VTE Prophylaxis in Pregnancy (Green Top 2015)
- Maternal deaths from VTE down from 1.56/100,000 to 0.70/100,000 due to prophylaxis
Which women with prior VTE require thrombophilia testing?
- Prior to testing, counsel regarding implications for themselves and family
- Test for AT deficiency if: FHx of VTE and either AT def known in family or a specific thrombophilia has not been detected in the family.
- Test for APL Antibodies if: the prior VTE was unprovoked
Which women without prior VTE require thrombophilia testing?
- Consider testing if: the woman has no personal history or RF’s for VTE but has a FHx of an unprovoked or estrogen-provoked VTE in a 1st degree relative when aged <50.
- i.e. if it will change the risk score from 0 to 2.
Previous VTE Alone (Remember to score any additional factors)
Thrombophilia Alone (Remember to score any additional factors)
A few notes on VTE Treatment in Pregnancy
(see full GTG 2015 guideline for details)
- Do not check D-dimer
- No role for pre-test probability scores as not validated (ie Wells)
- If DVT USS normal but clinical suspicion high, re-scan on days 3 and 7
- No need to scan for PE if DVT already proven by USS
- VQ higher risk of childhood cancer > CTPA.
- CTPA higher risk of maternal breast cancer > VQ.
- Absolute risks of both are very small
- LMWH dose should be calculated on booking weight
- Consider monitor Anti-Xa if weight <50kg or >90kg
- Continue through pregnancy and for 6 weeks postpartum, or for three months – whichever is the longer duration
- If VTE occurs at term, consider UFH infusion
- Stop LMWH at start of labour, or 24 hours prior to a planned delivery,
- Neuroaxial anaesthetic should not be performed until 24 hours after last dose of LMWH, and next dose should not be given until 4 hours after the procedure. The catheter should not be removed within 12 hours after the last dose.