Pre-eclampsia Tutorial

Question 1

How do you diagnose Pre-eclampsia?

Answer 1

·New onset hypertension- SBP ≥140 mmHg and/or DBP ≥90 mmHg

Occurring after 20 weeks’ gestation

·Reduced fetal movement and/or amniotic fluid volume (by ultrasound) in 30% cases

Severe PE: SBP - 160 and DBP- 110

Question 2

What are the other symptoms of pre-eclampsia that can be used to diagnose it

Answer 2

• Oedema common but not discriminatory for PE
• Proteinuria
• Abdominal pain (RUQ or epigastric)

Severe PE

• Stroke·
• Visual disturbances, seizures and breathlessness and risk of eclampsia (seizures)
• HELLP syndrome

Symptoms vary across women

Question 3

what are the subtypes of Pre-eclampsia

Answer 3

Early onset: lower than 34 weeks

• Associated with fetal and maternal symptoms
• Changes in placental structure

·Late onset: occurs after 34 weeks

• More common (90%)
• Mostly maternal symptoms as the placenta relases factors that affect the endothelium (angiogenic factors)
• Fetus is OK
• Less overt/no placental changes

Question 4

what are the maternal risk factors that pre-dispose to PE

Answer 4

Previous pregnancy with pre-eclampsia

BMI >30 (esp >35)

Family history

Increased maternal age (>40, <20?)

Gestational hypertension or previous hypertension

·Pre-existing conditions: diabetes, PCOS, renal disease, subfertility, autoimmune disease.

Non-natural cycle IVF?- when embryo isn’t implanted in mother’s natural cycle

Question 5

What are the risks of pre-eclampsia to the mother and fetus

Answer 5

Mother:

• damage to kidneys, liver, brain and other organ systems
• Possible eclampsia (seizures, loss of consciousness)
• Placental abruption (separation of the placenta from the endometrium)

Fetus:

• reduced fetal growth
• preterm birth
• pregnancy loss/stillbirth

Question 6

what are the placental defects underpinning Preeclampsia

Answer 6

EVT invasion of maternal spiral artey is limited to decidual layer

Spiral arteries are not remodelled; hence low capacity and high resistance. Perfusion tom placenta is restricted

Hypoperfused placenta release pro-inflam proteins. This causes maternal endothelial dysfunction like vasoconstriction or increased permeability

Question 7

what 2 molecules are key that can lead to the maternal symptoms of preeclampsia

Answer 7

Placental Growth factor (PLGF): pro-angiogenic factor released by placenta

Flt-1 (soluble VEGFR1) - soluble receptor for VEG-like factors that binds to soluble angiogenic factors to limit it’s bioavailability.

In PE- the hypoperfused placenta makes too much Flt-1 and hence there’s less proangiogenic factors.

This leads to endothelial dysfunction

Question 8

What are the ways of predicitng PE by using the molecules involved?

Answer 8

PLGR levels

sFlt-1/PLGF

Question 9

what parametes of PLGR can be used to predict Pre-eclampsia

what risk does it increase/interprete the figures

Answer 9

Question 10

How can you use sFlt-1/PLGF ratio to predict/diagnose PE

Answer 10

From 24-36wks (+ 6 days)

More than 38 increases riks of preeclampsia

Question 11

How can you manage pre-eclampsia?

Answer 11

Only be resolved by delivering baby and placenta.

However it depends on gestational weeks:

• If <34 weeks, try to maintain pregnancy
• If >37 weeks, delivery preferable
• In between – case by case basis.

other therapies:

• Anti-hypertensive
• Corticosteroids for ealry onset PE- helps to promote lung development before delivery
• Mitigate end organ damage - give supplemental O2

Question 12

what are the ways of preventing PE?

what about hiogh risk group?

Answer 12

Weight loss (esp if BMI >35)

Exercise throughout pregnancy (seems to work independent of BMI)

Low-dose asprin (from 11-14 weeks) for high risk groups – but may only prevent early onset

Question 13

what are the long term impacts of PE on maternal health

Answer 13

·Elevated risk of CVD, type 2 diabetes and renal disease after PE

·Roughly 1/8 risk of having pre-eclampsia in next pregnancy (greater if early onset)

Question 14

explain the effects of PE induced vasospasms in the:

Kidney

Retina

liver

Answer 14

Kidney- less blood flow (oliguria) and damage it which leads to proteinuria.

Retina-

• bliurred vision,
• sensation of seeing flashing lights
• scotoma- blurry spot in one spot of visual field

Liver

• Increased ALP and GGT (LFTs)
• Stretches liver capsules

Question 15

what is the effect of thrombi formation and increased endotheilal permeability (respectively) due to it’s inury in PE

Answer 15

Thrombus- HELLP

Permeability- fluid leak out leading to:

• Generalized edema
• Pulmonary edema
• Cerebral edema- seizures- eclampsia