VTE in pregnancy Flashcards
Overall incidence of PE in pregnancy and puerperium
1-2 per 1000
1.3 per 10,000 antenatally
Increase in risk of VTE in pregnnacy and postpartum
4-6 fold increase
21-84 fold increase compared to non-preg, 5 fold pregnant rate
Treatment dose tinzaparin
175units/kg
Treatment dose dalteparin
<50kg: 5000units BD
50-69kg: 6000units BD
70-89kg: 8000units BD
90-109kg: 10,000units BD
110-125kg: 12,000 units BD
>125kg = d/w haem
OD dosing double BD dose
Increased risk of VTE if BMI >30
PE: OR = 14.9
DVT: OR = 4.4
Increased risk of VTE whilst in hospital
18 fold increase
Increased risk of VTE when discharged from hospital
6 fold higher for 28 days
Risk of VTE in IVF pregnancy
Overall
1st trimester
Overall: 2x higher
T1: VTE 4x higher, PE 7x higher
Recurrence rate of VTE in pregnancy
11% during pregnancy
3% post pregnancy
Thromboprophylaxis if single previous VTE
At least post-partum LMWH
Anti-thrombin deficiency and previous VTE tx
High risk of recurrence
Give higher dose LMWH (up to tx dose) and continue until 6/52 PP or PO anticoag restarted
Consider anti-Xa monitoring (target 0.5 – 1.0 iu/ml at 4 hours post-dose) and anti-thrombin replacement at initiation of labour or prior to CS
APS and previous VTE - risk and management
High risk of recurrence
Give higher dose LMWH (up to tx dose) and continue until 6/52 PP or PO anticoag restarted
High risk thrombophilias
What are they?
Management
Antithrombin deficiency
Protein C or S deficiency
Compound or homozygous for low-risk thrombophilia
Consider antenatal LMWH
Recommend post-partum LMWH for 6 weeks
Use standard prophylactic dose except anti-thrombin deficiency where intermediate dose may be required
Lower risk thrombophilias
What are they?
Management?
Heterozygous for factor V Leiden or prothrombin G20210A mutations
Antiphospholipid antibodies
Counts as 1x minor VTE risk factorM
Major VTE risk factors postnatal
Any previous VTE
Anyone requiring antenatal LMWH
High-risk thrombophilia (antithrombin deficiency, protein C or S deficiency, compound or homozygous for low-risk thrombophilia)
Low-risk thrombophilia (heterozygous for factor V Leiden or prothrombin G20210A mutations, antiphospholipid antibodies) + FHx of VTE
Tx = 6 weeks LMWH