Thromboembolism in Pregnancy

Question 1

When should VTE be treated?

Answer 1

Any signs or symptoms suggestive of VTE → objective testing and treatment with LMWH

Question 2

What is the aetiology of VTE in pregnancy?

Answer 2

• Pregnancy tilts you into a pro-coagulant state
  
  • Higher: F7, F8, VWF, PAI-1, PAI-2, fibrinogen
  • Lower: Protein S
• Virchow’s triad – endothelial injury, hypercoagulable state, stasis

Question 3

What are the signs and symptoms of DVT?

Answer 3

• Red, hot, swollen tender calf
• Unilateral lower limb oedema
• Erythema
• Tenderness
• Low grade pyrexia

Question 4

What are the signs and symptoms of PE?

Answer 4

• Pleuritic chest pain
• Dyspnoea
• Cough
• Haemoptysis
• Tachycardia
• Tachypnoea
• Low-grade pyrexia
• Reduced O2 saturations
• Cardiorespiratory collapse
• Chest signs - reduced air entry, crepitations
• Loud P2 sound

Question 5

What are the the appropriate investigations for suspected DVT?

Answer 5

Duplex USS

Question 6

What investigation normally done for VTE should not be done in pregnancy?

Answer 6

• D-dimer
  
  • Naturally elevated in pregnancy so cannot be used to exclude

Question 7

What are the appropriate investigations for suspected PE in pregnancy?

Answer 7

• General
  
  • ABG = hypoxia or hypercapnia
  • ECG = sinus tachycardia or S1Q3T3
• Imaging
  
  • CXR
  • Duplex USS
  • If both negative → do V/Q or CTPA
    
    • CTPA (higher breast dose) > V/Q scan (higher baby dose)
• Bloods – before anticoagulation
  
  • FBC
  • U&Es
  • LFTs
  • Clotting

Question 8

What is the immediate management of DVT in pregnancy?

Answer 8

• LMWH + elevate leg and apply graduated elastic stockings
  
  • Monitor treatment with anti-Xa levels in women of extreme weight (<50kg, >90kg) or if complicating factors (i.e. renal impairment or recurrent VTE)
• Compression duplex ultrasound if clinical suspicion of DVT
  
  • If -ve and low clinical suspicion → stop anticoagulants
  • If -ve and high clinical suspicion → stop anticoagulants and repeat USS on days 3 and 7

Question 9

What is the immediate management of a minor PE in pregnancy?

Answer 9

• LMWH (SC, BD, 1mg/kg; i.e. enoxaparin)
• ECG + CXR
  
  • If CXR abnormal and clinical suspicion of PE → CTPA
    
    • Suspected DVT + PE → compression duplex USS
    • If no DVT suspected with PE → VQ scan or CTPA
• Repeat testing if VQ scan and CTPA normal, but clinical suspicion of PE remains
• Anticoagulant treatment should be continued until PE is definitively excluded

Question 10

What is the immediate management of a massive PE in pregnancy?

Answer 10

• 1st line = IV unfractionated heparin (monitor with APTT)
• 2nd line = thrombolytic therapy, thoracotomy or surgical embolectomy

Question 11

Which sinus is most commonly affected in central venous sinus thrombosis in pregnancy?

Answer 11

Sagittal sinus

Question 12

What are the signs and symptoms of central venous sinus thrombosis?

Answer 12

• Headache
• Varying neurology

Question 13

What are the appropriate investigations for suspected central venous sinus thrombosis?

Answer 13

MRI

• CT can be first done to exclude stroke etc

Question 14

What is the management of a central venous sinus thrombosis in pregnancy?

Answer 14

• IV unfractionated heparin → thrombolysis → 3-6m anticoagulation

Question 15

What is the maintenance management of VTE in pregnancy?

Answer 15

• Subcutaneous LMWH
  
  • Until at least 6 weeks postnatally and/or ≥3 months of treatment
  • Breastfeeding is fine
• 2nd line = oral anticoagulants (requires routine INR monitoring)
• SEs = heparin-induced thrombocytopaenia, heparin allergy

Question 16

How is delivery managed in patients with VTE?

Answer 16

• If VTE at term = IV unfractionated heparin
• If on LMWH maintenance treatment = no more injections if they go into labour
  
  • If delivery is planned, LMWH should be discontinued 24 hours before
• Anaesthetics
  
  • Epidural not given until at ≥24 hours after last dose of LMWH
  • LMWH not be given until 4 hours after epidural catheter removal

Question 17

How is VTE prevented in at risk patients?

Answer 17

• Prevention at 12w booking
  
  • Prolonged use of LMWH (>12 weeks)
  • Graduated elastic compression stockings
• LMWH + stockings will be based on
  
  • ≥4 risk factors or VTE event = 12w until 10 days to 6 weeks post-partum
  • 3 risk factors = 28w until 10 days post-partum
  • <3 risk factors = conservative