Thromboembolism in pregnancy Flashcards
What are 2 types of thromboembolism?
DVT: Blood clot in deep veins, usually leg
PE: Distal spread of thrombus into lung
What is the significance of previous VTE in a pregnant woman?
Immediately considered high risk
Start on LMWH
List 9 pre-existing risk factors for VTE in pregnancy
Previous VTE
Thrombophilia
Age > 35
BMI > 30
Parity > 3
Smoker
Gross varicose veins
Immobility
FH of unprovoked VTE
List 6 obstetric risk factors for VTE in pregnancy/ postpartum
Multiple pregnancy
IVF pregnancy
Current pre-eclampsia
C section
Prolonged labour >24h
PPH
Give 3 transient risk factors for VTE in pregnancy/ postpartum
Long haul travel
Admission/ immobility e.g. Pelvic girdle pain
Hyperemesis + dehydration
What criteria indicates initiation of LMWH in pregnancy?
> ,4 RFs: immediate LMWH continued until 6w postnatal.
3 RFs: LMWH from 28w + continued until 6w postnatal
When is the highest risk of VTE in pregnancy?
Postnatal
What is the leading direct cause of maternal mortality in the UK?
PE
Give 4 signs and symptoms of DVT in pregnancy
Leg pain + discomfort (left more common)
Leg swelling, tenderness + oedema
Increased temperature
Raised WCC
Give 5 signs and symptoms of PE in pregnancy
Dyspnoea
Pleuritic chest pain
Haemoptysis
Faintness/ collapse.
+/- Sx or signs of a DVT.
Give 4 measurable signs of PE on examination
Tachypnoea
Raised JVP
ECG changes.
ABG: respiratory alkalosis and hypoxaemia.
How should women with suspected VTE be managed?
Immediate referral to hospital
Start LMWH until dx excluded with imaging
What investigations are required for suspected DVT in pregnancy?
Compression duplex USS
If -ve + low clinical suspicion, anticoagulant Tx can be discontinued.
If -ve + high clinical suspicion, anticoagulant Tx should be discontinued but USS repeated on days 3 + 7
What management other than LMWH can be used in women with DVT?
Leg elevation
Compression stockings
Keep active
What investigations should be performed in suspected PE?
ECG (T wave inversion) + CXR
If also Sx/ signs DVT:
Compression duplex USS. If +ve no further Ix required. Tx should continue
If no Sx/ signs of DVT: CTPA or V/Q scanning
Give 3 advantages of CTPA
More readily available
Lower radiation risk to foetus
Can identify other pathology e.g. pulmonary oedema, pneumonia
What is the main disadvantage of CTPA?
Increased risk maternal breast cancer
What is the main disadvantage of V/Q scanning?
Increased risk of childhood cancer
What test should NOT be performed in VTE in pregnancy?
D-dimer
D-dimer rises progressively through pregnancy with advancing gestation
Are pretest probability scores indicated in VTE in pregnancy?
No evidence to support use of Wells score
(Wells score used in non-pregnant)
What bloods should be taken before initiating anticoagulant therapy?
FBC
Coagulation screen
U+Es
LFTs
What are the risks of LMWH in pregnancy?
heparin does NOT cross the placenta + can’t harm baby
No increased risk of severe PPH
Bruising at site of injection
For what duration must LMWH be taken in pregnancy from VTE event?
For the rest of the pregnancy + >,6w after birth, until at least 3/12 tx has been given in total
How does LMWH affect birth plans?
If go into labour, cannot have epidural if within 24h of last LMWH (but there is alternate pain relief)
If plan is to induce labour/ C section stop LMWH 24h before. LMWH will be restarted within 4h
Emergency CS: GA if last LMWH <24h
What is the aetiology of thromboembolism in pregnancy?
Virchows triad: Injury, stasis, hypercoaguablity.
Commonly deep veins of leg and pelvis and embolises to pulmonary vasculature. Pregnancy is procoagulant.
What are risk factors of thromboembolism in pregnancy?
General: Maternal age, thrombophilia, obesity, personal/FHx, msmoking immobility.
Pregnancy: C-section, instrumental, infection, PREC, multiple, HEG/dehydration.
What is the management of thromboembolism in pregnancy?
Prevent: Movement, evaluate thromboprophylaxis, compression stockings, LMWH.
Treat: LMWH, initiate even only on clinical suspicion. Continue for rest of pregnanct and discontinue on labor initiaiton. Continua 6/52 postnatal.
Massive PE: ABC, MDT management, IV unfracHep. Early thrombolysis, thoracotomy or surgical embolectomy.
