased distance from the alveoli to the blood.
The ____________ criteria are used to calculate the probability of a PE.
Well’s
Why should you only get a D-dimer when the pre-test probability is high (greater than 4 on the Well’s criteria)?
D-dimers can be elevated due to many other things –inflammatory states, illness, etc.
The best scan for evaluating pulmonary embolisms is _________________.
CT scan with contrast
Note: pulmonary angiogram is actually better technically, but because it is invasive and takes longer you don’t actually do it in practice.
In the acute treatment of pulmonary embolisms, ______________ should be given.
heparin (or enoxeparin) and then warfarin
_________ should only be given in life-threatening PEs (indicated by hypotension).
tPA