Pulmonary Venous Embolism Flashcards
What is PE?
a common, serious, and potentially fatal complication of thrombus formation within the deep venous circulation
PE is the ______ leading cause of death amount hospitalized patients
3rd
Less than ______% of patients with fatal emboli have received specific treatment for the condition.
10%
What is a common embolus?
Thrombus, but many substances can embolize
What are the risk factors for thrombus formation/PE within the venous circulation?
- Venous stasis
- Injury to vessel wall
- Hypercoagulability (Virchow triad)
- Inherited gene defects
When diagnosing PE, patients typically have one or more of the following:
- dyspnea
- chest pain
- hemoptysis
- syncope
What are some essentials for diagnosis of PE?
- predisposition (usually LE)
- dyspnea, chest pain, hemoptysis, syncope
- tachypnea with a widened alveolar-arterial PO2 diff
- Elevated rapid D-dimer and characteristic defects on CT arteriogram, ventilation-perfusion lung scan, or pulmonary angiogram
Where do thrombi arise?
can arise anywhere in venous circulation or heart, but most often originated in the deep veins of the lower extremities
How does venous stasis increase?
Immobility
Hyperviscosity (Polycythemia)
Increased central venous pressures (low cardiac output states, pregnancy)
How does hypercoaguability occur?
- Medication (oral contraceptives, hormonal replacement)
- Disease
- Inherited gene defects
What are the ECG findings on most patients with PE?
- sinus tachycardia and nonspecific ST and T wave changes
- Sometimes P pulmonale, right ventricular hypertrophy, right axis deviation, and right bundle branch block
What are the arterial blood gas findings in most patients with PE? Is it diagnostic?
- Acute respiratory alkalosis due to hyperventilation
- Not well diagnostic
How are plasma levels of D-dimer in patients with PE?
- elevated in the presence of a thrombus (between 300 and 500 ng/mL?)
What is D-dimer?
A degradation product of cross-linked fibrin
What is used as the initial diagnostic study in North America for suspected PE?
Helical CT pulmonary angiography
What are some other options for imaging PE?
- Ventilation perfusion lung scanning
- Venous thrombosis studies
- chest radiography
- pulmonary angiography
- MRI
What are the most common findings on a chest radiograph of a patient with PE?
atelectasis, parenchymal infiltrations, pulmonary effusion
What are some anticoagulation therapies that can be used? What must you consider?
Heparin or low molecular weight heparin
- age, risk factors, likelihood of hemmorhage, preferences
What is some thrombolytic therapy that can be used for PE?
Streptokinae, Urokinase, recombinant tissue plasminogen activator (rt-PA / alteplase)
What are some additional measures that can be taken when treating PE, other than anticoagulants and thrombolytic therapy?
Inferior vena cava filter
Mechanical or surgical extraction of thrombus
When is thrombolytic therapy indicated?
patients at high risk for death in whom the more rapid resolution of thrombus mat be lifesaving
PE is estimated to cause more than ________ death anually.
50,000
True or False: in majority of deaths, PE is not recognised antemortem or death occurs before treatment
True
What is the outlook for patients diagnosed and appropriately treated for PE?
generally good
