Obstetric Haematology

Question 1

VTE prophylaxis indications

Answer 1

Previous VTE unless post surgery
4 or more risks (give throughout)
3 risk factors (from 28 weeks)
High risk thrombophilia

Question 2

High dose VTE thromboprophylaxis

Answer 2

High BMI
AT deficiency

Question 3

Obstetric VTE risk factors

Answer 3

BMI >30
Age >35
Parity >3
Smoker
Varicose veins
Pre-eclampsia
Immobility
Positive FHx unprovoked VTE
Low risk thrombophilia
Twins
IVF

Question 4

Epidural timing post LMWH

Answer 4

Wait 12 hours before insertion or removal
Don’t restart until 4 hours after insertion or removal

Question 5

AT deficiency

Answer 5

All need VTE prophylaxis, enhanced dose
Aim anti-Xa 0.2-0.4
Use anti-Xa reagent without exogenous AT

If VTE
Need treatment dose
Aim anti-Xa 0.5-0.8
If acute VTE give AT concentrate at onset of labour - give 12 hours after LMWH then wait 12 hours for elective c-section
Epidural guided by anti-Xa level

Question 6

Thrombocytopenia - management throughout pregnancy

Answer 6

FBC 4 weekly until 28/40
FBC 2 weekly until 34/40
Weekly thereafter
If plt <50 at any time pred 0.5mg/kg/day
If plt <80 at 34/40 consider pred +/- IVIg
For delivery give platelets regardless
Aim 40 for NVD or ELCS, 80 for epidural

Baby cord blood
Repeat 7-10 days if ITP