Eclamptic seizure or severe pre-eclampsia: call for senior obstetric and anaesthetic help, give magnesium sulphate, control BP, and plan delivery. Magnesium treats and prevents seizures; it is not an antihypertensive.
Severe features
- BP 160/110 or more, persistent
- Severe headache, visual disturbance, epigastric or RUQ pain
- HELLP (haemolysis, high LFTs, low platelets), pulmonary oedema
- Clonus, brisk reflexes, oliguria, rapidly rising protein
Assessment
- BP and urinalysis (protein) with confirmatory PCR or ACR
- FBC, LFTs, U&E, urate, coagulation if severe
- Placental growth factor-based testing to help rule out
- Fetal assessment: CTG, growth scan and dopplers
Gestational hypertension
- BP 140/90 or higher, no proteinuria
- Monitor BP and bloods
- Treat if 140/90 or higher
Pre-eclampsia
- Hypertension plus proteinuria or organ involvement
- Labetalol first line
- Admit, monitor, plan birth
Severe / eclampsia
- BP 160/110, symptoms, HELLP
- Seizure: magnesium sulfate
- Control BP, senior obstetric and anaesthetic help
Management
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1. Control BP
Labetalol (oral or IV), nifedipine, or IV hydralazine to keep BP below 135/85. Avoid ACE inhibitors, ARBs and thiazides in pregnancy.
Labetalol (oral or IV), nifedipine, or IV hydralazine to keep BP below 135/85. Avoid ACE inhibitors, ARBs and thiazides in pregnancy.
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2. Magnesium sulphate
For eclampsia or severe pre-eclampsia: 4 g IV loading over 5 to 15 min, then 1 g/h for 24 h. Watch for toxicity (loss of reflexes, respiratory depression); calcium gluconate is the antidote.
For eclampsia or severe pre-eclampsia: 4 g IV loading over 5 to 15 min, then 1 g/h for 24 h. Watch for toxicity (loss of reflexes, respiratory depression); calcium gluconate is the antidote.
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3. Deliver
Delivery is the only cure. Timing is a senior obstetric decision balancing maternal stability and gestation; give steroids for fetal lung maturity if preterm. Careful fluid balance (restrict to avoid pulmonary oedema).
Delivery is the only cure. Timing is a senior obstetric decision balancing maternal stability and gestation; give steroids for fetal lung maturity if preterm. Careful fluid balance (restrict to avoid pulmonary oedema).
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4. Postpartum
Risk persists and can worsen for days after birth: continue BP monitoring and antihypertensives, and continue magnesium for 24 h after delivery or the last seizure.
Risk persists and can worsen for days after birth: continue BP monitoring and antihypertensives, and continue magnesium for 24 h after delivery or the last seizure.
Eclampsia drill
- Protect the airway, left lateral, oxygen, call for help
- Magnesium sulphate to stop and prevent further seizures
- Control severe hypertension, then expedite delivery
Pitfalls
- Treating magnesium as an antihypertensive
- Fluid overload causing pulmonary oedema
- Stopping monitoring too soon after delivery
- Missing HELLP with a normal BP
MedPrep - www.medprep.uk - Educational revision aid only. Not clinical guidance. Doses are adult examples; check the BNF, current guidelines and local policy, and seek senior advice. Nov 2026