Obstetric Haematology Flashcards
What are the normal changes to blood parameters in pregnancy?
- Red cell mass: 120-130%
- Plasma: 150%
- Iron usage increases
- Folate usage increases
- Factor VIII and vWF: 3-5x
- Fibrinogen: 2x
- Factor VII: 1.5x
- Protein S: 0.5x
- PAI 1 and PAI 2: 5x (hypofibrinolysis)
- Neutrophilia
What are the recommendations for supplements during pregnancy?
- Iron: 60mg (not routine in UK)
- Folic acid: 400mcg
What are the complications of iron deficiency in pregnancy?
- IUGR
- Prematurity
- Post-partum haemorrhage
What are the causes of thrombocytopaenia in pregnancy?
- Physiological (gestational)
- Pre-eclampsia (increased use)
- ITP
- Microangiopathic syndromes
- BM failure or DIC
What platelet levels are necessary for delivery? When do platelet levels return to normal after delivery?
> 50 needed for vaginal birth
70 for epidural use
In gestational thrombocytopaenia: 2-5 days post partum
In pre-eclampsia: on delivery
What is the management of ITP in pregnancy? What re the complications?
It is the cause of 5% of all thrombocytopaenia in pregnancy
Treated with: IV IG, steroids, Anti-D
Complications include foetal bleeding
How does MAHA occur?
Platelets deposited in small blood vessels, causing a reduction in platelets and RBC destruction, causes organ damage.
What are the risk factors for VTE in pregnancy?
High risk:
- Previous VTE
Risks:
- BMI >30
- > 35 years
- Smoker
- Parity >3
- Multiple pregnancy
- Pre-eclampsia
- Family history
How is VTE managed in pregnancy?
NO WARFARIN
TED stockings
High risk:
- Prophylaxis with LMWH
> 4 risks:
- Prophylaxis with LMWH from 12 weeks
3 risks:
- Prophylaxis with LMWH from 28 weeks
2 or fewer risks:
- LMWH only if admitted
What investigations for VTE are safe in pregnancy?
- Doppler
- VQ scan
D-dimer is useless
What are the considerations for prophylactic LMWH and birth?
- Stop for labour, especially if epidural
- Stop 24 hours before for treatment dose
- Stop 12 hours before for prophylactic dose
What are the complications of VTE in pregnancy?
- IUGR
- Miscarriage
- Late foetal death
- PET
What is anti-phospholipid syndrome?
- Recurrent miscarriage plus positive persistent lupus antibody, anticardiolipin
- 10% live birth rate
- 40% with aspirin
What is the definition of PPH?
> 500ml blood loss
Caused by atony and trauma
Instigate MOH protocol
What can precipitate DIC in pregnancy?
- Amniotic fluid embolism
- Placental abruption
- Retained products of conception
- PET
- Sepsis
