Hypertension in Pregnancy

Question 1

What is the most common cause of Iatrogenic prematurity?

Answer 1

Pre-eclampsia

Question 2

Increase or Decrease during Pregnancy?
- Plasma Volume, CO, SV, HR, PVR?

Answer 2

All increase apart from PVR which decreases

Question 3

What are the definitions of Hypertension in Pregnancy?

Answer 3

≥140/90 mmHg on 2 occasions , 4 hrs apart.

> 160/110 mmHg once.

Question 4

What are the different types of Hypertension occurring in Pregnancy?

Answer 4

Pre-existing / chronic Hypertension.
- Essential
- Secondary

Gestational Hypertension

Pre-eclampsia (PET)

Question 5

When do the different types of Hypertension occur in Pregnancy?

Answer 5

Chronic hypertension more likely in early pregnancy.

GH / PET are diseases of second half of pregnancy.

Question 6

What secondary causes of chronic hypertension should be considered?

Answer 6

Renal / Cardiac, Cushing’s, Conn’s, Phaeochromocytoma.

Question 7

What are some of the risks of having Chronic Hypertension in Pregnancy?

Answer 7

PET (x 2 risk), Fetal growth Restriction (FGR) and Abruption.

Question 8

What can be done to mitigate effects of Chronic Hypertension in early pregnancy?

Answer 8

Discuss alternatives to ACEi / ARB / Thiazide diuretics. Stop within 2 days.

Question 9

How fast should GH resolve after delivery?

Answer 9

Within 6 weeks

Question 10

What features of Pre-eclampsia does GH share.

Answer 10

No features (nausea, seizures or proteinuria), Better outcomes.

Question 11

What percentage of GH progress to pre-eclampsia?

Answer 11

25% progress to PET - it depends on the gestation.

Question 12

How is GH and Chronic Hypertension managed at birth and Postnatally?

Answer 12

Birth usually >37wks (unless poorly controlled hypertension).

Monitor mothers BP daily after birth.
Target BP <140/90 mmHg.
Stop Methyl Dopa within 2 days.
Continue antihypertensives with review 2 wks post natal and 6-8 wks.

Question 13

What is the Definition of Pre-eclampsia?

Answer 13

A Pregnancy-Specific multi-system disorder with unpredictable, variable and widespread manifestations.

Question 14

What happens in Pre-eclampsia?

Answer 14

Diffuse vascular endothelial dysfunction causing widespread circulatory disturbance.

Question 15

Pre-eclampsia until proven otherwise?

Answer 15

Pre-eclampsia is the onset of New Hypertension after 20 wks with significant proteinuria (UPCR >30mg/mmol)
- Presents with Oedema too.

Question 16

What is the Classification of Early PET?

Answer 16

<34 weeks.
- Uncommon
- Assoc w extensive villous and vascular lesions of the placenta.
- Higher risk of foetal and maternal complications than late PET.

Question 17

What is the Classification of Late PET?

Answer 17

≥ 34 weeks,
- Majority of cases (88%)
- Minimal Placental lesions.
- Maternal factors (e.g. metabolic syndrome) have important roles.
- Most cases of eclampsia and maternal death occur in late disease.

Question 18

What is the Pathogenesis of PET?

Answer 18

An injured placenta releases factors into the maternal circulation that induce PET.
R.Factors for an Injured Placenta include Genetic and Environmental components which create conditions leading to defective deep placentation.

Question 19

Severity of PET

Answer 19

The Severity and timing of the anti-angiogenic state, as well as maternal susceptibility, might determine the clinical presentation of pre-eclampsia.

Question 20

What is the overall pathogenesis of PET in stages?

Answer 20

Genetic / Environmental Predisposition.

Stage 1 - Abnormal Placental perfusion (placental ischaemia)

Stage 2 - Maternal Syndrome.
- An anti-angiogenic sate assoc. w endothelial dysfunction.

Question 21

How does endothelial Dysfunction occur in PET?

Answer 21

Abnormal placentation and trophoblast invasion > Failure of normal vascular remodelling.
Spiral arteries fail to adapt (become high capacity + Low resistance vessels) > Placental Ischaemia > Widespread endothelial damage.

Question 22

What does PET do to the Hepatic System?

Answer 22

• Epigastric / RUQ pain.
• Abnormal Liver enzymes, (- ALT > 150 assoc with increased morbidity)
• Hepatic capsule Rupture.
• HELLP syndrome.

Question 23

What is HELLP syndrome?

Answer 23

Haemolysis, Elevated Liver enzymes, Low Platelets.
(High Morbidity / Mortality)

Question 24

What are the Symptoms assoc with PET?

Answer 24

Headache, Visual Disturbance, Epigastric/RUQ pain, Nausea and Vomiting, Rapidly progressive oedema.

Considerable variation in timing, progression and order of symptoms.

Question 25

What are the signs of PET?

Answer 25

• Hypertension.
• Proteinuria.
• Oedema.
• Abdominal Tenderness.
• Disorientation.
• SGA Foetus.
• Intra-uterine Foetal death.
• Hyper-reflexia / Involuntary movements / clonus.

Question 26

What investigations are done in PET?

Answer 26

U&E, Serum Urate, LFTs, FBC.

UPCR

Ultrasound - foetal assessment.

Question 27

What is the goal of management in Pre-eclampsia?

Answer 27

Monitor BP & Treat Hypertension.
Monitor and manage maternal + foetal wellbeing.
Determine optimal time for birth.
Birth management plan.

Question 28

When should women take Anti-platelet agents w/ risk of PET?

Answer 28

High risk - Take 75-150mg Aspirin (daily from 12 wks)
e.g. - Hypertensive disease during last pregnancy.
- CKD
- SLE or antiphospholipid synd.
- T1DM or T2DM
- Chronic HyperT.

Question 29

How does Aspirin Prevent PET?

Answer 29

Inhibits cyclo-oxygenase > Preventing TXA2 synthesis.
(15% reduction in PET)

Question 30

What is the treatment of Chronic HyperT in Pregnancy?

Answer 30

Continue existing antihypertensives unless;
- SBP < 110 or DBP < 70.

Offer Tx to women no on Tx if:
- SBP > 140 or DBP > 90.

Target BP = 135/8.

Question 31

Does controlling BP reduce risk of PET?

Answer 31

NO

Question 32

What drugs are used 1st line in Tx of hypertension during Pregnancy?

Answer 32

Methy Dopa (Centrally acting Alpha agonist)

Labetalol (alpha + Beta antagonist)

Nifedipine SR (Ca channel antagonist).

Question 33

What drugs are used 2nd line in Tx of Hypertension during Pregnancy?

Answer 33

Hydralazine (vasodilator)

Doxazocin (Alpha antagonist) - Not safe for breast feeding.

Question 34

How is the Foetus surveyed in Hypertension?

Answer 34

Foetal movements.

CTG - daily

Ultrasound, Biometry, Amniotic fluid index, Umbilical Artery Doppler.

Question 35

When should you admit a pregnant women to hospital in Hypertension?

Answer 35

SBP ≥ 160 mmHg.
Abnormal Bloods:
- Creatinine > 90 mmol/l
- ALT > 70 IU/litre.
- Platlet count < 150

Others:
Signs of Impending eclampsia.
Signs of Impending PE.
Suspected Foetal compromise.

Question 36

When should baby be delivered in PET?

Answer 36

Only cure for PET is birth.
Most women delivered within 2 wks of diagnosis.

Indications;
- Term Gestation.
- Inability to control BP.
- Deterioration Haematology / Biochemistry.
- Eclampsia.
- Pulm Oedema.
- Placental Abruption.
- Foetal compromise.

Question 37

What is Eclampsia?

Answer 37

Tonic-Clonic (grand mal) seizure occuring with features of pre-eclampsia.

Seizure common before onset of Hypertension / Proteinuria. (> 1/3rd Px)

More common in Teens.

Assoc with Ischaemia / Vasospasm.

Question 38

Management of Eclampsia?

Answer 38

EMERGENCY!
DRABCDE (resus)

Control BP.
Stop / Prevent Seizures.
Fluid Balance.
Delivery of baby!

Question 39

What is the Tx of Acute Hypertension in Eclampsia?

Answer 39

Labetalol 200mg.

Hydralazine 5mg.

Nifedipine 10mg.

Question 40

What is used for Seizure Tx / Prophylaxis in Eclampsia?

Answer 40

MAGNESIUM SULPHATE IV.

4g IV over 5 mins for loading dose.
Maintenance dose 1g/hr.

Administer for 24 hrs following seizure or birth.