PRE-ECLAMPSIA AND ECLAMPSIA Medication

The management of severe pre-eclampsia is based on careful assessment, stabilisation, continued monitoring and delivery at the Times New Romanl time for the mother and her baby. This means controlling blood pressure and if necessary convulsions.

Senior obstetric and anaesthetic staff and experienced midwives should be involved.

 

 

 

Antihypertensive treatment should be started in women with a systolic blood pressure over 160 mmHg or a diastolic blood pressure over 110 mmHg. In women with other markers of potentially severe disease, treatment can be considered at lower degrees of hypertension.

Labetalol, given orally or intravenously, nifedipine given orally or intravenous hydralazine can be used for the acute management of severe hypertension. In moderate hypertension, treatment may assist prolongation of the pregnancy. Clinicians should use agents with which they are familiar.

Atenolol, angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor-blocking drugs (ARB)and diuretics should be avoided.

Nifedipine should be given orally not sublingually.

Labetalol should be avoided in women with known asthma.

There has been a general consensus that blood pressure greater than 170/110 mmHg requires treatment in the maternal interest. There is, however, a clear rationale supported by the desire to prevent the known risk of vascular damage due to uncontrolled hypertension.

The preferred therapeutic agents are labetalol, nifedipine or hydralazine. Labetalol has the advantage that it can be given initially by mouth in severe hypertension and then, if needed, intravenously. A review has suggested that hydralazine may be less preferable, although the evidence is not strong enough to preclude its use.⁰³⁰¹ There is also a consensus that, if the blood pressure is below 160/100 mmHg, there is no immediate need for antihypertensive therapy. An exception may be if there are markers of potentially more severe disease, such as heavy proteinuria or disordered liver or haematological test results. Since, in this situation, alarming rises in blood pressure may be anticipated, anti-hypertensive treatment at lowerblood pressure levels may be justified.

There is continuing debate concerning women with a blood pressure between 100 mmHg and 110 mmHg diastolic. Maternal treatment is associated with a reduction of severe hypertensive crises and a reduction in the need for further antihypertensive therapy; however, there appears to be a small reduction in infant birth weight. With treatment a prolongation of pregnancy of an average of 15 days is possible as long as there is no other reason to deliver. Methyldopa and labetalol were the most commonly used therapies in the UK.⁹²⁰¹ Methyldopa has been proven safe in long term follow-up of the delivered babies, while some studies have suggested some benefits of labetalol.⁹⁵⁰¹

Doctors should use the drug with which they are familiar.

Atenolol is associated with an increase in fetal growth restriction.

ACE inhibitors and ARBs would appear to be contraindicated because of unacceptable fetal adverse effects.

Diuretics are relatively contraindicated for hypertension and should be reserved for pulmonary oedema.