Hypertensive disorders (+Pre-eclampsia)

Question 1

What is Gestational / Pregnancy-induced hypertension (PIH)?

Answer 1

Diagnosis of new onset raised blood pressure after 20/40
With NO proteinuria and normal blood values

[25% go on to pre-eclampsia]

Question 2

What is pre-eclampsia?

Answer 2

Multi-system disorder including Raised blood pressure (>140/90mmHg) + Proteinuria (>300mg per 24 hours) after 20/40 gestation. Also now includes
- Thrombocytopenia (Platelets <100),
- Renal involvement (Creatinine >=90),
- Liver involvement (ALT >=40),
- Uteroplacental dysfunction?? (EFW <=10th centile)

[Note, instead of 24 hour urine collection can use Protein:Creatinine ratio (PCR) >=30]

Question 3

Give 4 maternal complications associated with pre-eclampsia

Answer 3

CNS = Eclampsia, Stroke, Cortical blindness
Renal = AKI / Renal tubular acidosis
Liver = HELLP syndrome, Liver rupture
Respiratory = Pulmonary oedema
Haematological = DIC, VTE
Placenta = Placental abruption

Question 4

What are the fetal complications associated with pre-eclampsia? (give 3)

Answer 4

Small for gestational age
Prematurity
Still birth

Question 5

What is the pathophysiology behind pre-eclampsia?

Answer 5

Failed trophoblastic invasion + Failed adaptation of spiral arteries (aka poor placentation)
- Poor placental perfusion and placental “ischaemia” = oxidative stress = endothelial dysfunction
- Maternal responses&raquo_space; High levels of circulating pro-inflammatory cytokines, Endothelial dysfunction, Increased capillary permeability, Releases of vasoconstrictive substances (Eg Thromboxane A2) = increased systemic vascular resistance

Question 6

What is the pathophysiology behind pre-eclampsia?

Answer 6

Failed trophoblastic invasion + Poor adaptation of spiral arteries (aka poor placentation)

Maternal responses:
- High levels of circulating pro-inflammatory cytokines
- Endothelial dysfunction
- Increased capillary permeability (oedema)
- Releases of vasoconstrictive substances (eg Thromboxane A2) = Increased systemic vascular resistance

Question 7

Give 4 risk factors for pre-eclampsia

Answer 7

Hypertensive in previous pregnancy
PMHx of pre-eclampsia
FHx of pre-eclampsia
Diabetes
BMI >35
Chronic kidney disease
Age >=40 years
Primigravida
>10 years since last pregnancy
Multiple pregnancy
Molar pregnancy

Question 8

What are the risk-reduction steps for Pre-eclampsia?

Answer 8

Preconceptual counseling + optimising of pre-existing conditions

Aspirin 150mg daily from 12/40 until 38/40 for those at risk

Dalteparin if antiphospholipid syndrome or other pro-coagulant disorder

Question 9

Give 4 symptoms of pre-eclampsia

Answer 9

Many = asymptomatic
Headache
Visual disturbances
Abdominal pain (RUQ typically)
Oedema (peripheral swelling)
Vomiting
Bleeding
Reduced fetal movements

Question 10

Give 4 signs of pre-eclampsia

Answer 10

Hypertension
Proteinuria
Non-dependent oedema
HYPER-REFLEXIA / Clonus
Fetal growth restirction / Oligohydramnios / Abnormal fetal doppler

Question 11

What are the pre-eclampsia investigations?

Answer 11

Pre-eclampsia investigations:
- Maternal&raquo_space; FBC, U&E + eGFR, LFT, Coagulation profile, PCR (Urinary Protein:Creatinine ratio)

Fetal:
- Growth velocity (fetal growth ultrasound).
- Fetal wellbeing (CTG, Amniotic fluid, Fetal doppler).

Question 12

What is the treatment for pre-eclampsia?

Answer 12

Blood pressure control (aim for 135/85):
- Oral = Labetalol, Nifedipine MR, Methyldopa [second line = Doxazosin]
- Emergency (IV) = Labetalol. Hydralazine.

R.e. BP >=160/110 = Admit and Treat

Management of severe or fulminating pre-eclampsia:
- Control Hypertension
- Prevent Seizures (maternal Magnesium infusion)
- Administer Steroids for lung maturation if preterm
- Deliver by most appropriate route
- Strict fluid balance + HDU care

Question 13

What is the definition for Eclampsia?

Answer 13

Seizures occurring in pregnancy or within 10 days of delivery and with at least two of the following features documented within 24 hours of the seizure:
- Hypertension
- Proteinuria one “plus” or at least 0.3g/24h
- Thrombocytopenia less than 100,000/μl
- Raised transaminases

Question 14

What is the management for Eclampsia?

Answer 14

ABCDE approach
IV access
Bolus of 4g Magnesium Sulphate
Continuous infusion of Magnesium Sulphate
Control hypertension
If antenatal- plan for delivery by most appropriate route
Fluid balance + HDU care

Question 15

What is the term for Hypertension present before 20 weeks of pregnancy?

Answer 15

Chronic hypertension

Question 16

What is the management for Chronic hypertension in pregnancy?

Answer 16

Monitor renal function
Assess need for ECHO (longstanding, CVS morbidity)
Aspirin 150mg from 12 weeks until 36 weeks (prevents pre-eclampsia)
Serial growth scans
BP 2-4 weekly (home monitor)&raquo_space; Control BP
Delivery at 39-40 weeks (in the absence of other complications)

Question 17

What are the criteria for HELLP syndrome?

Answer 17

Haemolysis
Elevated Liver Enzymes
Low Platelets

Occurs in 5% of pre-eclampsia; 10-20% of severe pre-eclampsia
MDT involvement