Pulmonary Vascular Disease Flashcards
How to pulmonary embolisms usually occur?
Thrombus forms in the venous system, usually in deep veins of the legs (DVT) and (part/all) embolises to the pulmonary arteries.
Incidence of PE and prognosis?
UK incidence is 60-70 per 100 000
Estimated 1% of all hospital admissions.
Massive PE can be fatal, although minor PE treated with anticoagulation has a very good prognosis.
What are the major risk factors for Thromboembolism?
Recent major trauma
Recent surgery
Cancer
Significant cardiopulmonary disease e.g. MI
Pregnancy
Inherited thrombophilia e.g Factor V Leiden
Pulmonary Embolism - symptoms:
1 - pulmonary embolism to one part of the lung, causing pulmonary infarction to that particular tissue area.
2. several small pulmonary emboli dotted around the lungs
3. massive PE
- Pleuritic chest pain, cough and haemoptysis
- Isolated acute dyspnoea
- Syncope or cardiac arrest (massive PE)
Pulmonary Embolism - signs
1 - pulmonary embolism to one part of the lung, causing pulmonary infarction to that particular tissue area.
2. several small pulmonary emboli dotted around the lungs
3. massive PE
- Pyrexia, pleural rub walking in snow noise(due to inflamed pleura due to inflammation surrounding infarction), stony dullness to percussion at base (pleural effusion - as pleura secrete fluid with pulmonary infarction)
- Tachycardia, tachypnoea, hypoxia - due to v/q (ventilation/perfusion) mismatch
- Tachycardia, hypotension, tachypnoea, hypoxia
PE - Investigations
Full blood count, biochemistry, TnI, blood gases (if hypoxic) Chest X-Ray (routine for chest pain) ECG (routine for chest pain) D-dimer CT Pulmonary Angiogram (CTPA) - can confirm PE V/Q scan - in older days before CTPA Echocardiography Consider CT abdomen and mammography Consider thrombophilia testing
PE - Treatment
Patient arrives hypoxic with symptoms:
Oxygen -1st thing!
Low molecular weight heparin e.g. dalteparin - if suspect PE - get in there whilst investigate!
Confirmed PE:
Olden days gave warfrin, but these days give Direct Oral Anticoagulants (DOAC) to thin blood eg rivaroxaban, apixaban
If severe/lifethreatening, give IV Thrombolysis (Alteplase (rt-PA))
And consider a Pulmonary Embolectomy
PE - Prognosis
Mortality at 30 days varies from 0 to 25% PESI Score (Based on age, sex, comorbidity and physiological parameters)
Where do typical thrombus form?
Veins in legs at valves
What veins would a DVT travel through?
Femoral vein, Illiac vein and IVC
What is virchows triad?
To do with :
Stickyness of blood
How fast it is moving
changes to vessel moving through eg fatty deposits
for example, in major trauma, there may be a hypercoagulable state, but there also may be
statis due to immobility.
What 2 key factors could lead to a thrombus in a pregnant woman?
In the latter stages of pregnancy, there will be venous stasis due to direct compression of the inferior vena cava, but there may also be an increased hypercoagulability due to the hormonal changes that occur in pregnancy.
What happens with pulmonary infarction?
Infarction, tissue necrosis, inflammation, pleural rub, pleural effusion
What is pleural rub a sign of?
tissue inflammation
Before you do investigations, what might you do?
A pre-test probability assesment, 2 types: - basically signs and symptoms etc
Wells Score
Includes symptoms and signs of VTE, previous VTE and risk factors
Revised Geneva Score
Based on risk factors, symptoms and signs (heart rate)
What does a D-dimer test indicate
reflects blood clotting - positive result means potential clot (not as reliable as a negative result) - confirmed with a CTPA
negativ result - no thromboembolism
What does a V/Q scan show?
Ventilation /perfusion ratio - white areas have a mismatch vent/perfusion - could be a sign of a PE
Why would an Echocardiograph be done?
Especially in patients with severe PE to work out the strain on the Right heart strain.
Why would you consider a CT abdomen and mammography or thrombophilia testing
To work out the underlying cause of the thrombus/where is came from
