Severe pre-eclampsia with HELLP at 35 weeks in a busy delivery suite
Ms Wong, 32, G2P1, booked at a public hospital, presents at 35+2 weeks with a three-day history of frontal headache and visual blurring. BP is 172/114 mmHg on two readings 15 minutes apart. Urine protein-to-creatinine ratio is 210 mg/mmol (normal <30). Platelets 76 ×10⁹/L, ALT 186 U/L, creatinine 96 µmol/L (baseline 58), urate raised. She has brisk reflexes with three beats of ankle clonus and reports epigastric discomfort. The cardiotocograph shows a baseline of 150 beats/min with normal variability and no decelerations. She takes no regular medication and has had no antenatal antihypertensives. The delivery suite is busy, the on-call anaesthetist is in theatre, and the neonatal unit has one free intensive care cot.
1. Set out your management in the first 60 minutes, including drugs and doses, and justify the timing of delivery.
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This is severe pre-eclampsia with HELLP syndrome; the priorities are seizure prophylaxis, blood pressure control, and delivery after stabilisation.
Call the senior obstetrician, anaesthetist and midwife; position left lateral; start continuous CTG; secure two IV lines and send FBC, coagulation screen, fibrinogen, U&E, LFT, group and save. Give magnesium sulphate 4 g IV over 20 minutes (diluted to 100 mL) then 1 g/hour for 24 hours or until 24 hours postpartum. Lower the BP with labetalol 200 mg orally, or 20 mg IV increments every 10–15 minutes, to a target of about 140–150/90–100 mmHg; hydralazine 5 mg IV is an alternative. Restrict fluids to about 80 mL/hour total.
Delivery is indicated because of severe features plus HELLP at 35 weeks; there is no benefit in expectant management once platelets are falling and liver enzymes are rising. Aim to deliver within 24 hours, and within a few hours if platelets fall below 50 or liver enzymes rise sharply. Antenatal corticosteroids are not routinely indicated at 35 weeks for this indication.
2. The platelets are 76 ×10⁹/L and operative delivery may be needed. How does this change your anaesthetic planning, and what else must you check?
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A platelet count of 76 is generally below the accepted threshold for neuraxial blockade (commonly 75–80 ×10⁹/L, and higher if the count is falling rapidly), because of the risk of spinal or epidural haematoma. I would therefore plan for general anaesthesia if caesarean delivery is required, and I would tell the anaesthetist this early rather than hoping for theatre availability later.
I would also repeat the platelet count, PT/APTT and fibrinogen urgently, since HELLP evolves over hours and a fall to below 50 changes management further. If platelets fall below 50 and surgery is needed, transfuse platelets immediately before incision; below 20, or with bleeding, transfuse regardless. Look for DIC (prolonged PT/APTT, low fibrinogen, schistocytes). Vaginal delivery remains a reasonable option if the fetal tracing stays normal and platelets are stable, but epidural analgesia should not be offered. Document the discussion with the anaesthetist and the woman.
3. What safety monitoring is required during magnesium sulphate infusion, and when would you stop it?
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Magnesium is renally excreted, and her creatinine is already 96 µmol/L, so toxicity risk is increased. Monitor hourly: respiratory rate (stop if <12/min), patellar reflex (loss is an early sign), urine output (oliguria <25 mL/hour causes accumulation), oxygen saturation, and conscious level. Check serum magnesium about 4 hours after loading and adjust the infusion; keep 10 mL of 10% calcium gluconate at the bedside as the antidote, given IV over 10 minutes for toxicity or arrest.
Stop the infusion for absent reflexes, respiratory depression, oliguria, or confusion, and seek senior help. Watch also for pulmonary oedema from fluid overload, particularly postpartum, and be cautious with concurrent nifedipine, which potentiates hypotension and neuromuscular blockade; labetalol is the safer first agent here. Continue magnesium for 24 hours after delivery because eclampsia risk persists, and monitor platelets and LFTs daily until they recover.