Pulmonary embolism Flashcards
Pulmonary embolism
- blockage in one of the pulmonary arteries in the lungs.
- caused by blood clots that travel to the lungs from the deep veins in the legs or, rarely from veins in other parts of the body
Pulmonary embolism
-pathophysiology
- block in the pulmonary artery
- increase right ventricle after load
- increased VR afterload
- RV dilatation
- TV insufficiency
- Lower RV output
- Lower systemic BP
Pulmonary embolism
-Virchow’s triad
- endothelial injury - trauma, hypertension…
- venous stasis - atrial fibrillation, long distance travel, venous obstruction…
- hypercoagulation status - sepsis, smoking…
Pulmonary embolism
-symptoms
- dyspnea
- chest pain
- presyncope or syncope
- hemoptysis
Pulmonary embolism
-differential diagnosis
heart failure, acute coronary syndrome, aortic dissection, pneumonia, COPD, asthma acute exacerbation, pericarditis, aortic stenosis…
Pulmonary embolism
-strong risk factors
fracture of lower limb, hospitalization for heart failure or Afib/flutter, hip or knee replacement, trauma, MI, previous VTE, spinal cord injury.
If cause of pulmonary embolism is unknown, think about what disease?
Cancer
Pulmonary embolism
-physical examination
- tachypnea
- rales
- accentuated second heart sound
- tachycardia
- fever
- diaphoresis
- S3 or S4 gallop
- clinical signs and symptoms of thrombophlebitis
- lower extremity edema
- cardiac murmur
- cyanosis
Pulmonary embolism
-ECG
- S1Q3T3
- complete or incomplete RBBB
- atrial arrhythmias
Pulmonary embolism
-blood test
- main one: D- dimer –> elevated more than 3 times
- plasma troponin
- B-type natriuretic peptide or N-terminal (NT): reflects severity of RV dysfunction and hemodynamic compromise in acute PE
- Lactate: marker of imbalance between tissue oxygen supply and demand.
- Serum creatinine–> shows kidney injury, when you give anti-coagulants, you need to check kidney function
- Measure the amount of oxygen and carbon dioxide in your blood. A clot in a lung blood vessel may lower the level of oxygen in the blood.
Pulmonary embolism
-imaging
- CTPA – CT pulmonary angiography –> main one but only show big arteries, “saddle shaped”
- Planar V/Q scan
- Pulmonary angiography
- Transthoracic echocardiography –> not to see embolus, but to check the size of the ventricles
Pulmonary embolism
-pathophysiology
- right ventricular volume overload
- flattened septum
- increased pericardial constraint
- compressed D-shape LV
- left ventricle becomes D shaped
Index for risk assessment of acute PE
PESI index
Pulmonary embolism
-treatment
- Acute phase: correct hypoxemia, supplemental oxygen indicates, anti-coagulation (parenteral or oral)
- Non vitamin K antagonists –> oral coagulants –> need to calculate creatinine clearance before starting it!!!
- Vitamin K antagonists (warfarin) –> young patients start from 10mg, older patients start from 5mg
- analgesic for patients with pain
- assessment of bleeding risk
Pulmonary embolism
-systemic thrombolysis
- best when performed within 48 hours
- can still be useful in patients who had symptoms for 6-12 days
- thrombolytic agents - tPA, streptokinase, urokinase
