VTE in Pregnancy Flashcards
Definiton and Aetiology
Pregnancy is a hyper-coagulable state due to increased levels of clotting factors and reduced fibrinolyisis as a protective factor against haemorrhage at delivery.
There is also venous stasis in the lower limbs due to uterine compression of the IVC during pregnancy.
When is the highest risk of a VTE
In the post partum period
How can a VTE present?
Deep vein thrombosis (DVT)
Pulmonary embolism (PE)
Epidemiology and risk factors
History of VTE
Thrombophilia
Immobility or reduced mobility
Obesity: BMI>30
Multiple pregnancy
Caesarean section
Postpartum period
Age: >35
Smoking
Multiparity: ≥3
Pre-eclampsia
IVF
DVT signs
Calf tenderness: localised to the deep venous system distribution
Erythema
Oedema > 3cm difference between symptomatic calf and contra lateral limb - measured 10cm below the tibial tuberosity
Symptoms
Leg pain: typically unilateral
Leg swelling
PE Signs
Tachypnoea
Tachycardia
Hypoxia
Haemoptysis
Hypotension
PE symptoms
Pleuritic chest pain
SOB
Diagnosis
Compression duplex USS
CXR
ECG: evidence of right heart strain
GOLD STANDARD FOR PE: CT pulmonary angiography (CTPA)
- CTPA/VQ scan not required in Px with suspected DVT/PE confirmed on Doppler USS
Treatment
FIRST LINE: LMWH = Continued for >6 weeks postnatally with Tx totalling 3 months
Oral anti-coagulation: Can be switched to warfarin or DOAC following delivery
Thrombolysis, embolectomy, unfractionated heparin: massive PE with haemodynamic instability
Why is LMWH safe during pregnancy?
Efficacy and safety profile. It doesn’t cross the placenta and therefore poses no risk to the fetus.
Prophylaxis
FIRST LINE: LMWH:
= From 28 weeks if there are 3 risk factors
= From first trimester if there are >4 risk factors
= RF should be assessed at booking and postpartum. Prophylaxis continued until 6 weeks postnatally, with temporary pause during labour
SECOND LINE =
- Intermittent pneumatic compression
- Anti-embolic compression stockings
Complications
- Recurrent VTE
- Post-thrombotic syndrome
- Chronic thromboembolic pulmonary hypertension