Medical problems in pregnancy Flashcards
Palpitations, extra-systoles and systolic murmurs are very common and mostly benign - T or F?
True
Although rare what is the main direct cause of maternal death in the UK?
VTE
Why is pregnancy a pro-thrombotic state ?
Consider virchows triad:
- There is stasis of blood flow in pregnancy due to venous compression by the pregnant uterus
- It is hypercoagulable
- Endothelial/vascular damage occurs due to varicose vein development
What are the reasons why pregnancy is hypercoagulable ?
- Increased levels of factors 7,8,9,10&11
- Increased numbers of platelets
- Decreased levels of factor 11 & antithrombin 3
Regarding VTE risk what should all pregnant women undergo ?
They should all undergo a documented assessment of risk factors for VTE in early pregnancy or pre-pregnancy
What is given as thromboprophylaxis in pregnancy ?
LMWH
Go over the risk factors for VTE antenatally and state what the management is depending on the score they get from the risk assessment
- If score ≥ 4 antenatally, consider thromboprophylaxis from the 1st trimester
- If score = 3 antenatally, consider thromboprophylaxis from 28 weeks
- If score < 3 antenatally, dont offer thromboprophylaxis, they are considered low risk and mobilisation + avoidance of dehydration is only needed
Following the early pregnancy risk assessment for VTE, when do pregnant women recieve another risk assessment ?
Done in the delivery suite to determine if postnatal prophylaxis is required (as slight changes in the risk factors)
If a pregnant women is admitted to the hospital what should be considered ?
VTE thromboprophylaxis (think cause they will be pretty immobile)
What are the risk factors for postnatal VTE and what are the relevent scores in terms of prophylactic management
- If < 2 risk factors (from low risk) then just need early mobilisation & avoidance of dehyrdation
- If ≥ 2 risk factors (from low risk) or an intermediate (3 point) risk factor then at least 10 days of LMWH with consideration to prolonge if persisting or > 3 risk factors
- If any high risk factors (score ≥ 4) then 6 weeks of LMWH given
What is a DVT ?
This is a thrombosis in one of the deep veins of the leg
Which leg is more commonly affected by DVT’s in pregnancy ?
The left (8:1)
What are the symptoms of DVT in pregnancy ?
- Swelling
- Oedema
- Leg pain or discomfort
- Tenderness
- Increased leg temperature
- Lower abdominal pain
- Elevated white cell count
Note that 50% are asymptomatic
How is DVT diagnosed in pregnancy ?
1st line = compression duplex U/S on lower limb
- if U/S is -ve & low level of clinical suspicion then anticoagulation can be stopped
- if U/S is -ve but high level of clinical suspicion then repeat U/S 1/52 before discontinuation of anticoagulation
Note - you treat then investigate in pregnancy
If iliac vein thrombosis is suspected (whole leg swollen + back pain) - consider MRI venography
Is D-dimer used in investigation of DVT in pregnancy ?
No
What is the treatment of DVT in pregnancy ?
- Any women showing signs/symptoms of DVT should have investigations performed asap but treatment should be given immediately with LMWH regardless i.e. TREAT then SEE
- Graduated compression stockings & mobilisation is also encouraged (TED stockings)
How long can TED stockings be used to help treat/prevent DVT?
- They can be used acutely & upto 2 years after DVT. They ae recommended to be worn following one.
- They can also be used to prevent DVT in women who are hospitalised & travelling long distances (immobile) who are at high risk
How long is LMWH treatment continued after DVT in pregnancy?
Continue for 3 months after delivery or 6 months after treatment was started (whichever is longer)
When a women is on anti-coagulation with LMWH what needs to be monitored ?
FBC, clotting, Us & Es, LFTs
Why is heparin used in pregnancy ?
- Doesnt cross the placenta so safe for the fetus
- Very effective in treating DVT & PE
- Less haemorrhagic manifestation than other anti-coagulation options e.g. mortality, HIT (heparin induced thrombocytopenia), osteopenia.
- Has a long duration of action so only needed to be given OD
What are the possible side effects of heparin therapy ?
- Haemorrhage
- Hypersensitivity
- Allergy at injection site
- HIT
- Osteopenia - possibly developing to osteoporosis with prolonged use
How is PE diagnosed in pregnancy ?
1st line = ECG + CXR
- if CXR is normal then 2nd line = bilateral compression duplex dopplers performed, if this confirms DVT then no further investigations needed & PE treatment initiated
- if CXR abnormal + high clinical suspicion of PE then 2nd line = CTPA
- if suspected PE without signs/symptoms of DVT then V/Q or CTPA done
What is the management of PE in pregnancy ?
Anti-coagulation with LMWH until PE excluded
If PE diagnosed then continue anti-coagulation therapy the same as a DVT (if haemodynamically stable)
If massive life-threating PE in pregnancy/puerperium then 1st line = IV unfractionated heparin + urgent ECG & CTPA +/- thrombolysis considered
What is the CXR radiation dose to the fetus ?
Negligable
What are the radiation risks associated with V/Q scan vs CTPA ?
V/Q carriers a higher risk of childhood cancer than CTPA but a CTPA carries a higher risk of breast cancer to the mother
(hence if possible mothers should be involved in decision making process of investigation of PE)
If a pregnant women is on anti-coagulation what should be done prior to labour & delivery?
- Stop LMWH if she presents in labour and stop it theraptutic doses 24hrs prior to planned labours & prophylactic doses 12hrs prior to planned labours
- This is done due to the bleeding risks of labour
Why should women be offered a choice between LMWH & warfarin postnatally for anticoagulation ?
Because both options are safe when breastfedding ==> they should be given a choice
Why is warfarin avoided in pregnancy ?
It is teratogenic - causes miscarriage, neurological problems & stillbirths (if used in weeks 6-12 of pregnancy)
What changes need to be made to hypothryoidism treatment when a women becomes pregnant ?
Minimal changes, the dose of levothyroxine needs to be increased in the 1st trimester and there TFTs should be checked every trimester
How does pregnancy affect hyperthyroidism ?
- There are more changes than with hypothryoidism:
- Hyperthryroidism may get worse in the 1st trimester due to HCG stimulating the thyroid to produce thyroid hormone. This worsening improves in the 2nd & 3rd trimesters
- The condition is linked with pre-term labour, IUGR & thyroid storm
- Beta blockers (propanolol) used in treatment are possibly linked to IUGR
What is the treatment of hyperythyroidism in pregnancy ?
- 1st line = propylthyiouracil (carbimazole 1st line when not pregnant)
- Beta blockers used to control symptoms actuely e.g. palpatations
- TFTs checked every trimester
What is the commonest chronic medical illness to complicate pregnancies ?
Asthma
How does pregnancy affect asthma ?
It may improve, deteriorate or not affect it at all
What are the effects of asthma on pregnancy ?
Most people will experience no effects on their pregnancy, effects are more associated with poorly controlled asthma and the associated hypoxaemia, these effects can include:
- PIH/PET
- Pre-term labour/birth
- LBW
- IUGR
- Neonatal morbidity e.g. TTN, hypoglycaemia, seizures
What is the treatment of asthma in pregnancy ?
Drugs used are the exact same as in non-pregnant
- 1st line = SABA
- 2nd line = SABA + ICS
- 3rd line = SABA + ICS + LTRA
- 4th line = SABA + ICS + LABA +/- LTRA
- 5th line = MART (LABA & ICS) + ICS +/- LTRA + SABA
- 6th line = increasing ICS to high dose steriods
How can pregnancy affect epilepsy?
- There is an increased chance of seizures in the 1st trimester
- 25-30% of patients experience increased seizure frequency
- 54% experience no chance
- Risk of seizures is highest in the postpartum period
What are the reasons for decreased control of epilepsy during pregnancy ?
- Pregnancy itself
- Poor compliance (due to fears of teratogenesis from medications)
- Decreased drug levels due to N&V (preventing them being absorbed) or due to increased volume of distribution & drug clearance
- Lack of sleep towards term & during labour
What are the effects of epilepsy on pregnancy ?
- Fetus relatively resistant to short-term hypoxia (during seizures)
- Major risk factor is teratogenicity of drugs - even women on no treatment have slightly increased risk of malformations
- Also risk of child developing epilepsy (genetics)
What are the teratogenetic risks of anti-convulsant epileptic drugs (AEDs)?
All are teratogenic
- Major malformations include; neural tube defects, orofacial clefts & cardiac defects
- Minor malformations include; dysmorphic features (low ears, broad nasal bridge), hypertelorism (big distance between eyes), hypoplastic nails & distal digits
Which AED is most associated with neural tube defects?
Na valproate
Which AED is most associated with orofacial clefts ?
Phenytoin
Which AED is most associated with cardiac defects ?
Phenytoin & Na valproate
What increases the risk of teratogenicity in epileptic pregnant women ?
Poor control & number of AED’s used
Are benzodiazepines teratogenic ?
No
There is little difference in risk of teratogenicity between different AED’s which one tho is avoided in women of childbearing age ?
Na valproate (this must have the highest risk of teratogenicity)
What is teratogenicity thought to be due to ?
Folate deficiency
Describe the management of epilepsy in pregnancy
Preconception:
- Take folic acid at least 12 weeks prior to conception
Pregnancy:
- Continue folic acid
- Continue current AEDs if well controlled except wean off phenabarbitone due to risks of neonatal withdrawl convulsions
- Detailed fetal U/S @ 18-20 weeks (as normal antenatal care)
- Detailed fetal cardiac scan @ 22 weeks
- Vit K given orally from 34-36 weeks if on enzyme inducers
- Advise shallow baths or showering (risk of drowning if have a seizure during one)
- If taking steroids increase dose if on enzyme inducing AEDs
What is the intrapartum management of women with epilepsy?
- Most have normal delvieries
- LSCS done if having recurrent generalised seizures in late pregnancy/labour
- Continue AEDs during labour
- Offer early epidural to decrease pain& anxiety
- Explain 1-2% fit during labour or 24hrs after delivery
What is the postpartum management of pregnant women with epilepsy?
- Neonate should have IM vit K
- Encourage breastfeeding (AEDs ok in this)
- Advise shallow baths or showering with door unlocked
- Explain risk of SUDEP increased in pregnancy & postnatal period