Pulmonary Embolism (PE) Flashcards
Define Pulmonary Embolism (PE)
Occlusion within the pulmonary arteries, usually due to a blood clot but could also be fat, air and tumour
Pulmonary embolism is when there is an occlusion within the pulmonary arteries.
What are the 4 possibilities that can occlude the arteries
Blood clot – usually breaks off and travels to the lungs
Fat
Air
Tumour
Name some of the risk factors for pulmonary embolism (PE)
Deep vein thrombosis (DVT) – major risk factor
Previous VTE
Active cancer
Recent surgery (within 2-3 months)
Significant period of immobility e.g. hospitalisation
Pregnancy
Combined oral contraceptive pill
What are patients given in hospital if they are deemed at risk of developing a DVT or PE
Given prophylactic treatment with low molecular weight heparin
The development of VTE/PE is due to Virchow’s triad
What are the 3 components of this triad
- Virchow’s triad is three things that contribute to the development of the blood clots
- Venous stasis
- Endothelial injury
- Hypercoagulable state
What are the classic triad of symptoms of pulmonary embolism (PE)
Pleuritic chest pain i.e. sharp pain on deep inspiration
Dyspnoea i.e. SoB
Haemoptysis
Name the signs of right heart strain
Raised JVP
Hypotension
Tricuspid regurgitation
Loud P2 – split second heart sound as elevated pulmonary pressure leads to delay in pulmonary valve closure.
What is the most common sign of pulmonary embolism (PE)
Tachypnoea - low respiratory rate
What is the scoring tool used in determining the likelihood of pulmonary embolism (PE)
Wells score
What is the Wells score that cause PE is likely
Score > 4
What is the Wells score that cause PE is unlikely
Less than or equal to 4
Name some of the components of the Wells Score for PE
An alternative diagnosis is less likely than PE
Heart rate > 100 beats per minute
Immobilisation for more than 3 days or surgery in the previous 4 weeks
Previous DVT/PE
Haemoptysis
Malignancy (on treatment, treated in the last 6 months, or palliative)
If the Wells Score >4
What is the next step of investigating pulmonary embolism (PE)?
CT pulmonary angiogram (CTPA)
If the Wells Score less than or equal to 4
What is the next step of investigating pulmonary embolism (PE)?
d-dimer
only if positive should a patient undergo CT pulmonary angiogram (CTPA)
What is a d-dimer
D-dimer is a fibrin-degradation product, which is created when blood clots are broken down by the fibrinolytic system
If Wells score suggests PE is unlikely (less than or equal to 4)
D-dimer positive.
What is the next investigation for pulmonary embolism (PE)?
CT pulmonary angiogram (CTPA)
CT pulmonary angiogram (CTPA) is used in investigating pulmonary embolism (PE).
What is it and how does it help in investigating PE?
Chest CT scan with an IV contrast
Highlights the pulmonary arteries to demonstrate any blood clots
Not every patient needs a d-dimer to diagnose pulmonary embolism (PE).
In what incidences is a d-dimer needed
Used before CT pulmonary angiogram (CTPA) in patients with a PE unlikely Wells score (< = 4)
What should be started immediately even before the diagnosis of PE is confirmed in patients
Direct acting oral anticoagulants (DOACs) e.g. Apixaban, Rivaroxaban
After initial management, anticoagulant therapy is required to continue for a period of time to prevent future DVT/PE.
What is the duration of this therapy?
3 months – for those with reversible cause
Beyond 3 months (typically 6 months) – if the cause is unclear, recurrent VTE, irreversible cause
3-6 months – active cancer
After initial management, anticoagulant therapy is required to continue for a period of time to prevent future venous thromboembolism (VTE).
What is the duration of this therapy if there is a reversible cause of the VTE
3 months
After initial management, anticoagulant therapy is required to continue for a period of time to prevent future venous thromboembolism (VTE).
What is the duration of this therapy if there is a cause is unclear, recurrent VTE, irreversible cause
Beyond 3 months (typically 6 months)
After initial management, anticoagulant therapy is required to continue for a period of time to prevent future venous thromboembolism (VTE).
What is the duration of this therapy for those with active cancer
6 months
When is thrombolysis the 1st line therapy for managing PE
Massive PE with haemodynamic compromise e.g hypotension
What is a potential side effect of Thrombolysis
Significant risk of bleeding
Thrombolysis is used to treat clots.
How does it work?
Involves injecting a fibrinolytic medication (they break down fibrin) that rapidly dissolves clots
