Pulmonary Embolism Flashcards
What is the classic presentation of PE?
Pleuritic chest pain, dyspnea and hemoptysis (coughing up blood) only present 11% of time
- dyspnea at rest or with exertion
- pleuritic pain
- cough
- Tachypnea- more common presentation
- tachycardia
- calf or thigh pain
what is virchow’s triad?
- hypercoagulability
- hemodynamic changes (stastis, turbulence)
- endothelial injury/dysfunction
- test to measure product of fibrin degradation (basically a small protein fragment after clot is broken down by fibrinolysis)
- negative result can essentially rule out thrombis (very sensitive but not specific)
- postive result can indicate thrombosis but does not rule out other potential causes
- main use is to exclude thromboembolic disease when probability is low
D-dimer
what EKG changes would you see in pulmonary embolism
- most commonly sinus tachycardia with possible nonspecific ST/T wave changes
- some patients have the classic PE finding: S1Q3T3
- Atrial arrhythmias, RBBB, inferior Q waves and precordial T-wave inversion
Pros
- sensitivity close to 95%
- will also deetect alternative pulmonary abnormalities that may explain the patients symptoms and signs
Cons
- May predispose patients to further unnecessary testing
- exposes patients to radiation
- requires contrast (be aware of renal function)
CT angiography
What is the PERC rule
quick way of ruling out a pulmonar embolism
- if all 8 are present, quick way of ruling out pulmonary embolism
Initial treatment in PE?
Most patients are stable
- start an IV
- give supplemental oxygen
Initial treatment in PE if the patient is unstable?
hypotension
- IV fluids (limit to 500-1000ml if high suspicioin of PE secondary to RV failure)
- pressor support
Respiratory distress
- oxygen; consider intubation if needed
what initial anticoagulant would you start?
Enoxaparin
- unless unstable
- or renal insufficiency
- preferred in pregnancy
- preferred in malignancy
IV unfractionated heparin (aPTT target 1.5-2.5)
- If unstable
- severe renal failure (CrCL < 30)
- massive ileo-femoral dVT
- likely need for reversal of anticoagulation
what criteria can be used to help determine whether a patient can go home?
- PESI score (prediction of mortality)
- hestia score (criteria for outpatient treatment)
Duration of anticoagulant therapy?
- at least 3 months
- if persistent but reversible risk factors may extend anticoagulation for finite period of time (6-12 months after) until risk factor reverse
- if risk factors not reversible- may consider indefinite anticoagulation
How soon to start the anticoagulation in suspicion of pulmonary embolism?
May consider empiric anticoagulation if:
- high suspicion, especially if patient is unstable
- moderate suspicion but diagnostic evaluation is expected to take longer than 4 hours
- low suspicion if diagnostic evaluation is expected to take longer than 24 hours
Otherwise would start anticoagulation on diagnosis
what should be used in a patient with a PE or DVT and high bleeding risk?
IVC filter placement
- once risk resovled then recommendation is for removal of filter and starting anticoagulant therapy
management for very large PEs or unstable patients
expert consultation advised with possiblity for
- Thromoblytic therapy: alteplase is FDA approved for PE
- catheter directed thrombus removal
- embolectomy (emboli removed surgically or using catheter)
