Gab Kovacs1 and Paula Briggs2
(1)
Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
(2)
Sexual and Reproductive Health, Southport and Ormskirk Hospital, Southport, UK
Definition
Incidence
Aetilogy and Pathogenesis
Clinical Assessment
History
Examination
Investigations
Treatment
Medical
Surgical
Complications
Prognosis
Definition
Hypertension:
Classified as: mild (140/90–149/99)
Moderate (150/100–159/109)
Severe (> 160/110)
Hypertension in pregnancy is present at booking or in the first 20 weeks.
Gestational hypertension presents after 20 weeks.
Pre-eclampsia is gestational hypertension in association with significant proteinuria.
Eclampsia occurs when convulsions are associated with pre eclampsia.
HELLP syndrome is haemolysis, elevated liver enzymes, and a low platelet count.
Incidence
In developed countries, pre-eclampsia and hypertensive diseases in pregnancy occur in about 5 % of births. It is more common in first pregnancies, or a first pregnancy with a new partner. Age (>40) is a risk factor, as is obesity and multiple pregnancy.
Aetilogy and Pathogenesis
Unknown
Clinical Assessment
History
Symptoms include, headaches, visual disturbance, subcostal pain, vomiting and rapid onset oedema.
Examination
Measure BP at least four times a day
Investigations
Mild – FBC, renal function tests, lfts twice a week
Moderate – FBC, renal function tests, lfts three times a week
Severe – test for proteinuria daily. If proteinuria 1+ or more, measure urinary protein:creatinine ratio (significant if > 30 mg/mmol) on a urine sample.
If elevated: measure 24 h urinary protein excretion (significant if > 300 mg)
Treatment
The only certain means of cure is delivery or termination of the pregnancy.
The important decision is when to deliver. This depends on the prognosis for the foetus and whether it is “safer outside the womb than inside the womb”.
Medical
The aim is to control blood pressure
Maintain blood pressure at < 150/80–100
Mild – anti-hypertensive drugs not necessarily indicated
Moderate
· First line therapy is labetolol, methyldopa or nifedipine
· Second line therapy is hydralazine
Severe – Admit to hospital until blood pressure is controlled, consider commencing low dose aspirin and magnesium sulphate to prevent eclampsia
Surgical
Minor
Induction of labour
Major
Caesarean Section
Complications
Life threatening complications include stroke, cortical blindness, myocardial infarction, renal failure, liver failure, and hepatic rupture.
Prognosis
Recovery is usually complete once the baby is delivered unless there are permanent effects of the complications e.g. stroke.