Pre-eclampsia is a disease specifically associated with pregnancy. It
usually occurs in the second half of pregnancy and it is characterized by
hypertension and proteinuria. The presence of pedal oedema or excessive
weight gain may also be a feature of pre-eclampsia.
Blood pressure monitoring every 4 hours together with daily weighing
of the patient are essential in the management of pre-eclampsia alongside
the recommended investigations.
While blood pressure reduction is essential, lowering the blood
pressure below 140/90mmHg may cause foetal distress and should be
avoided.
CAUSES
The cause is unknown but the disease is more commonly associated
with the following:
· Primigravidae
· Maternal age (women <18 or >35 years)
· Multiple pregnancies
· Hydatidiform mole
· Medical disorders e.g. polycystic ovaries, chronic hypertension,
diabetes mellitus, kidney disorders
· First pregnancy with a new partner
· Previous history of pre-eclampsia
· Family history of pre-eclampsia
SYMPTOMS
· Patients with pre-eclampsia are often asymptomatic
· Swollen feet
SIGNS
Mild cases
· Systolic blood pressure between 140 and 159 mmHg
· Diastolic blood pressure between 90 and 109 mmHg
· Proteinuria of 1+ or 2+
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OBSTETRIC CARE AND OBSTETRIC DISORDERS
· Pedal oedema
Severe cases
· Systolic blood pressure 160 mmHg or higher
· Diastolic blood pressure 110 mmHg or higher
· Proteinuria of 3+ or 4+
· Pedal or generalised oedema
INVESTIGATIONS
· FBC
· Serum Uric Acid
· BUE and Creatinine
· Urinalysis and culture
· Liver function tests
· Random blood glucose
· Daily assessment of urine proteins
· Ultrasound scan for close foetal growth monitoring
TREATMENT
Treatment objectives
· To reduce elevated blood pressure, but not less than 140/90mmHg
· To prolong the pregnancy as much as possible to allow the foetus to
grow and mature for delivery
· To prevent foetal distress
· To prevent or treat any complications that may arise
· To prevent eclampsia
Non-pharmacological treatment
· Admit for bed rest if possible
· Encourage patients to lie on their sides to avoid supine hypotension
Pharmacological treatment
(Evidence rating: B)
Mild pre-eclampsia
There is no need for drug treatment of the hypertension unless the BP
rises above 150 mmHg systolic or 100 mmHg diastolic or the patient
becomes symptomatic of imminent eclampsia (see below).
· Methyldopa, oral,
250-500 mg 8 to 12 hourly
· Nifedipine retard, oral,
10-40 mg 12 hourly
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OBSTETRIC CARE AND OBSTETRIC DISORDERS
· Nifedipine slow release, oral,
30-60 mg daily
SEVERE PRE-ECLAMPSIA AND IMMINENT ECLAMPSIA
This is an obstetric emergency and must be treated urgently. Treatment
is the same as that of eclampsia (see below). These cases are best managed
in hospital under the supervision of an obstetrician.
While blood pressure reduction is essential, lowering the blood
pressure below 140/90mmHg may cause foetal distress and should be
avoided.
BP monitoring must be carried out every 15-30 minutes until the BP is
reduced and the patient is stable. Thereafter monitoring can be done by 2-4
hourly.
Daily weighing of the patient is essential.
SYMPTOMS
· Frontal headaches
· Vomiting
· Visual disturbances such as double vision (diplopia), blurred vision,
flashes of light
· Epigastric pain
· Decrease in urine production (oliguria)
SIGNS
· Elevated blood pressure
· Liver tenderness
· Urine production of < 30ml/hour or < 400ml / 24 hours
· Increased tendon reflexes
· Presence of ankle clonus (occasionally)
INVESTIGATIONS
· FBC
· Blood clotting profile (bedside clotting time, prothrombin time, INR,
APTT)
· Serum uric acid
· BUE and Creatinine
· Urinalysis and culture
· Liver function tests
· Random blood glucose
· Daily assessment of urine proteins
· Ultrasound scan for close foetal growth monitoring
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OBSTETRIC CARE AND OBSTETRIC DISORDERS
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TREATMENT
Treatment objectives
· To reduce the blood pressure, but not lower than 140/90 mmHg
· To prevent the mother from suffering from complications of the
hypertension such as a stroke
· To prevent fits/eclampsia
· To stabilise the patient and deliver her if eclampsia is imminent
Non-pharmacological treatment
· Early delivery of mother if eclampsia is imminent
· If the patient is not symptomatic and the pregnancy is less than 34
weeks allow pregnancy to continue if the foetal condition would allow
· If the pregnancy is 34 weeks or more consider delivery after
stabilisation
Pharmacological treatment
(Evidence rating: C)
Pre-hydration (without overloading) with
· Sodium Chloride 0.9%, IV,
Or
Ringer's lactate, IV,
300 ml over 30 minutes
· Hydralazine, IV,
5-10 mg slowly over 20-30 minutes
Or
Nifedipine, sublingual,
10 mg stat
Or
Labetalol, IV,
20 mg stat over at least 1 minute
· Repeat at 10-minute intervals if the BP remains > 160/110 mm Hg as
follows: 40mg; 80mg; 80mg boluses to a cumulative dose of 220 mg
· When the BP < 160/110 mmHg commence an infusion of 40mg per hour.
· Double the infusion rate at 30-minute intervals until satisfactory
response or a dose of 160mg per hour is attained.
Subsequently
· Nifedipine retard, oral,
20-40 mg daily
And/Or
Methyldopa, oral,
250-500 mg 8-12 hourly
OBSTETRIC CARE AND OBSTETRIC DISORDERS
· Magnesium sulphate, IV,
20 ml of the 20% solution (4 g)
And
Magnesium sulphate, IM,
10 ml of the 50% solution, (5 g) into each buttock (total of 10g)
REFER
Refer all cases of severe pre-eclampsia and imminent eclampsia
promptly to a hospital or obstetrician after initiation of treatment.
When the “obstetrician” considers that the foetus is immature, the patient
should be transferred to a hospital capable of looking after the immature
baby.
