PIH & Pre-eclampsia Flashcards
Define Pregnancy-induced HTN (PIH)
New HTN without proteinuria/oedema occuring after 20 wks gestation
What readings do you need to define HTN during pregnancy
Systolic >140 OR Diastolic >90
Increase above booking readings of >30 systolic or >15 diastolic
Prognosis of PIH?
Benign, not associated with adverse outcomes (but may progress into pre-eclampsia)
What happens to BP in normal pregnancy?
BP falls in 1st trimester, continues to fall until 20-24wks
After this BP returns to pre-pregnancy levels
What are high-risk groups for HTN during pregnancy?
- Hypertensive disease in previous pregnancies
- Diabetes
- CKD
- Autoimmune disorders (e.g. SLE/Anti-phospholipid syndrome)
Antenatal management of PIH?
- Consider admission to antenatal ward if severe HTN >160/110 until BP is controlled
- Monitor:
- BP + Urinalysis once/twice weekly until BP is controlled, then weekly after that
- Blood (FBC, LFTs, U&Es) weekly
- USS every 2-4 wks to monitor foetal growth, liquor, UA blood flow
- PIGF-based testing (once only) if suspected pre-eclampsia - Medical = Anti-hypertensives
1st line = Oral Labetalol
2nd line = Nifedipine (asthmatics)
Postnatal management of PIH?
Monitor BP daily for first 2 days after birth
Medical:
- Continue use of antihypertensives if required
- If pt was taking methyldopa during pregnancy stop and change to alternative
- Reduce dose if BP falls below 130/80
Arrange F/U with GP 2wks post-discharge if still on medication and review.
Arrange F/U 6-8wks postnatal to ensure HTN is resolved
HTN should resolve within 6wks - if not, consider DDx chronic HTN
Define Pre-eclampsia
New HTN (>140/90) after 20wks pregnancy
Proteinuria
Oedema
High and moderate risk factors for pre-eclampsia?
HIGH risk:
- Hypertensive disease in previous pregnancy
- Diabetes
- Renal disease
- Chronic HTN
- Autoimmune disease (e.g. SLE/Anti-phospholipid syndrome)
MODERATE risk:
- 1st pregnancy (nulliparity)
- Pregnancy interval >10yrs
- Age >40yo
- BMI >35 at booking
- FMH pre-eclampsia
- Multiple pregnancy
How do you prevent Pre-eclampsia?
1 high risk OR 2 moderate risk factors:
Aspirin 75-150mg OD from 12wks gestation until delivery
Measure BP + Urine for proteinuria at EACH antenatal appointment.
Can also use albumin/protein:creatinine ratio if dipstick 1+
Antenatal management of pre-eclampsia?
Admit to antenatal ward if:
- Severe HTN (>160/110)
- Sx of late-stage disease (headache, visual disturbance, epigastric pain, hyperreflexia, impending pulmonary oedema)
- Abnormal LFTs/U&Es
- Haemotological abnormalities (low Pt, DIC)
- Suspected foetal compromise
Monitoring:
- BP every 1-2 days, every day if admitted
- Bloods (FBC, LFTs, U&Es) 2x week
- USS foetus every 2 wks (growth, liquor etc..)
Medical: Anti-hypertensives
1st line = Labetalol
2nd line = Nifedipine (asthmatics)
3rd line = methyldopa
Aim for BP <135/85
Consider IV magnesium sulphate if features of severe pre-eclampsia and birth is planned within 24hrs
Intrapartum management of pre-eclampsia?
Timing: Aim to deliver 37 wks
Earlier if maternal/foetal concerns
- Uncontrolled BP
- SpO2 <90%
- Maternal bloods deteriorate
- Neuro/eclampsia features
- Placental abruption
- Reversed end diastolic flow
Mode: Elective C-section or Induction
If induction:
- Advise to deliver in labour ward with continuous CTG monitoring
- Give analgesia - epidural helps control BP
- AVOID ergometrine
Postnatal management of pre-eclampsia?
Monitoring:
- Observe for at least 24hrs
- Check BP at least 4x a day (while in postnatal ward)
- After discahrge, check BP every 1-2 days for 2 wks until pt is off treatment and HTN has resolved
Medical:
Continue antihypertensive if required
Stop methyldopa within 2 days after birth!!!
Reduce dose if BP falls <130/80
GP F/U at 2 weeks post-discharge if still on antihypertensive for medication review
Post-natal F/U at 6-8wks to ensure HTN has resolved
HTN+proteinuria should resolve within 6wks
How would you counsel a patient with pre-eclampsia?
- Explain the condition:
Pre-eclampsia is when theres a problem with the placenta which is what connects the baby’s blood supply to the mother’s. As a result you get high blood pressure and protein in the urine.
It occurs in around 5% of pregnant women. - Explain the risks:
Most cases of pre-eclampsia are mild and cause no problems at all. However if it is left untreated it can put both the mother and the baby at risk. Baby could be born prematurely, or baby failing to grow as we expect to. You could also develop seizures called ‘eclampsia’ which can be life-threatening for both mother and baby but they are rare. - Explain the management:
The only way to cure pre-eclampsia is to deliver the baby, so you’ll be monitored closely until the baby can be delivered. We will aim to deliver at around 37 wks and this will either be done by induction or C-section.
In the meantime, we’ll give you some medications to lower your blood pressure. I am going to prescribe Labetalol/nifedipine tablets which you’ll need to take once a day until the baby is born.
We will also monitor your BP very closely, take regular blood tests twice a week, and monitor your baby with USS every 2 wks.
If it becomes severe, there is a chance that we may need to deliver before 37wks.
There is also a 15% chance that this problem will recur in future pregnancies and a small risk of future cardiovascular disease (e.g. HTN, stroke)
How do you manage eclampsia?
- ABCDE
- IV magnesium sulphate
IV loading dose 4g over 5-15mins
then IV infusion 1g/hr
Continue infusion for 24hrs after last seizure OR after delivery
If recurrent seizures, give second loading dose and involve anaesthetist
