| What are the virshow's triad in pathogenesis of venous pulmonary embolism (VTE)? | Alteration of blood flow (like stasis)
Vascular endothelial injury
Alterations in blood constituents (hypercoagulable state) |
| What are the risk factors of deep venous thrombosis and pulmonary embolism? | Age >60, cancer and myeloproliferative neoplasm, chemotherapy (bevacizumab, thalidomide), hormonal modulation (estrogen receptors/ exogenous estrogen/ testosterone), heart failure, Immobilization, infection, nephrotic syndrome, obesity, pregnancy |
| What are the inherited causes of pulmonary embolism? | Inherited thrombophilia (factor V leiden mutation, prothrombin gene mutation, protein S and C and Antithrombin deficiency, dysfibrinogenemia) |
| What are the acquired causes of pulmonary embolism? | OCPs with 3rd generation progestins are most important cause of thrombosis in young women (increases within 4 months of using, and decreases 3 months after the cessation)
Contraceptive transdermal patches and rings as well
Immobilization, congestive failure, medications (tamoxifen, bevaczumab, thalidomide...), antiphospholipid antibody syndrome, myeloproliferative disorder, polycythemia vera...)
IBD, nephrotic disease, macroglobulinemia, multiple myeloma leukocytosis, SCA, HIV |
| What are the pt most eligible to get thromboembolism? | 50% inherited thrombophilia associated with presence of an acquired risk factor (surgery, immobilization, OCP) |
| How is the outpatient treatment of PE/DVT? | Most pt with DVT treated without hospitalization / come with excellent prognosis, treated with anticoagulation (acute VTE requires unfractionated heparin, LMWH, fondaparinux, warfarin, or direct oral anticoaugulant (DOAC)) |
| What are the objectives of DVT treatment? | To prevent further clot extension, and acute pulmonary embolism
so pt are treated with anticoagulants if they are symptomatic proximal DVT with a risk of PE |
| What treatment options other than AG are used for treating DVT? | When there is a contraindication for AG, we use inferior vena caval filter (also indicated for pt with recurrent thromboembolism despite AGs, pulmonary HTN or conccurrent pulmonary embolectomy |
| How is the diagnosis of pulmonary embolism? | CT angiography and D dimer test (may be unnecessary for outpatients)
We can use well's criteria score according to risk factors present
A score <2 low proba, between 2 and 6 moderate and >6 high proba
If low or intermediate score we look at D dimer level to get positive or negative result
Then use multidetector CT to see if there is a PE or not to treat it |
| How is PE classified? | acute or chronic
massive or submassive |
| How is prognosis of PE? | MR: 30% if untreated recurrent PE but if dx and treatment with AG 2-8% |
| How is the pathophysiology of PE? | deep venous thrombus of lower extremity (usually) (mostly iliofemoral veins)
50-80% originate below popliteal vein and propagate proximally, or within proximal veins
Most calf vein thrombi resolve spontaneously only 20% go into proximal veins
Thrombus travel to lungs may lodge to bifurcation of pulmonary artery cause hemodynamic compromise
Smaller thrombi may go more distally and cause pleuritic chest pain by initiating inflammatory response |
| What are the percentages of pulmonary infarctions and multiple emboli? | 10% only cause pulmonary infarction in patients with cardiopulmonary disease
lower lobes being involved in majority of cases |
| What are the symptoms of PE? | Dyspnea at rest or with exertion (within seconds or minutes)
Pleuritic pain, cough, >2 pillow orthopnea, calf or thigh pain or swelling, wheezing |
| What does ABG in PE reveal? | Hypoxemia, hypocapnia, respiratory alkalosis
However it and pulse oximetry are of limited diagnostic role |
| What are the EKG findings in PE? | Tachycardia with ST-T wave abnormalities.
S1Q3T3 (s lead I ...)
RBBB (abrupy RV size or hypertrophy with chronic PE)
Right axis deviation and P pulmonale with T wave inversion V1->V4 |
| What is the duration of PE treatment? | depends on risk factors can range from 3 months to lifelong therapy (if transient risk factors or durable ones) |
| What are the prevention measures of PE? | Low dose unfractionated heparin, low molecular weight heparin, warfarin, fondaparinux, DOAG, compression devices and elastic compression stockings.
IMP for bedbound patients and undergoing surgery |
