What is a DVT?
Formation of a thrombus in the deep veins of the leg
What causes a pulmonary embolism?
Part of the thrombus in DVT breaks off, travels in the venous system to the heart -> right atrium -> right ventricle -> pulmonary arteries -> lodges and blocks artery
What can a massive PE cause?
MI
- Blocks flow of blood in RA and RV
What is Virchow’s triad?
Clotting is more likely to happen if…
- Stasis of blood flow
- Endothelial injury
- Hypercoagulability
What are the risk factors for a VTE?
- Active cancer
- Family Hx DVT
- Previous DVT
- Age >60
- Immobility > 3 days
- Major surgery within 12 weeks
- Pregnant or given birth in last 6 weeks
- HRT or OCP
- Obesity
- Inflammatory disorders
- Thrombophilia
What is the physical presentation of a DVT?
• Unilateral • Calf/leg swelling o >3cm compared to unaffected leg • Dilated superficial veins • Tenderness to the calf o Worse with dorsiflexion of the ankle (Homan’s sign) • Oedema • Colour changes in the leg
What are the differentials of DVT?
- Cellulitis
- A ruptured baker’s cyst
- Muscle haematoma
How could you diagnose DVT?
- Medical Hx
- Physical examination
- Well’s score
What do you do if Well’s score is >2 for DVT?
Means DVT likely
- Offer proximal leg vein US
If this cannot be carried out within 4 hours offer:
- D-dimer then
- Interim therapeutic anticoagulation and then
- Proximal leg vein US that is available within 24 hrs
What do you do if Well’s score is <2 for DVT?
Means DVT unlikely
- D-dimer
+ve = proximal leg vein US
-ve = stop interim therapeutic anticoagulation
if results cannot be obtained within 4hrs start interim therapeutic anticoagulation
What is the physical presentation of a PE?
Main 3:
- Dyspnoea
- Pleuritic chest pain
- Haemoptysis
Others:
- Tachypnoea
- Tachyarrhythmias
- DVT signs
What is the physical presentation of a massive PE?
- Syncope
- Arterial hypotension
- Cardiogenic shock/ cardiac arrest
- Restrosternal chest pain
- Cough
- Haemoptysis
What are the differentials of PE?
Respiratory o Pneumothorax o Pneumonia o Acute bronchitis o Acute exacerbation of asthma o Acute exacerbation of COPD o Acute exacerbation of chronic lung disease
CV o ACS o Acute congestive HF o Dissecting or rupturing aortic aneurysm o Pericarditis
Musculoskeletal chest pain
GORD
Other causes for collapse: o Vasovagal syncope o Postural hypotension o Cardiac arrythmias o Seizures o Cerebrovascular disorders o Panic disorder
What do you do if a 2-level Well’s score is >4 for PE?
- CT Pulmonary Angiogram (CTPA)
What would you do if the CTPA is delayed?
- Anticoagulation with DOAC
When would you do a V/Q scan for PE instead of a CTPA?
- Pregnancy
- Allergies to contract
- Creatinine clearance <30
What other investigations for PE would you order?
- U+E
- Clotting screen
- FBC
- LFT
- ABGs
- CXR
- ECG
- Echocardiogram
Only indicated in massive PE
What may an ECG show in PE?
Right heart strains
- Deep S-wave in I
- Q-waves in III
- Inverted T-waves in III
P-pulmonale
- Right atrial enlargement (p-pulmonale)
- Right axis deviation
When would you order an echocardiogram?
When massive PE is suspected
What do you do if a 2-level Well’s score is <4 for PE?
PERC rule
What do you do if a patient is PERC +ve or has a DVT wells score >2 for PE?
D-dimer
- -ve = DVT and PE can be excluded without further testing
- +ve = further imaging must be done
Us doppler scan of leg
CTPAWhat do you do if a patient is PERC -ve and has a DVT wells score <2 for PE?
No further investigations needed
