Risk factors
Virchow's triad
Venous stasis
Endothelial injury
Hypercoagulability
Hx of
DVT
PE
Malignancy
Patients with ovarian or colon cancers are at higher risk for developing PE
Up to 30% of patients who die of ovarian cancer have PE
Patients with esophageal and laryngeal cancer are at lower risk for developing PE
Chemotherapy increases risk of developing PE
Recent surgery
Immobilization
Hypertension
Obesity
Estrogen replacement therapy
Oral contraceptives
Autoimmune diseases
Hematologic abnormalities such as
Factor V Leiden deficiency
Protein C or S deficiency
Antithrombin III deficiency
Homocysteinuria
Epidemiology
Found in about half of patients who have DVT but who do not have symptoms of PE
Pulseless electrical activity in Emergency Department cardiac arrest victims is associated with PE in 33% of cases
Sx
Up to 2/3 of patients with PE have no symptoms of DVT
Dyspnea
Pleuritic chest pain
Apprehension
Cough
Hemoptysis
Sweating
Syncope
Workup
Development of PE without any identifiable risk factors warrants a search for an underlying malignancy
Dx
Diagnosis is made
1. If DVT is demonstrated by duplex US, venography, CT, MRI or some other technique
2. If V/Q scan is convincingly positive
3. If pulmonary angiography, spiral CT or another convincing test is positive
EKG, classic finding
New RBBB
Sinus tachycardia
Right axis deviation
EKG
Tachycardia and non-specific ST-segment and T-wave abnormalities are the most common findings on EKG of patients with PE
Up to 25% of patients will have EKGs unchanged from their baselines
An S1-Q3-T3 pattern is suggestive, but does not indicate pulmonary infarction or severity of PE
