Pulmonary Embolism Flashcards
What is the most common cause of PE?
DVT that breaks off and migrates to the lungs
Where do the DVT emboli originate?
Deep veins of the calf
How does emboli propagate?
Via the popliteal and femoral veins
Large thrombi lodge where upon reaching the lung?
The bifurcation of the main pulmonary artery
Smaller thrombi move distally and do what?
They occlude smaller vessels in the lung periphery and thus produce “Pleuritic chest pain”.
What causes Pulmonary infarction?
Obstruction of lobar pulmonary arteries
What is the characteristic sign of Pulmonary Infarction?
Sudden onset of localized pleuritic chest pain
Recurrent pulmonary embolisms present complications, what are they?
Cor pulmonale, pulmonary hypertension, increased RV stain
Alveoli adequately ventilated but not perused are called?
High V/Q units
Alveoli adequately perused but not ventilated are called?
Low V/Q units
What is Massive PE?
hemodynamic instability from RV failure
What is SubMassive PE?
Patients have evidence of RV dysfunction via CT of echo
How do we diagnose PE?
D-dimer test and CT scan
What wells score shows a likely PE?
If greater than 4
What does a negative D dimer test show?
No PE
Upon chest X-ray for a patient with PE, what do we see?
Westermark sign, an area of hypertranslucency. And a wedge shaped area in the right lower lobe
What is the gold standard for PE diagnosis?
Pulmonary angiography
What are advantages of a V/Q scan?
Less radiation, less allergens, and works for people with bad kidneys
When we do an echo what do we look for?
RV enlargement and ofc dilated pulmonary arteries
When a patient is at risk of a DVT, what preventative measure do we take?
The patient is given low dose Heparin 5000 every 8 hours till risk subsides
What anticoagulant do we prescribe to treat VTE? (venous embolism)
LMWH (low molecular weight heparin)
What is the most widely used regimen for VTE treatment?
80 units of unfractionated heparin, followed by 18 units IV infused guided with a PTT
What is the alternative regimen for VTE treatment involving LMWHs?
1mg dose twice daily
What advantages do LMWHs have over UFH?
Subcutaneous admin, no PTT, act longer.
Warfarin is added on top of the regimen, how so?
Started on the first of heparin therapy at a dose of 10mg a day, guided with a PT and INR
What type of heparin do we get a pregnant woman on?
LMWH, without warfarin
When is Thrombolytic therapy indicated
In Massive PE
What is an IVC filter?
A filter placed into the IVC to trap emboli but maintain blood flow
Who are eligible for an IVC filter?
Patients with Acute VTE and an absolute contraindication to anticoagulant therapy
A surgical catheter embolectomy is recommended for who?
Patients of massive PE
